Oral History Interview with Tim Schenz by Matthew Crawford

February 23, 2023
Location of Interview: Phone interview from Matthew Crawford’s Office at Kent State University in Kent, Ohio

Liquid Crystal Oral History Project
Department of History
Kent State University

Transcript produced by Sharp Copy Transcription

DR. MATTHEW CRAWFORD: My name is Matthew Crawford. I'm a Historian of Science and Associate Professor of History at Kent State University. Today is February 23rd, 2023, and I am interviewing Dr. Tim Schenz, over the phone, in my office in the Department of History at Kent State University in Kent, Ohio. Dr. Schenz, thanks for agreeing to speak with me today.

DR. TIM SCHENZ: You’re welcome.

CRAWFORD: I wanted to start off with a question about your last position. I understand that you're currently retired, but I wonder if you could tell us your last professional position and the name of the institution or employer that you worked for.

SCHENZ: I was a Research Fellow with Abbott Laboratories, what is now called the Abbott Nutrition Division of Abbott Laboratories.

CRAWFORD: Thank you. I’m sure we'll circle back to talking about your time at Abbott. How would you identify yourself as a scientist and your field of research?

SCHENZ: I would identify as a physical chemist, with probably specialties in rheology, colloid science, surface science.

CRAWFORD: Could you explain a little bit about what a physical chemist is, as opposed to other types of chemists?

SCHENZ: A physical chemist really looks at trying to find out why things happen, not just simply to describe what happens. We mix these two things together and we get this product; well, that’s one form of chemistry. But physical chemistry gets into the mathematics of chemical processes, and even physical processes. When those two join together—chemistry and physics—we end up with physical chemistry. So, a lot of use of mathematics to explain things that are going on. I think that’s a pretty good explanation.

CRAWFORD: Thank you very much. I want to start first with asking you about your early life. I wonder if you could tell us what year you were born, where you grew up, and a little bit about your early childhood.

SCHENZ: I was born in 1946. Actually I am probably one of the oldest Baby Boomers you'll ever talk to. I was born on January 2nd, 1946. [laughs] They say Baby Boomers started in 1946, so I’m one day into it. Actually, I was born in Washington D.C. My father was deployed with the U.S. Navy in Washington. But then at six months of age, which I do not remember obviously, the family moved back to the Akron, Ohio, area. That’s where I grew up—in Akron, Ohio, and later a suburb of Akron, south of Akron. At that time, it was called Manchester, Ohio. It’s now called New Franklin, I believe. What else was on the agenda for that question?

CRAWFORD: I just asked what your early childhood was like. What was it like growing up in Akron?

SCHENZ: It was good. First of all, I’m an only child, so no siblings, so I pretty much was spoiled the whole time. So, yes, growing up in Akron was good. Of course the rubber industry was there during the 1950s and 1960s, so a lot of growth in Akron, a lot of employment, so the economy was good. I was in Akron City Schools until third grade, and then in third grade moved out to the suburbs to the Manchester School District. The schools were very good in Manchester. So, yeah, I had a good childhood, I think.

CRAWFORD: I know you mentioned that your father was in the Navy when you were born. What brought your family to Akron?

SCHENZ: Both of my parents were originally from southeastern Ohio, and so during the late 1930s, early 1940s, most of the family moved to the Akron area, so a lot of the family was in Akron, and that would have been just a natural place to jump to after my dad’s Navy service.

CRAWFORD: I wonder if you could say a little bit about what professions your parents were in.

SCHENZ: My mom stayed at home until I started to go to school, and then she just had a variety of jobs, mostly retail kinds of positions, although in the end she did bookkeeping positions before she retired. My father was very handy. I mean, he could do almost anything. And so he had a lot of mechanically oriented jobs. He ended up at what is now Goodyear Aerospace, as a mechanic at Goodyear Aerospace. He was in the brake division. They made antiskid brakes for aircraft, and so they would have to service these units as they used up the brake linings. He enjoyed that quite a bit. That was his last job.

CRAWFORD: Did your parents attend college, and get any graduate degrees?

SCHENZ: No, no. They were just high school graduates. I was actually the first in my mother’s family to attend college.

CRAWFORD: What was that like? Was that important for your family, or important for you personally?

SCHENZ: It was certainly important for my parents, I believe. I don’t know how the rest of the family thought about it. I don’t really have any recollections of anything like that.

CRAWFORD: At what age did you become interested in science? Were you interested in science as a child?

SCHENZ: Yes! Yes, I was. I was. I can remember wanting the Gilbert chemistry set [laughs], or of course had an erector set, and all the things that we could build, that I could build and work on. I really enjoyed science from an early age.

CRAWFORD: Could you explain what the Gilbert chemistry set was?

SCHENZ: It was a retail set that had this case, this metal case that it came in, and it had these various chemicals in there, and then you had an instruction book of different reactions that you could do. You could never make this toy today. [laughs]

CRAWFORD: [laughs]

SCHENZ: It would just be way too dangerous for kids to get into today. It had a little alcohol burner in there that you could heat things up, little test tubes, and you made solutions and mixed them together. There were probably about 10 or 20 different chemicals, little bottles of chemicals that they had in there. Today, you could never do it. They’d say, “Oh, a kid could drink the whole thing or eat the whole thing.” We could never do that. [Laughs] That was the Gilbert chemistry set.

CRAWFORD: What do you think it was that attracted you to science as a kid?

SCHENZ: You know, I don’t know. I think it was just I liked—I don’t know what it was. I liked gadgets. I still like gadgets. My wife says just give me something with a screen or a motor, and I’m fine. But, yeah, I liked gadgets, and liked using them to do things. I just don’t know. It was just there.

CRAWFORD: Were there people in your early life that encouraged your interest in science? It sounds like your parents were getting you erector sets and this chemistry set and stuff.

SCHENZ: Yeah, right. Well, not specifically. I really can’t remember any specifics. I do know that in high school, I had a wonderful, wonderful chemistry teacher. Jumping ahead a little bit, though. This was a small high school. We had maybe 500, 600 students in total, so it was a small high school. But yet, she was offering two years of chemistry in high school. It was great. I just ate that up. That was wonderful. And really got quite sophisticated in terms of the chemistry that we studied. In its day, although they didn’t call it then, it was kind of like advanced placement chemistry, but in 1964, when I graduated, it wasn’t called that. But yeah, it was essentially advanced placement chemistry.

CRAWFORD: Do you remember the name of that teacher?

SCHENZ: Yes, her name was Carol Bartels, B-A-R-T-E-L-S. She was wonderful. She had a real big influence on me wanting to go to college and study chemistry in college. Actually she’s the one that found out about—the college I went to, Westminster College—found out that they had a good chemistry department and they were offering scholarships. So, she was instrumental in that.

CRAWFORD: You said that she offered two years of chemistry at your high school. Was that unusual at the time?

SCHENZ: Oh, yes, very unusual. I think two years of any science was unusual at that time, whether it be physics, biology. Of course mathematics, you’d start out with trigonometry and you’d go on with geometry and algebra. At that time, they didn’t even offer—one didn’t even do calculus in high school. Now, it’s common to do calculus in high school. But yes, any advanced courses in the sciences was very unusual at that time.

CRAWFORD: Is there any experiences that stand out from those courses that you took in high school, in particular?

SCHENZ: Of course, the chemistry ones, I really enjoyed, and the math ones, too. She was a big—to go on a little bit more about her, she really encouraged us to enter science fairs. I think they still do them. She would help us—and the projects that I would do—my senior year, I did a project—it wasn’t even involved with chemistry; it was more physics related—well, I guess actually it’s more thermodynamics if anything. Anyway, she located a guy in the school district who was a good machinist, and he helped me build this apparatus. The science fairs were held at Kent. I’m not sure if they're still held there or not. Anyway, my senior year, I did have my project at the science fair at Kent, and I won first prize in the science fair at Kent, which entitled me to go to the national science fair, which was held in New York City. So in I guess May or June of my senior year, I went on a bus by myself to New York City! [laughs] I looked back at this, and I said, “I can’t believe my parents just put me on a bus!” To go to New York City. Anyway, that was a great experience, just being there.

CRAWFORD: I wonder if you could describe for us—this might seem like a fairly basic question, but maybe somebody who doesn't know—what is a science fair? What is it like? Can you give us a sense?

SCHENZ: Students will put together a project of—usually the goal is, we're going to put together something that proves a point or we investigate something that people don’t know about. You try to use the scientific method to investigate properties and outcomes. The scope of the project needs to be fairly narrow. Students will put together a project, and then they'll display these projects all in one setting, one afternoon, or one morning and afternoon, usually in a big auditorium, a big arena kind of thing. Then there will be judges that come along, and they'll talk to each individual participant. They have a standard form, I think, that they use to grade. They look to see, how much does the student understand? Did they use good scientific methodology? What was the result, and how innovative was it? All kinds of things that you could judge a project on.

CRAWFORD: What was the national science fair in New York City like?

SCHENZ: Oh, there were some really fantastic projects there. I don’t think they had any prizes that they were—everyone got a really nice slide rule. [laughs] This tells you how old it is; it was 1964.

CRAWFORD: [laughs]

SCHENZ: And I still have the slide rule. It’s really nice! It was outstanding. There were just some really fantastic things going on. The thing is, though, too, I had to pack up my project so it could fit on the bus, so my dad helped me make this big case to put everything in and hope that it got there okay.

CRAWFORD: That sounds like quite an experience! You mentioned you graduated high school in 1964 and then started in the fall at Westminster College. Is that correct?

SCHENZ: That’s correct, yes.

CRAWFORD: You mentioned that your high school chemistry teacher helped you find Westminster College. Did you look at any other schools, or how did you decide to go to Westminster?

SCHENZ: I decided to go to Westminster because they were the only ones that offered me financial help. It was quite different in those days. Today, everyone fills out that form that lists the family income and all that stuff. That wasn’t done then. They were the only ones that offered me a scholarship, so the financial part of it was real important there. But I looked at Mount Union. I looked at Heidelberg. Smaller colleges. I think I felt more comfortable at smaller colleges, coming from a smaller high school. Those are the two I remember. I think I looked at the University of Miami, also, and maybe Muskingum.

CRAWFORD: Did you go to Westminster intending to major in chemistry, or did you start out in something else and then switch to chemistry?

SCHENZ: I wanted to major in chemistry. No question.

CRAWFORD: You knew that from the beginning.

SCHENZ: Yeah. And what was nice is that because of my high school background, the two years of chemistry—at the beginning of the year, all the chemistry majors, they had them take a test, and I tested out of freshman chemistry right from the get-go. So, my freshman year, I was in—the second year of chemistry was analytical chemistry. So, right away, I was a year ahead of everybody else in my class.

CRAWFORD: Was the transition from high school chemistry to college chemistry difficult, or—? It sounds like you were pretty well prepared.

SCHENZ: Yeah, I was. It wasn’t that difficult. No, I didn’t think so. I think every chemist has—anybody who studies chemistry has specialties and things that they really like, subjects they really like, subjects that aren’t their favorites. For me, organic chemistry was—oh, I hated it. [laughs] So I stayed away from organic chemistry as much as I could.

CRAWFORD: What was it you didn’t like about organic chemistry?

SCHENZ: It was a lot of memorization. To me, anyway, it struck me as just a lot of memorization of all these kinds of reactions that could happen. I think if you talk to an organic chemist, they could probably tell you, “Oh, no, there’s something behind it that helps you understand what the reaction is going to do.” But for me, I just—it didn’t sit well with me. [laughs]

CRAWFORD: I wonder if you could talk a little bit more about the science curriculum at Westminster. What was the experience of being an undergraduate in chemistry in the mid-1960s at Westminster?

SCHENZ: First of all, we had a very good faculty. Westminster was a small college; I think maybe a student body of 1,200. A small liberal arts college. But yet, the Chemistry Department there was certified by the American Chemical Society. Chemistry departments could provide and be certified by the American Chemical Society, which is kind of the main chemistry society in the United States. What this means is that the faculty meets certain standards, and the courses they offer meet certain standards, and laboratories meet certain standards. That was really important, I think. That brought the Chemistry Department up to a certain level of expertise that was important, I think, for us students. I think that helped also in terms of people who went on to get a job or go to graduate school. That was a nice thing to have on the resume, that it was certified by the American Chemical Society. Overall, it was a great experience of being in science. There are a lot of long hours involved in chemistry. I suppose if you're in English, you spend a lot of time writing things, or researching things, but in chemistry, it was a lot of lab work, a lot of time spent in the laboratory, trying to get things to work [laughs].

CRAWFORD: You had the opportunity to do lab work, it sounds like, as an undergraduate?

SCHENZ: Oh, yeah. Every course—is that true?—I think almost every course—there were a few that didn’t, but almost every course had a laboratory component to it. My first course was analytical chemistry, so then, yeah, we had analytical labs probably twice a week. As you went through the course, you would look at different ways to analyze an unknown sample, and then you had to—part of all that, you had to learn to write lab reports. So, yeah, it was good. A lot of lab work.

CRAWFORD: You mentioned part of the reason why you're spending a lot of time working in labs is you're trying to get things to work. Again, for somebody who might not know a lot about chemistry, what is it—? Because there might be a kind of popular conception of, oh, you just weigh things out, mix them together, and boom, you're done. It’s more than that. I wonder if you could talk a little bit about, what are the skills that you're trying to refine through this lab work?

SCHENZ: In a sense, chemistry is menu-driven. It’s just like a recipe. So, in a sense, yes, you need to put things together in a certain way. But there are the things underneath the recipe that are very important, and a lot of times it’s detailed. It’s how careful can you be to get the result that you need. If you're not careful, you're not going to get—for example, let’s say with organic chemistry, you want to—they tell you, “Okay, you're going to mix these three things together, and you'll get a product, and you have to purify it.” Then you weigh it out at the very end, and you see how much did you actually get. Well, if you're not careful in terms of the cleanliness of your lab equipment, how careful are you in weighing things together, how careful are you in keeping the temperature of the reaction at the right temperature—and then purifying it, filtering, and purifying, if you're not careful in making sure you get everything—the amount you get is not going to be as good as it should be. So, yeah, I think it is just a lot of detail. And that appealed to me, too. I am kind of a detail person.

CRAWFORD: It sounds like maybe there’s this element of learning good habits.

SCHENZ: Oh, yeah. We call them lab techniques. Yes, we learn a lot of good techniques for laboratory. That’s a lot of what it is.

CRAWFORD: At the risk of asking a redundant question, could you give us an example of what a good lab technique is?

SCHENZ: Let’s see. [laughs] Hmm. Well, I’m just trying to think. Let’s say you want to weigh—back in [laughs] the day, we didn’t have electronic scales, so everything was weighed out using basically what were mechanical scales or balances. You weigh something by putting weights on the other end of the scale. Those are for the larger weights. But then you can move onto what are called analytical scales. Those can weigh down to the microgram level. So, you have to be just scrupulously clean with an analytical balance. I mean, even your fingerprint can weigh a couple milligrams.

CRAWFORD: Wow.

SCHENZ: So if you're not careful—everything has to be handled with forceps. The paper that you use to weigh things onto, you have to be careful of that. So, just a lot of—that would be a good technique, of you just have to be so careful. And don’t sneeze.

CRAWFORD: [laughs]

SCHENZ: [laughs]

CRAWFORD: Yes, of course. This is a bit of a sidebar, but since you've referenced that when you were in college you were using mechanical scales, and now we have electronic scales, it seems like a good time to ask, how has the technology of chemistry labs changed? Has electronics really transformed the practice of chemistry over your career?

SCHENZ: Absolutely. Oh, just incredibly so. Especially in the areas of computers, computerization. We were very fortunate at Westminster in that my senior year, they were able to get a small IBM computer. This is not a personal computer; this is a computer that took up a room. We learned programming languages, so we could then take the data that we were generating in a chemistry lab and put it through a computer program to figure out—one way you could think about it is let’s say you had a bunch of data points. Can you generate an equation that would be the best fit for those data points? So, yeah, that’s where computers are great, much faster. You can do it manually, but it just takes forever and it was a pain in the butt. But then computers, as they were miniaturized and you went to the PCs, then scientific instruments were hooked up to computers, so the output of scientific instruments was computerized. Then that just opened up—the work involved in getting results was so, so greatly reduced.

CRAWFORD: So it really makes the collection and analysis of data much more efficient?

SCHENZ: Absolutely. Oh, yeah. You can do more—just compare things, compare different sets of data to each other and then get nice printouts. Yeah. As we get later on to my graduate work—I mean, everything was manually done.

CRAWFORD: Now, during your time at Westminster, were there any professors that had a particular influence on your undergraduate career in science?

SCHENZ: Yeah. My favorite professor was my physical chemistry professor, Dr. Percy Warrick, W-A-R-R-I-C-K. He just had a great grasp of physical chemistry, and it really clicked for me when I took his course.

CRAWFORD: Do you think taking that course with him had any influence on you deciding to pursue physical chemistry?

SCHENZ: Oh, I think so, yeah. I think up until that time, I wasn’t sure what area of chemistry I wanted to go into. Maybe analytical, because it was details, a lot of details there. But physical chemistry, then the math really started to kick in for me. So, yeah.

CRAWFORD: We've talked about some of the courses and the lab work connected to courses. You mentioned working with this IBM computer. Did you have any other experiences in science at the college level, beyond courses? Did you have a chance to do research with a faculty member or something like that?

SCHENZ: Yes, exactly. Because I was able to skip my freshman year of chemistry, my senior year I was able to do a special project with—actually it was the chairman of the department, Dewey DeWitt—D-E-W-I-T-T. He set up a special project for me to investigate the reaction of lithium with organic molecules. It was a lot of organic chemistry, which as I’ve already said, I wasn’t real crazy about, but it was a good way to learn more lab techniques. So, that was nice.

CRAWFORD: At what point in your undergraduate career do you start thinking about maybe pursuing a career in science? Was that the goal all along? When did you start thinking about graduate work?

SCHENZ: My senior year, I think that’s when everybody starts thinking, beginning your senior year, “Okay, what am I going to do next?” Obviously the paths that were open at that time were, okay, get a job in chemistry, or go on to graduate work. By that time, I had invested so much time in chemistry I really couldn't see what else I was qualified for. Then you started to look for jobs, and/or graduate school. That’s when we started, in senior year.

CRAWFORD: I believe you graduated from Westminster in—was it 1968?

SCHENZ: That’s right, 1968.

CRAWFORD: What type of job in chemistry could you get with a college degree at that time?

SCHENZ: I did look into jobs in industry, mostly. That’s where you could go with a bachelor’s degree. I was able to get a job offer from Goodyear Tire and Rubber at their research center. The job would have been a little higher than a lab technician, probably entry level above a lab technician. That was my ace in the hole if nothing else panned out. But I think I really wanted to go on to graduate school. As you may have heard when you talked to my wife, Anne, we met at Westminster the first day of my classes. Since I tested out of freshman chemistry, I was in sophomore chemistry which was analytical chemistry, and I was the only freshman, and she was the only woman in the class. But we didn’t start dating until about a year later. We were just friends. And so we started dating. She was a year ahead of me in school. She’s four months ahead of me in birthday but a year ahead in school. She graduated in 1967. She got a job teaching high school chemistry. That would have been another option, obviously, for people—to teach. But she wasn’t particularly happy with teaching high school, and I think we decided that, “Let’s give graduate school a try.” We looked at various graduate schools, and we saw a flyer from Kent State University advertising teaching assistantships, and we said, “Well, let’s give that a try.” So, we did, and they were happy to have us and gave us two teaching assistantships, and went to graduate school there.

CRAWFORD: At the time that you applied to graduate school, though, you were working as a chemist at Goodyear Tire and Rubber?

SCHENZ: No, no. This would have been my senior year. I was still in school when we were nailing all this stuff down. My wife was working. I was still going to school.

CRAWFORD: I see. One thing that Anne mentioned in my interview with her was that you had an interview with Dr. Glenn Brown at some point in the application process.

SCHENZ: I think so. She mentioned that to me after her interview, and that is so vague in my memory that I have to take her word for it! [laughs] But no, I do remember interacting with Dr. Brown, yes. No question.

CRAWFORD: You were talking about coming to Kent State, and it sounds like the offer of teaching assistantships made the school attractive. Was there anything else that attracted you to the program at Kent State?

SCHENZ: Yes, they had a very good chemistry department. There were a couple faculty members who were pretty famous. Edwin Gould was there. He had written a couple books on inorganic chemistry. Quite a few of the faculty had published books, and a lot of publishing just of research was coming out of Kent at that time. And it was almost a brand-new building at that time. It was Williams Hall. So, nice facilities, and the faculty was good. And everybody seemed nice. There were nice people there.

CRAWFORD: You entered directly into the PhD program?

SCHENZ: Yes, we did. We decided to do PhDs. The options were you could do master’s, and then do that, and then go on for your PhD, but we decided—or just directly into the PhD program and didn’t have to mess around with a thesis and writing a whole thing up. So, yeah, we decided to just go for PhD, right from the beginning.

CRAWFORD: Was your intention to specialize in physical chemistry when you came to Kent State?

SCHENZ: For me, it was, yes. I really liked physical chemistry, and the physical chemistry faculty was good there. They did have a good emphasis on surface science, which then since I joined that part of the faculty, that’s where my interests lie.

CRAWFORD: Can you explain what surface science is? What do you mean when you use that phrase?

SCHENZ: Sure. This is processes—could be reactions, could be processes—that go on at the surface or the interface between two things. For example, my research ended up to be concerned with adsorption onto activated carbon. Activated carbon is used throughout—all over now—as a filter. It sucks stuff out of either water or gases, out of air, and that is surface science. You're looking at taking molecules that you don’t want, and they get stuck, they get adsorbed onto the surface of the carbon. So, that’s a surface phenomenon. Just there are three basic states of matter—solids, liquids, and gases. When those three states interact with each other, surfaces are formed. For example, if you had a solid in a gas, you’d have little tiny particles of solids suspended in air—air could be our gas—well, that’s smoke. And so there are lots of surfaces going on there. Actually you could have two liquids together—oil and water—and you mix those together, and you get an emulsion, and a lot of surfaces are formed at the oil-water interface there. So just a lot of chemistry goes on at surfaces, in all of those situations.

CRAWFORD: Maybe you've already broached this question a little bit, but what is it about the interactions at these surfaces that makes them interesting, that makes them worth studying?

SCHENZ: A lot of physical processes, a lot of life processes, go on at surfaces. For example, the cell wall is made up of what are called phospholipids, and phospholipids form an array that is actually very similar to a liquid crystal. On one side of the array is it’s water loving, and on the other side of the array, it’s oil-loving. And so you can have an outside and an inside, so just a lot of stuff that goes on at surfaces that are involved with life processes.

CRAWFORD: I wonder if you could talk a little bit about how you came to your dissertation topic or your dissertation research topic. You mentioned you were working on adsorption related to activated carbon. How did you come to this topic?

SCHENZ: The process at that time was that we were encouraged to go around and interview all the faculty members and find out, “What are you working on? What’s involved? Would there be a place for me if I wanted to work with you?” So, we did that, and I ended up working with Dr. Milton Manes—M-A-N-E-S. He was a really funny guy. I mean, he was just—and he had come out of industry in Pittsburgh from a company that made activated carbon. So he came out of industry, but then went into teaching, and so his research interest was on activated carbon. It was just a really interesting field that he was involved in. And, in the 1960s, the environmental movement was just starting to gain steam, and a lot of interest in that. It just seemed like activated carbon was going to play a big role in purifying whatever—water, air. So, there seemed to be a lot of research areas there to try to figure out how it was that activated carbon worked. And his research—can we predict, before we even do the experiment, how things are going to be adsorbed onto a certain activated carbon? That’s basically what the research was. He had had several—I think this is very important—[laughs] what’s the success rate of the students who have gone ahead of you? Has anyone gotten a PhD from this guy? If no one has, then, well, let’s think about that for a minute. But, yeah, he had had several students that had done very nice work. Then you talk to them too, and say, “What’s he like to work with?”

CRAWFORD: Did Dr. Manes have like a lab group? What did it mean to work with him? Were you working alongside him, or working independently, and occasionally conferring? Could you just give us a sense of that?

SCHENZ: Yes, he had a lab, several labs, and a group of—oh, how many were there?—three or four of us working for him. We were all working on related topics, not the same topics but they were related. His way of working was that we would have weekly meetings, and we’d map out what needed to be done for that following week. Obviously just getting started, there was a lot of reading to do, and a lot of background that had to be done. Of course, he guided and pointed to the appropriate things that needed to be done for background before you could even start. He wasn’t involved so much in the day-to-day lab work, but if something new were being introduced, then we would go over it together.

CRAWFORD: As I’m sure you're well aware, there’s more to being a scientist than just working in a laboratory. Did your advisor or the chemistry program mentor you in the other dimensions of being a scientist as well?

SCHENZ: Oh, that’s a good question. I can think of a couple areas. To me, the goal of a PhD is not so much—well, the goal is to produce a result, the dissertation, and obviously there are the results. The subtext behind the PhD is, how do I do research? How do I investigate? How do I do literature searches, and gather all of this stuff together, and bring it together, synthesize it, into something that I can use? So I think, yeah, they had a very good scientific, chemistry library at Kent, and those people were wonderful in helping us do research and that kind of literature searching. Actually, in undergraduate school, one of our courses was Chemical Literature, and we were taught how to search the chemical literature. Nowadays you just sit down in front of a computer terminal and type in what you want. Back then, it was all on paper. It was all books, and volumes of abstracts. So you really had to know how to find out what you wanted. So, that was one way. Then I think some professors were better than others at helping you communicate what you found, your communication skills. I think that was an important step, too. Dr. Manes was very good about using English properly [laughs].

CRAWFORD: Were you encouraged to try to publish papers or give conference presentations as graduate students?

SCHENZ: Absolutely, yeah. We did. We published several papers together, and I had a couple presentations at the regional American Chemical Society meetings. So, yeah, that was always a big part of—yeah. That was almost a given that we were going to be doing that.

CRAWFORD: What about applying for grants and securing funding for research? Was that something that you were a part of as well?

SCHENZ: I wasn’t part of that. Dr. Manes kind of handled that end of it. He did have some grants from the activated carbon company that he worked for in Pittsburgh. He also had grants from I think Goodyear Tire and Rubber. He had some grants there that obviously helped with his salary and then I think probably went into some kind of pool for lab equipment and that kind of stuff.

CRAWFORD: Just thinking of the Department as a whole, would you say Dr. Manes was exceptional in being someone that came from industry, or were there other faculty that came from industry as well, or were most of them academics through and through?

SCHENZ: That’s a good question. My recollection is that most were academics, and so I think Dr. Manes was probably the exception. There may have been one or two others who came from industry. But in retrospect, thinking back on it, that was great for me in seeing that, well, there are jobs out there in industry that what I’m doing in the lab can have applications to, outside just an academic environment.

CRAWFORD: Do you think working with Dr. Manes helped you facilitate—? Because you eventually end up working in industry, of course.

SCHENZ: Yeah.

CRAWFORD: Did that help you with that transition or pursuing that path?

SCHENZ: I don’t think I ever was interested in doing an academic career. I really think I wanted to work in industry. Although I have to confess, I did have a one-semester, or one-quarter academic career [laughs] after I graduated. After I defended my thesis, I did teach freshman chemistry for a quarter, so that was my academic career. [laughs]

CRAWFORD: How come you weren’t interested in pursuing an academic career?

SCHENZ: Well, that’s a good question. I just don’t know that I wanted to. There were a lot of politics. As you know, [laughs] in an academic environment, there are just lots of the politics going on, in faculty, and I just don’t know that I wanted to put up with that. I think that was the big drawback for going academically. I think from a financial perspective, going academically was much less certain. As you mentioned, professors always need to be looking out for grants and that kind of stuff to supplement, and boy, that was just a big responsibility, I thought, that I just didn’t want to have to do. Get into an industrial lab, and go from there.

CRAWFORD: I’m curious to ask, just because of the nature of the oral history project that I’m doing, did you have any interactions with the Liquid Crystal Institute? I know that wasn’t really your area of research as a grad student.

SCHENZ: Yeah, and I was thinking about this as I was getting ready for it. We did interact with people from the Liquid Crystal Institute, and a lot of it was in terms of laboratory help. For example, in our labs—and one of Dr. Manes’s labs, we shared with an analytical professor, Robert Culp. He was great at using early models of computers—this was a PDP-8/e, I believe, was the model number. It sat on a rack. But he could gather data using that. I was using it, too, with some of my work. So, we would help other students who needed help with gathering data by computer. Or we also had ways of using early transistors, made our own little circuit boards to do temperature control, of items. Of course with liquid crystals, temperatures can be a very important variable in terms of the different kinds of liquid crystals you have. For example, for my wife’s research in liquid crystals, we helped her make a little oven that she could keep her samples in while doing experiments on them. Those are the kinds of interactions we had, I think.

CRAWFORD: I wonder if you could maybe just give us an example of, for the research for your dissertation, working on adsorption in activated carbon, could you give an example of the kind of experiment that you might do to study that process?

SCHENZ: Sure. Of course, the easiest experiment is you take a flask, you put some carbon in it, and you have a solution. For my part, they were organic liquids. But let’s say we had methanol alcohol, [wood] alcohol. Then we would put a known amount of benzene in the solution, and then we’d put that into the carbon and seal it up and just shake it for 24 hours and let the carbon absorb all the benzene that it could. At the end, you’d analyze the liquid that’s above the carbon, for benzene let’s say, and then by difference you’d know how much was adsorbed. Then you would have a whole set of flasks with different amounts of benzene in them, and so you for different loadings of benzene, you’d get different amounts adsorbed, and you’d get an adsorption curve. So when the benzene is at this concentration, this much will be adsorbed. If it’s at a lesser concentration, this much will be adsorbed. That analysis was carried out by gas chromatography, which is a great tool for doing that kind of stuff.

CRAWFORD: Again, apologies for the basic questions, but again, just thinking about someone listening to this interview, potentially who knows how far into the future, what is gas chromatography?

SCHENZ: Gas chromatography takes the properties of gases and allows one to separate gases into their component parts. It does that by—let’s say we have—typically we have a tube that’s packed with material that is of a certain nature that will hold onto—in our case, we were looking at organic molecules—it will hold on to different organic molecules at different rates. So if you have a mixture of organic molecules and you put them into this tube at one end, and there’s a flow going through the tube—and usually it’s at a high temperature so that the liquids are made into a gas—then they are absorbed at different rates along this tube, and eventually they all come out at the end of the tube. There’s a detector at the end of the tube, and so they get separated in this long tube—it’s actually a coil; it just gets coiled up—and so they come out as peaks. Okay, here comes methanol; it came through first. Oop, there’s the little peak for benzene. Oop, there’s a smaller peak for toluene. It’s in there, too. So you can separate a mixture into its component parts. And then the size of the peak tells you how much is in there.

CRAWFORD: So the gas chromatographer is producing like a roll of paper that has what would look like kind of a graph on it?

SCHENZ: Yeah. Back in the day, it was a recorder, yeah. It was a piece of paper, yeah. And recorders at that time had what were called integrators in them, that would—this was another pen that would mark out—that would allow you to calculate the area under the curve that you produced, and the area was proportional to the amount of material that was there. You could calibrate it by using a known amount of material, and then you could calculate what the unknown was.

CRAWFORD: In terms of the peaks for the different materials that are coming out, you've already determined, “This is when we expect methanol to appear”?

SCHENZ: Exactly. Now, if you had an unknown that you didn’t even know was in there, back to then in the 1980s, then they coupled gas chromatography to mass spectrometers. It was a GC-MS, a gas chromatograph mass spectrometer. Then the mass spectrometer, as the peaks would come out, could analyze the exact nature of the peak. It would give you what its molecular weight was. So that was a big step forward. But we didn’t need to do that.

CRAWFORD: You said the GC-MS machines started to come into use in the 1980s?

SCHENZ: Mmhmm, I believe so. 1970s or 1980s, yeah.

CRAWFORD: I wanted to go back—your description of the experiment that you did. I think maybe this was just a “for instance,” but was there a particular reason why you would be looking at something like benzene as opposed to some other material?

SCHENZ: For example, benzene could be a contaminant. Let’s say we didn’t want benzene in there, or any other organic compound that we wanted. Dr. Manes’s research originally started out with these organic liquids or organic solids in water. Of course everybody can understand that we want to get stuff out of water. But you may want to purify other things, too. So we went on to liquids, organic liquids, as our solvent.

CRAWFORD: Again, forgive me if this is a question of ignorance, but is benzene a good stand-in for organic contaminants?

SCHENZ: It could be. But we covered a whole range of different kinds of organic contaminants. We would do—my research; I just looked at it briefly—we had maybe a library of maybe 10 or 20 different organic things that we wanted to see how they behaved on carbon. And, if we didn’t know how they were going to adsorb, could we predict how they were going to adsorb?

CRAWFORD: Was there any alteration to the carbon that was being done in these, or were you more or less using the same activated carbon?

SCHENZ: We were using the same batch. It was a huge batch of carbon. Because yeah, you start changing the carbon; that can obviously change how much you're going to adsorb. So we wanted to keep that—that’s the one thing we wanted to keep constant. [laughs] Yeah, don’t change too many things at once. That’s another scientific principle you learn, very early on.

CRAWFORD: [laughs]

SCHENZ: Don’t change too many things at once!

CRAWFORD: Is there a particular experience from your time as a graduate student at Kent State that really stands out in your mind? A favorite memory, perhaps?

SCHENZ: One of the things we had to do with this whole research was—I’ll get a little technical here, though. If you were adsorbing a molecule that was normally solid at room temperature—let’s say it was naphthalene, which is the substance that makes up mothballs; you’d recognize the smell right away—that’s pretty straightforward because basically what naphthalene would do when it’s in solution, it would still be a solid—it could be dissolved, but it would still be always in a solid state—and it would kind of just precipitate. You could think of it as precipitating onto the carbon. That’s pretty straightforward. But with the work I was doing, these were miscible—M-I-S-C-I-B-L-E—liquids that dissolved in one another. They were liquids at room temperature. And so, they wouldn't precipitate out; they would—benzene, for example, would go onto the carbon but there would be a gradient of benzene from the very closest surface of the carbon out away from the carbon. And so, the problem was, how do you calculate what that gradient looks like. I mean, obviously experimentally we knew what it was. We could say, “Okay, this much is absorbed.” The upshot though is that you can’t get all of the benzene out. There’s still going to be a finite amount left in solution. You could run it through multiple, multiple columns and get down to a certain level, but ultimately you can never get all of it out. But, we came up with—using a lot of thermodynamics and equations and stuff—an equation that we thought would predict what that gradient looked like. And the problem was, the equation we came up with was a transcendental equation. I don’t know if you're familiar with that term.

CRAWFORD: No.

SCHENZ: [laughs] Basically, instead of saying, “Okay, the amount absorbed on this side equals the amount that’s in solution on that side”—well, that’s just a straightforward equation. A transcendental equation cannot be solved for a single variable. So the amount that’s absorbed is on both sides of the equal sign, and you can’t solve the equation—no matter what algebraic manipulations you use, you can’t get that equation into a term of the amount absorbed equals this, this, and this; a function of this, this, and this. So what I had to do was create—and this is where I was really thankful for the experience I had at Westminster College—I created a computer program that would, by iteration, solve these equations. “By iteration” means, okay, you know that if you put a value in on this side, on one side of the equation, and you put the value in on the other side of the equation, you know if one side is greater than the other. Then if you go, “Okay, let’s increase it by a factor of two,” and—"Okay, it’s still greater, let’s increase it by a factor of three”; “Okay, one side is—oop, it’s switched; it’s now less-than.” So the true solution lies between two points, and now we can go back by iteration and decrease our increments until we can hone in on the final value, at least have enough confidence to two or three decimal places that it would print out that value. So, that’s a way to solve transcendental equations. It’s a brute force approach that you start out with big numbers and then you put smaller numbers in, until you hone into the point where, okay, it’s switching between these two values, so you know that’s where it is. So, I created this computer program and then I got—of course Kent State at that time had a computer center, and so every night, I would take my computer cards over to the computer center, they’d run during the night, and the next morning I’d go pick them up and get the printouts and see what we had. That was very satisfying, to create this program and see that it actually worked, and that we were able to predict the results that we got.

CRAWFORD: The final value that comes out of these transcendental equations that are being solved by this computer program, what does that tell you? What does it mean? What does it represent?

SCHENZ: It would be the amount that was absorbed. That’s what we were looking for—the amount that was absorbed, given these other variables that we had in there. We were looking—just as we did the experiment with the series of flasks with different amounts of benzene, we were looking for, “Okay, if we had this amount of benzene to begin with, how much would we predict is being adsorbed?” So we were generating a curve based on it and compared it to our experimental data.

CRAWFORD: Was the goal of these experiments really to produce this predictive equation?

SCHENZ: That was one of the goals of the research, yeah. "Can we predict what is going to be absorbed?” Because then you don’t have to do the experiment! Right? If you can predict it, you don’t have to do the experiment. All you need is some basic fundamental properties of the materials you're starting out with. And it turns out our fundamental properties were, strangely enough, the refractive index of the liquids. The only other piece of information we really needed was, how does the particular compound or molecule we're working with behave when it absorbs onto activated carbon from the gas phase? So I did a lot of gas phase absorption. Again, once you do one curve of that, what that does is characterizes the carbon. How does the carbon behave to this molecule? Once you get one molecule, you can pretty much generate all the other molecules from one. So it’s a shortcut to predicting absorption.

CRAWFORD: Was part of what you were doing, too, looking at different fundamental properties and seeing which ones would be useful in terms of making this prediction about absorption?

SCHENZ: Part of it was, yeah. A lot of the work that had gone on ahead of me kind of honed in on some of these basic properties, but the gas phase part was more unique.

CRAWFORD: Why was it important to have such a predictive equation? Again, kind of a basic question, but why not just do the experiments? Why do you want to have this equation?

SCHENZ: The reason activated carbon works is that it’s basically coke. It’s wood that has been turned into coke, which means it has been burned up in an oxygen-free atmosphere or very limited oxygen. So what you get are these little, tiny pores and cracks and fissures in the carbon. Sometimes, it can be activated by hitting it with water vapor, steam, and that makes even more fractures. Well, this whole process of making activated carbon can be—there are a lot of variables that there you could play with, to try to get the best kind of carbon, particular kind of molecule that you want to adsorb onto there. So, it would be a way to evaluate carbons, really.

CRAWFORD: I see.

SCHENZ: What can we do to the carbon to make it better? Did we have any effect? Did it make it better? And, are there compounds that are better absorbed on this carbon than on other carbons? That kind of thing.

CRAWFORD: You mentioned the rise of the environmental movement and things like that. Basically, if you were looking to have a carbon that was activated in a particular kind of way, if I’m saying that right, for a particular kind of application, these sorts of equations would allow you to predict its utility without actually having to—

SCHENZ: —do much experimentation. You’d have to do a little bit, but yeah, exactly right.

CRAWFORD: Which would make sense, because then you can save the activated carbon for like actually cleaning up an oil spill or something like that.

SCHENZ: [laughs] And save time. You don’t have to mess around with doing all the experiments. Because as later learned in my career, time is money, in industry.

CRAWFORD: What year did you finish your PhD at Kent State?

SCHENZ: I defended my dissertation in June, July, or August of 1973, I think.

CRAWFORD: What happens after you graduate with your PhD in physical chemistry?
SCHENZ: Then, you try to find a job. At least for me, I tried to find a job. For my wife and I, it was unique; we were both getting our PhDs in physical chemistry. We had decided that I would most likely be finishing first, so I would get my dissertation together and she would do the rough typing of it for the oral defense. Then we’d just switch jobs. Once I had gotten mine, she had finished hers, and I typed up her rough thing. But in the meantime, I was looking for jobs probably, oh, three or four months even before I knew that we would be finishing up the defense. And I believe—I think we kept count—it was a very rough time for industry hiring PhD graduates, at that time, at the end of 1973. I believe I sent out about 150 resumes.

CRAWFORD: Wow.

SCHENZ: This was not by email, right? No email. You had to make a copy, a physical copy, a Xerox copy, of your resume, type a letter to go on top. Of course, you kind of had the language all worked out anyway. Then put it in the mail. It went out. Maybe three, four, five weeks later, you got a reply. I sent out about 150 resumes and letters, and I got one job interview—

CRAWFORD: Wow.

SCHENZ: —out of all of that.

CRAWFORD: Wow. [laughs]

SCHENZ: Yeah. I would get letters back with my resume returned. I mean, that was kind of disheartening! [laughs]

CRAWFORD: Yeah, geez! [laughs]

SCHENZ: Anyway, the one job interview I had was at General Foods Corporation in Tarrytown, New York. Went out for the interview, flew out—they paid for me to fly out—had the interview, and about a week later, they called and said, “We’d love to have you join us.” That was in I think October of 1973, and I think I started in January of 1974 at General Foods Corporation.

CRAWFORD: You said it was a rough time to be looking for a job in industry as having a PhD in chemistry. I think that's obvious from your experience of sending out so many resumes. What was going on at that time that—?

SCHENZ: That’s a good question. I just think there was a general downturn in research in industry. I’ve thought about that: Why was it so hard? I just really don’t have a good sense of why it was hard. I know academic positions were tight, also, at that time, too. I really don’t have a good answer for that.

CRAWFORD: When you started at General Foods, what’s the position that you're doing?

SCHENZ: I started out as a—I think it was called a senior chemist. Yeah, that was it. They actually had a physical chemistry group in the research center at General Foods. General Foods at that time had a lot of different brands going on—Maxwell House, Jell-O, Tang. Just as lot of different household names [laughs] in terms of food products. Really what I did was transition from purely surface science research in graduate school—I really transferred to more of a food chemistry role with an emphasis in surface phenomenon at General Foods. But it was a physical chemistry group, at General Foods, and had some wonderful people working there, and some really good times, there.

CRAWFORD: You said you were working at a research center for General Foods?

SCHENZ: It was a General Foods technical center, and it was as big as, maybe bigger than, the Chemistry Department at Kent State. It was a big research center. This is where all the product development would go on. There was actually basic research going on. It was a big effort at that time.

CRAWFORD: Your work at that time, was it more on the basic side, or more on the applied side?

SCHENZ: It was both. We’d do both. We’d do some basic research and then we would also support product development. For example, one of the products that General Foods made was Cool Whip, and still make it. Or Kraft; I don’t know who makes it now. They've sold so much of it. It’s now owned by Kraft Foods and they've sold off a lot of stuff. But anyway, whoever makes Cool Whip. Cool Whip is interesting, because it’s an emulsion. It’s fat and water, oil and water, but it’s also a foam. So it’s air—a gas—in a liquid emulsion. So there are three interfaces going on here, or two interfaces going on. It’s not just oil and water; it’s air, and oil, and water. So, a lot of surface things going on there. We did a lot of work on research on Cool Whip. Are there other ways to make it more efficiently? The main protein that was used in Cool Whip is sodium caseinate, which is a major component of milk protein. It’s a milk protein, but they can isolate that out, and you don’t have to use milk; they use the protein instead. There are all these different kinds of ways you can make sodium caseinate. So, how do you evaluate those for effectiveness, without having to make a bunch of batches?

CRAWFORD: You've moved from the academic environment of your PhD now into an industrial science environment. What was that transition like? Was it difficult?

SCHENZ: It took a while, but basically, the one thing I learned that really helped me was—and I think I got this from Dr. Manes and his background in industry—what is the one experiment I can do that will show me the best results? I think there’s a real skill in terms of, how do I know what experiment to do? You just can’t go start doing other little things if they don’t really lead you toward the end that you want to—I mean, it may be very interesting, which in an academic setting would probably be okay. But [laughs] in an industrial setting, you want to get results as fast as you can. So, what’s the right question? What is the right question, and what experiment will answer that question? I think that’s the big thing I learned at General Foods in terms of having a successful career.

CRAWFORD: Part of what you were doing, then, was that General Foods or some group within the company would come to you with a certain problem that they had, and you had to design an experiment to address that issue? Is that more or less correct?

SCHENZ: Yeah. Of course, we would have an array of equipment that we used, that we could go ahead and—it might be very, very handy to use. One of the areas I got into at General Foods that really I learned a lot about and had a lot of expertise in was thermal analysis. Thermal analysis is, how do materials behave under different temperatures, at different temperatures? For example, Cool Whip obviously is distributed frozen, and as you thaw it, it melts. Well, thermal analysis, you can find out how much heat is required to melt any given substance. But it also goes much further than that, too. Thermal analysis can be used—you can weigh things as they're being heated. Do things lose weight as they're heated? There’s an area of thermal analysis called thermomechanical analysis. This looks at the mechanical properties of materials as they are heated. This actually turns out to be very important in frozen foods. One of the food areas that General Foods had was Birds Eye, all the frozen foods there. Well, frozen foods—I don’t know if you've ever had—let’s take ice cream, for example. If you take ice cream out of the freezer, and it’s a zero-degree freezer, it is as hard as a rock. But then you let it get up to about 20 degrees F, and it’s spoonable. What that means—what we can find out by thermal analysis is that part of the—the ice is still there; it’s just that there’s a very concentrated liquid, let’s say, that at zero degrees it’s as hard as a rock, and that concentrated liquid as it starts to warm up starts to soften, and flow, and it goes to what’s called a glass transition temperature. Glass transition temperatures are very, very important in food systems, and they can be addressed with thermal analysis. A good example of a glass transition—have you ever had hard candy?

CRAWFORD: Yeah.

SCHENZ: Lemon balls, or lemon drops, anything like that. You ever had lemon drops sit in your car, in a hot day? What happens is it gets really hot. That glass—it’s a glassy liquid—is really hard. But then if it heats up, it goes through its glass transition temperature and basically flows, and spreads out, and just—bleh! That same thing happens in frozen systems, too.

CRAWFORD: You said glass transition temperatures or the glass transition phase is really important to food science.

SCHENZ: Yeah.

CRAWFORD: Why is that? Just understanding like how cold you need to keep things for—?

SCHENZ: And are there ingredients—? For example, could you add ingredients to an ice cream that would make it spoonable at zero degrees F? And it turns out there are. So, yeah. Can you make a soft-serve ice cream that you could take right out of the freezer?

CRAWFORD: Right. [laughs] That would be nice! [laughs]

SCHENZ: Yeah, yeah, yeah.

CRAWFORD: I know you worked at General Foods for a little over a decade.

SCHENZ: Right.

CRAWFORD: You held several different positions during your time there. As you moved into these different positions, did your duties and responsibilities change in any significant way, or were you more or less doing the same kind of work?

SCHENZ: The same kind of work, although the areas of expertise kind of shifted and changed and went around. As I progressed through different levels, I would get more people reporting to me, so I’d have three or four people—so I would have people to direct and give assignments to, and we’d look at data together, and see how things were going. Basically it’s just all experimental stuff. I didn’t want to have too much managerial responsibility. I just didn’t like all that stuff. It was being in the lab and doing the work, doing the lab work.

CRAWFORD: What would you say was one of your most significant achievements or projects at General Foods?

SCHENZ: One that people really like to hear about—General Foods made a product called Pop Rocks. Have you ever heard of Pop Rocks?

CRAWFORD: Yeah!

SCHENZ: Pop Rocks, it’s a hard candy that has been carbonated. There are two levels of carbonation in Pop Rocks. There are big bubbles of carbon dioxide in there, but then, the way Pop Rocks are made is—you make any hard candy this way—you take sugar and water, and some invert sugar or corn syrup, whatever you use, and you boil it, and you thicken it up, and it gets to the hard crack stage. Then, when you cool it, it makes hard candy.

CRAWFORD: Right, okay.

SCHENZ: Well, you make Pop Rocks by taking this hot sugar solution at the hard crack stage and putting it into this huge tube, steel tube, which is heated. It’s about 12 inches across, about 20 feet tall, and it has a bunch of impellers on the inside. You pour it in there, and then you seal off the ends, and you start pressurizing it with carbon dioxide and you start stirring it, while it’s still hot. You keep stirring, stirring, stirring, stirring, stirring, stirring, stirring, stirring, until you get all the carbon dioxide. And carbon dioxide will actually dissolve into the liquid, the molten sugar. It’ll dissolve in there. So then you lift the impellers up so they don’t get stuck in the hard candy when it cools, and you let the whole thing cool down. And then, the whole thing cools down really—it’s all still under pressure, really high pressure. Then there’s a release valve at the bottom. You pull that—I don’t do it, but [laughs]—somehow the bottom comes off, and everything just comes shooting out the end, and this is Pop Rocks. Then you grind it, and sieve it, and get it into the right sizes. Well, and then when you pop it in your mouth, there are two kinds of sensory experiences that you have. One is that you have these pops, and that’s the big bubbles cracking. The fracture lines go through the hard candy through these big bubbles, and they break into pieces. That’s one experience. But then the next one is, you get this sizzle, in the background. And that is the carbon dioxide that has been dissolved into the candy, that when it’s being dissolved by water—your saliva—you get this sizzle. So, the plant needed—they would make these batches, and they would then do a sensory test on it. They’d send it to the sensory lab, and they’d taste it and evaluate it. Well, people were just getting burnt out tasting batch after batch after batch of—not to mention they found that their dental bills were going up quite a bit.

CRAWFORD: [laughs]

SCHENZ: So, we had been doing some work on acoustic properties of foods—crunchiness in potato chips, and pretzels. What are things that give us those experiences? So I came up with a way to evaluate Pop Rocks using acoustic meters. We had a sound analyzer. We basically took a hydrophone, go under water, stick it in a thing of water, a little beaker of water, pour some Pop Rocks on it, and immediately you would get this huge boom. All the pops would go off. And we could measure the height of that. Okay, how many decibels did we get out of that baby? Well, that correlated very well with “pop,” when you first put it in your mouth. Then, a minute later, things would settle down and there would be this background sizzle. That correlated very well with the sizzle that the humans were getting. So [laughs] we had an Israeli company build us a couple pieces of instruments that would measure these two things—the initial sound volume, and the volume a minute later. We installed it in the plants. So, yeah, we evaluated Pop Rocks.

CRAWFORD: Using these instruments that you had had developed.

SCHENZ: Yeah, using instruments, and there was a scientific basis behind it.

CRAWFORD: [laughs] Great! I know you stayed at General Foods until 1987 and then you move at that time to the Ross Products Division at Abbott Laboratories.

SCHENZ: Yes.

CRAWFORD: I wonder if you could talk a little bit about that transition.

SCHENZ: Yeah. Toward the end of 1987, there was a lot of—there were going to be major—well, there had been major cutbacks even earlier at General Foods probably earlier in 1986 and 1987. It came about that toward the end of 1987, there were going to be even more cutbacks. At that time, when people were let go, they were given—it was a very generous—they would give them one month of severance pay for every year of service, so it was a really very generous severance pay. Well, Anne and I knew that our jobs were okay, that we weren’t going to be cut at that time. However, my boss at General Foods in the mid 1980s had taken a job at Ross Products Division of Abbott Labs in Columbus, Ohio. Back in like June or July of 1987 he gave me a call and said, “Hey, I have two positions open here for you guys. Are you interested?” At that time, we said, “Well, I don’t think so. Maybe not. Give us some time to think about it.” In the time we were starting to think about it, a week or two after that, then we started to hear about all these cutbacks. We thought, “Well, you know, maybe we’d better check this out.” We came out to Columbus, they offered us two jobs, and—of the main factors behind the move was—well, it was more money. We’d get a severance package. Because we could volunteer to be let go. And, both of our families were much closer than we were in New York City. So, those were the major reasons we came here. So, yeah, we volunteered to be let go and actually saved two people’s jobs by doing that, but got severance pay for it. And, as it turned out, it was really a good move, because maybe four or five years later, they shut down the technical center there in Tarrytown and moved it to Illinois, near Chicago.

CRAWFORD: What kind of work were you doing at the Ross Products Division? What kind of company was it?

SCHENZ: Ross Products made nutritional products. Their main products were, and still are, Ensure for adults, which is complete nutrition, and infant formula, which we've all heard about in the news lately, both liquid and powder infant formula. They make Similac, Isomil, and then make a lot of specialty infant formulas for infants with digestive problems or allergies. They make those kinds of things. Then they also make a lot of nutritional products for disease-specific things. There’s a product called Glucerna for diabetics. There are a whole host of other kinds of disease-specific products that they made.

CRAWFORD: What were you working on there? Were you still doing experimental work in the kinds of work that you were doing?

SCHENZ: Yep. I actually started a physical chemistry group there, at Ross Products. So, started a physical chemistry group. Had about three or four—at the end, had five or six people reporting to me. But continued on a lot of my thermal analysis work that I had been doing at General Foods. Shifted a little bit more into emulsions, because a lot of Ross products were emulsions—fat and water—so we needed to stabilize those things. A lot of my research then was looking at the physical stability of these products. For example, Ensure. It has everything you need. You can live on this stuff. It has fats. It has proteins. It has trace minerals. While it has all these things, if you let it sit on the shelf, which they have to do—you make it, and it should be on the shelf for at least—probably be on the shelf, could be on the shelf for a year—the fat tends to go to the top, just like cream in milk, and the minerals—the calcium, the magnesium, whatever else is in there—tends to fall out to the bottom. We were looking at, are there ways to stabilize these products so that even if they did separate a little bit, they'd be easily put back in? You could shake it and they’d go right back in. So, I moved a lot into rheology—R-H-E-O-L-O-G-Y, rheology. Rheology is the study of flow. We get the term diarrhea from the Greek word “rheo.” It’s the study of flow. How do materials behave under flow? There is specialized equipment called rheometers that will allow you to look at the viscosity, the thickness, of things, under different conditions. Now, most liquids that we are familiar with have a constant velocity no matter what you do. For example, water is the same viscosity no matter what you do. However, you can get into liquids that have a different viscosity depending upon the stress or the flow that it’s experiencing. For example, paint. Latex paint. You can stir it up. It’s a liquid, right? You stir it up and it will drip all over the place. You paint it on the wall, and it stays there. It doesn't drip on the wall. Unless you get it really thick, obviously. But the reason it stays on the wall is because once it’s on the wall in a thin layer, it’s then subject to the force of gravity down. That’s a very low force, and latex paint has special additives that make it much thicker under low-flow conditions. So it thickens up on the wall, but it can be stirred up again in the pan. Ketchup is another good example. How do you get ketchup out of a bottle? You pound it at the end. Well, you've got to get all this force to get it to flow. Once it starts flowing, it continues to flow. But then once it sets up, it doesn't want to flow again. So, materials can have different flow properties, different viscosities, depending on the stress or the flow that you put them under. There are food ingredients called hydrocolloids, which are gums. Carrageenan is an example; guar gum. They can provide these different kinds of viscosities at low flows. Like the flow that a particle will experience under the influence of gravity, we can make it appear very thick, but yet it can be poured and drunk, no problem.

CRAWFORD: It sounds like flow and viscosity are two different things.

SCHENZ: Yeah. Viscosity is a scientific measurement. That’s a property that we measure. Flow can happen at any viscosity.

CRAWFORD: You were looking at these flow properties for the purposes of thinking about how to prevent something like Ensure from separating too much?

SCHENZ: Exactly. Stabilizing our products, yeah. How can we use the flow properties, the viscosity curve, at different points along that curve, to increase the stability? Exactly right.

CRAWFORD: Could you maybe give us an example of an experiment that you would have done to study these properties or think about how to improve the stability of a product?

SCHENZ: A lot of it would involve—we’d have to evaluate on the rheometer, what does the flow curve look like? At low flow, at low speeds, is it a pretty high viscosity? And at higher speeds, does it thin out quite a bit? That’s the kind of curve you’d be looking for. Then we’d evaluate materials—these different kinds of carrageenans, or different kinds of gums. And at what concentrations do we need to do and to use, to get that kind of behavior. Then we’d make up sample product and put some calcium in it and shake it up real good and let it sit and see what it looks like. Does it settle out?

CRAWFORD: I know that in 1996, you won the Outstanding Research Award from Abbott Laboratories. I wonder if you could tell us about receiving that.

SCHENZ: That was another research project that I had. This got back to the thermal analysis work that we were doing. In any event, we were using—it’s called nuclear magnetic resonance. It’s the basis of an MRI. They don’t use the term “nuclear magnetic—” because that gives people all kinds of crazy ideas. But we were using nuclear magnetic resonance to study the properties of water in our products. We could find out how water was being—for lack of a better term—sequestered or made to be less mobile, in a product, and that seemed to be good for stability. It was serendipitous, a real example of serendipity, that some of our samples—and we were using products with proteins and sugar and stuff in them—some of our samples were—I don’t know what the right word is, but they got spoiled. They spoiled. We could see that they were starting to—bugs were starting to grow in these things. When we looked at the data from the magnetic resonance, we could see that we could see the spoilage starting much earlier than we could visually see it.

CRAWFORD: Hmm!

SCHENZ: At that same time, Ross was moving towards what’s called aseptic processing of liquids. Normally, up until that time, liquid products were processed with what is called terminal sterilization. You would put the product in a can, just like the canned goods, and you’d run it through this sterilizer—high, really hot temperatures; 230, 240 degrees Fahrenheit, way above the boiling point of water—but because it was in a can, it wouldn't blow up. Everything would be killed, all the organisms would be killed, it would come out the other end, and be great. Well, the problem is that a lot of changes happen at those high temperatures in terms of taste and texture.
Ross was looking at what is called aseptic processing, and that involves taking a plastic bottle—and a lot of aseptic packaging is done today—but you have this special equipment where you bring a sterilized product, which is taken through what’s called a short-time, high-temperature reactor, so it just spends a little time at high temperature, enough to kill the bugs in it, and you bring it into a zone in the equipment that’s totally antiseptic. It’s totally germ-free. You bring the packaging in, the plastic package in, at the same time, and you sterilize it by whatever means they do. They can rinse it or do something. You bring the two together, you seal it up, and you spit it out the other end, and there’s no other sterilization that’s needed. Well, this was all brand new to Ross, and this is a company who had been doing terminal sterilization for 20, 30 years, and they were just not comfortable using this. They put out product for, one, infants; for adults who may be compromised immunologically. These are people that would depend on your product for life, and if it’s going to be spoiled, they don’t want it out there.
The question was, is there a way we can test this product before we sell it to see if it is spoiled? So, enter nuclear magnetic resonance, or, in our case, we switched over to MRI, magnetic resonance imaging. We could take product—we developed this whole elaborate system to—we make product, it goes into cases, 24 bottles in a case. We can run it through an MRI, and it’s a true MRI. Of course, everything has to be plastic. But we could image—we can take slices of this case, and we can tell if any of those bottles in the case have been spoiled. Now, it sits on the shelf for a couple weeks, and then we put it through this machine, and then once it goes out the other end, it goes on to shipping and it’s out the door. So it really gave them confidence that the process that they were working on, that they were using, was in fact pretty good. So, that’s what I got the award for, was developing this technology. I didn’t develop all the detail of the MRI; we had people that were working with us on that. But the basic research was to use magnetic resonance to detect spoilage in product. And as far as I could determine, it was the first use of an MRI in an industrial setting, in the world.

CRAWFORD: Wow!

SCHENZ: I think we had two units installed, one in Columbus and one in Alta Vista, Virginia, was another plant that we had it.

CRAWFORD: I’m just curious, was there any reaction to using an MRI in an industrial setting? Were people resistant?

SCHENZ: Yeah, we presented some papers and got some patents on it. But no, it was pretty low-key. Nobody really—

CRAWFORD: [laughs] I know we're getting close to 2:00, so I don’t want to take up too much more of your time. I think we've heard some really great stories about your experiences at General Foods and Abbott. I wanted to ask you—I know you took early retirement in 2002 to go work for an organization called Frontiers.

SCHENZ: Right.

CRAWFORD: I wonder if you’d like to talk about that for a little bit, and then maybe a couple of concluding questions, and we can finish up.

SCHENZ: Sure. My wife and I had always wanted to serve the Christian community in ways other than just through the local church, and we had always wanted to do something with the missions organizations that send the Good News out to others. So, we decided, “Well, let’s think about early retirement and spend some years doing something with that.” We had some restraints, though. My parents were living locally, here in Columbus, and they were both elderly. Since I’m the only, I had responsibility for that, so we had to really stay pretty close to home. We just couldn't go overseas somewhere and work on stuff. Frontiers was gracious enough to find some work for us to do. One of my responsibilities, or things we did a lot of, at Ross, was—as I mentioned before, a lot of computerization of equipment was starting to come in the 1980s and 1990s. And so, what we did in our lab was to—this was just when the internet was starting to come in, and we had a company intranet. We could take our lab results and—a client would come in and want some analyses, and we would do it. Well, instead of just putting the paper in the interoffice mail, we would construct a website for our lab and post the results on our website so that the client could see the results. So, I gained a lot of experience in developing websites and doing that kind of stuff. What I did for Frontiers was to help them develop an intranet of their own. On last count, they have well over 1,000 workers all over the world. So we developed—and this was a team of us—that developed 50 or 60 websites for individual teams that are out there, for individual groups, to use in their work. They can exchange documents. They can have chats with each other. I started that in 2002, and just last year, July of last year, I said, “Okay, 20 years is enough of that.”

CRAWFORD: [laughs]

SCHENZ: It was a good project, and we did a lot of good work in developing these websites, this intranet for Frontiers workers.

CRAWFORD: I wanted to ask a couple of broader questions. Thinking of the career that you had in chemistry going all the way back to high school in the 1960s until your retirement in the early 2000s, what do you see as the most significant developments in chemistry, or if you want to talk about particularly food chemistry? Are there any things that stand out, just kind of the field or the discipline, that were transformative?

SCHENZ: That’s an interesting question. From my point of view, I think in that time period there was a growing awareness, in food chemistry anyway, of looking at food systems as physical systems, not just chemistry. So, that the physical properties of food systems could affect not only the appearance, but could affect texture, could affect stability, could affect shelf life. I think there was just a growing awareness that physical chemistry really did have a role in food systems, and how they were finally developed, or the final products that were—I just read an interesting article about a [laughs]—this is funny—some group has developed a spoon that has sweeteners bonded to the surface of the spoon.

CRAWFORD: Hmm!

SCHENZ: So [laughs] when you eat something off the spoon, it tastes sweet. They don’t dissolve; they're always on the spoon. I thought, “Wow! That’s pretty cool!” [laughs] Anyway, that’s just an aside.

CRAWFORD: I should have asked this earlier, but I wonder if you could explain what you mean by the term “food system.” What does that refer to?

SCHENZ: A food system—a “food” is made up of all these different chemicals. People say, “I don’t like any chemicals in my food.” Well, news flash: that’s all it’s made of, is chemicals. So, a food system is—let’s take, for example, pudding. Pudding, if it’s made of milk, milk has fat in it. Milk has proteins in it. Milk has sugar in it. There’s that. Then the part that makes the pudding a pudding is a starch, which is a carbohydrate, a long-chain carbohydrate, that dissolves when you heat it up, dissolves in the water and gets all loosey-goosey in the thing. But then when it cools down, all the strands start to get caught up in each other and they form this gel. So, a lot of things go on in just a simple food. Then there’s flavors and stuff that go in there, too. All these things can interact with each other. That’s a food system, is what are the components, the individual components, of a food, and how do they interact with each other. They may not interact, but they very well may.

CRAWFORD: Great. So the term “food system” for you and people in your field really refers to the materials that food is composed of and how they interact or don’t interact?

SCHENZ: Yeah, and how they behave in storage, how they behave when you eat them, even how do they behave in the gut. Some of our things that we were working on at Ross was that things would get more viscous when you ate them. They’d thicken up in the gut. What that did was slow down the absorption of carbohydrates, which was great for diabetics. So, there’s just all kinds of stuff that can go on. It’s a lot more complicated than people really think. We take food for granted—

CRAWFORD: Yeah, for sure.

SCHENZ: —and what it can do.

CRAWFORD: [laughs] Just a final question. Thinking about, say, an undergraduate today who is maybe majoring in chemistry and seeking to pursue a career in science, what advice would you give to that person?

SCHENZ: I would say, find out what it is you love. What area of science really piques your interest? What is it that makes you want to keep doing that? Is it all the little molecules? Do you like to do all those little molecules? Well, maybe you’re an organic chemist. Do you really like mathematics? Well, maybe you're a physicist or a physical chemist. What is it that really sings to you? You need to find out what it is that makes you happy, in science.

CRAWFORD: Great. Dr. Schenz, I want to thank you again for your time, for agreeing to do this interview, and for sharing your story.

SCHENZ: You're welcome.

[End]