Episode 64: Dr. David Julian McClements on Food Science

Introduction to Episode

0:00Hi, you're listening to Let's Talk Chemistry, a podcast by Chemtalk. On today's episode, we interview Dr. David Julian McClements, Distinguished Professor at the Department of Food Science at the University of Massachusetts. Dr. McClements talks about the science behind next-generation plant-based foods, all the way from reverse engineering to nanotechnology and gene editing. We hope you enjoy! Hey, and welcome back to another episode of Let's Talk Chemistry.

0:32My name is Elizabeth, and I'm one of your co-hosts. And I'm Porby. Today, we're going to be talking all about food science, from nanoparticles that improve nutrients' bioavailability to reverse engineering foods. And joining us today is the incredible Dr. David Julian McClements, Distinguished Professor in the Department of Food Science at the University of Massachusetts.

Dr McClements Background

0:54Let's welcome Dr. McClements and hear more about his background and how he got interested in food science. Yeah, my name is David Julian McClements. I studied as a food scientist at the University of Leeds in England, and then I did a PhD at the same university, and then I went to the University of California in Davis to do a postdoc, and then I went to Ireland for a year to do a postdoc, and then I got a job in the University of Massachusetts in food science. I didn't know what I wanted to do when I was in the equivalent of high school, but I was really excited about science.

1:25My uncle was the only person who went to a polytechnic in England, and he did some sort of food technology course. So I thought, you know, I wanted to do something really practical with my science. So I love physics and maths and chemistry, and food science had all of those things in it, and it was a practical application that affects everybody's life. You know, it affects your pleasure, you know, like the kind of food you eat, but it also affects your health and, you know, the sustainability of the planet, and cultural things as well. So I think there's a lot of, it's really nice to see your science applied to a really important problem.

1:56I completely agree. Food is such an integral part of daily life and affects people in numerous different ways. Plus, it's one of the main things that everyone has in common. It's great to hear him talk about tackling such an important subject. Absolutely. I also love how he mentioned how food affects the sustainability of the planet, because food is such a common part of life. Some of us may not think about how the food we eat affects the planet as a whole. Unfortunately, food production is a major contributor to global climate change, especially the meat industry and animal-based foods as a whole.

2:29Millions of acres of forest around the world have been replaced with cattle pastures, and the animals themselves produce CH4, also known as mesin, an extremely harmful greenhouse gas. That's one of the reasons why plant-based foods have risen in popularity recently. They generally use less water, energy, and land to produce, and are much better for the environment. Dr. McClemmons' research is nothing short of extraordinary. He focuses on the science behind next-generation plant-based foods, looking to create more sustainable and healthy alternatives

3:01to traditional animal products like eggs. Dr. McClemmons shared some insights into the challenges of creating plant-based foods that truly mimic the real thing.

Plant-Based Foods Science

3:10Let's listen to him break down the science behind it. Yeah, I've got a number of areas. I think most of my research now is focusing on the science behind next-generation plant-based foods, so trying to create more sustainable and healthy plant-based meat or seafood or eggs or dairy products. So there's a lot of chemistry behind that. You have to understand how proteins and lipids and polysaccharides interact with each other, and you have to control the structural architecture of these foods

3:41in order to make them look and feel and smell like meat products, which is very, very challenging. It's incredible to see how technology can make such a big difference in nutrition. Dr. McClemmons uses reverse engineering techniques to replicate meat's smell, taste, texture, and even light absorption. It's like taking food apart at the molecular level and rebuilding it with plant-based ingredients. How innovative. He even challenges his students with creative questions like whether you could make meat-based fruit.

4:12Here's more from him on using reverse engineering in food replication. I think there's a lot of companies like Impossible Foods and Beyond Meat have been real pioneers in this area where they've used real sort of science to try and do reverse engineering. So you take like a beef burger, and then you have to say, you have to think like, you know, what does it look like? And that depends on the way light waves are scattered and absorbed by it. You know, what does it smell like? And that depends by the chemistry of the volatile molecules that are produced during cooking and how they get to the nose. And then you have to think of what do they taste like and how do they behave in your mouth.

4:45And that depends on the textural attributes. So you don't want it to break down too much, too quickly. It'll be mushy. So you want to have like the same chewiness. But if you look at meat products, they're very complicated from a sort of structural architecture point of view. They've got all these fibers that are interlocking with each other. Whereas you look at plant proteins, they're all like little tiny spheres like golf balls. So we have to again use nanotechnology to make great fiber structures from these plant proteins. I think I've been probably like the last 10 or 15 years, I've been focused on sort of natural food ingredients. So trying to replace synthetic ingredients in food with natural alternatives like proteins

5:19and polysaccharides and phospholipids and things. But I think probably the last five years that we've really focused on plant-based, again, mainly for sustainability issues. Another area of Dr. McClemon's work focuses on nanotechnology, used to enhance the nutritional profile of plant-based foods. Dr. McClemon explained how encapsulation technology can deliver essential nutrients. Yeah. It's a bit like using many nutrient-packed parcels that help increase the bioavailability of nutrients.

5:49He even worked on a fascinating project that involved the use of carotenoids and liquid nanoparticles for eye health. So recently we did a project, we're trying to do like personalized nutrition. So like in the elderly, they have a disease called macular degeneration, which is like they don't get enough carotenoids in the eye and that can make them go blind. And these carotenoids act as like a natural sunscreen. So they screen out blue light. So we've developed these like plant-based eggs, which are fortified with these carotenoids. So I think it's a carotenoid called lutein.

6:21And we've shown that we can make it bioavailable so it gets into your bloodstream and it gets travel to your eye. His work really brings a whole new meaning to thinking outside the lunchbox. I love that Dr. McClemon has a dual purpose, promoting sustainability by developing plant-based alternatives to animal-based products, as well as addressing real-life health concerns. Me too. While the benefits of these innovations are clear, there's also a side of food science that can leave consumers feeling a bit uneasy.

6:52Science, especially when it comes to food, can be surrounded by controversy. Dr. McClemon discusses his experience with disputes over the ethical aspects of using nanotechnology in our food. A few years ago, there was an article in one of the Boston newspapers about some of the work I was doing on nanotechnology. And I think there was a lot of adverse comments from the readers of the journal saying, this is frankenfood, why are we messing around with our food? But if you look at nanoparticles, they're naturally no food anyway. So if you look at something like milk, it has these tiny protein particles in there called

7:23casein micelles. And it also has some sort of, if you look at fruits and vegetables, you often have these little tiny nanoparticles called oil buddies in. So what we're doing is we're just trying to mimic what is already present in nature. But again, if you are making, you know, sort of radical changes to foods, it is really important to test the safety. So, you know, we do try and understand what's happening, you know, in the gastrointestinal tract and what potentially adverse effects it could have on us. It's a great reminder that scientific innovations can be perceived in different ways. So it's essential for good intentions in science to be backed up by thorough testing

7:57and transparency. And that transparency is so important, especially when it comes to informing the public. Dr. McClemmons discussed how scientists need to communicate both the benefits and risks of their work to avoid unintended consequences. Let's hear more about a sauce on this responsibility. Science is always controversial. You know, and I think we, as a scientist, you're trying to advance knowledge. And, you know, like the Oppenheimer film, they did an amazing job at understanding sort of atoms and nuclear forces and things like that.

8:27But they ended up creating a bomb that killed tens of thousands of people. Your science can have adverse effects. I think in the food industry, an example would be like that trans fats. They created trans fats to try and replace animal fats because they thought they were healthy for you. But it turned out that they actually caused heart disease. So after, you know, like 10 to 20 years of using these, lots of people died probably from heart disease. So again, it's really important to, you know, understand the good side and the bad side of what you're doing and try and inform the public and policymakers so they can make informed

8:59decisions about it. Dr. McClements also shared his views on more recent advancements, like gene editing and precision fermentation. Here is Dr. McClements talking about the potential of gene editing and how precision fermentation could transform food production. I think things like gene editing is going to be really important. You know, things like agricultural crops. The world population continues to grow. We've got global warming and climate change. So some of the crops we could grow before, we may not be able to grow now, so we have

9:29to make them more resilient and we have to increase the yield so we can feed everybody. As long as they're proven to be safe, I think gene editing can really help making crops, you know, increase the yield, increase the resilience, things like drought and flooding and things like that. So I think that's going to be a really critical one, gene editing. I think the other one is like precision fermentation is using microbes to sort of produce different types of food ingredients. And things like lab-grown meat as well is, again, growing meat in a fermentation tank. So you take animal cells and you can grow them up into foods, which can save a lot of land

10:02and reduce pollution and reduce greenhouse gas emissions. So I think there's a lot of sort of biotechnology is going to be really important. It's a delicate balance, isn't it? Science offers us incredible tools, but they need to be used thoughtfully. It's clear that while the future of food science is full of potential, it's also essential to approach these innovations with a mix of curiosity and caution. By keeping consumers informed, scientists like Dr. McClements make sure that we're not just following the latest trends, but also making decisions that are truly good for our

10:34health. With all of Dr. McClements' work in this field, I would love to hear if his relationship with food has changed in any ways. Take it away, Dr. McClements. I think, I mean, I'm not a really good cook. You know, I am treating my professional. I'll eat a lot of processed foods. You know, if I'm left to my old devices, if I can microwave it, I will. So I'm all about, you know, producing, you know, higher quality processed foods. Because I think one of the big criticisms of the food industry now is ultra processed foods, which are causing like chronic diseases like diabetes and obesity.

11:05So I do think we need to redesign foods. So I do think about that a lot when I'm eating food and I do check labels, you know, like how much saturated fat's in there, how much sugar's in there. And when I take tablets, I'll always take them. Like if I take dietary supplements, I'll always take them with food because a lot of my research shows that if you eat food, it creates an environment in your gastrointestinal trap, which increases the absorption of vitamins and minerals. Wow, I never knew that. I've been taking vitamin D gummies for the past few years, but I usually just eat them at random times whenever I remember.

11:37I'll definitely keep that information in mind and start eating them with food. Who would think that such a small decision, like when you eat a dietary supplement, can actually affect your health? Speaking of making decisions that are good for one's well-being, Dr. McClements discuss what we as consumers can strive to do to maintain good health. Be mindful eaters, try to stay away from lots of snacks and soft drinks that are full of sugar, because, you know, as I was saying before, the modern diet is causing lots of health problems. So that, you know, like obesity is rising in America and around the world, diabetes is

12:09rising, and a lot of it's due to the foods we eat. And part of the problem is just foods are too convenient, they're too affordable, and they're too delicious. So, you know, and they're really easy to eat. And I'm the same, you have like a bag of snacks in your kitchen, you, I'll just eat the whole lot, so I just have to not buy them, otherwise it's hard to resist. So yeah, I think the most important thing is to be mindful eaters, look at labels and try and, you know, try and eat fresh fruits and vegetables, and prepare foods at home if you can, or choose healthy choices if you're going to eat processed foods. That's what my father says too.

12:41He advises me not to buy junk food, because if you do, you'll have to eat it or share it eventually. And chances are, it's going to be detrimental to your health. Plus, as Dr. McClemmons mentioned, it can be very difficult to see a bag of snacks and just not eat it. Just earlier today, I was heavily debating whether or not to open a bag and eventually decided not to, or at least not today. Haha, so true. Another part of being a mindful eater is understanding what goes into the food you eat and how it was created, and making thoughtful decisions based on that.

13:12Aside from its immense negative effect on the environment, livestock production can also be harmful to safety and health due to zoonotic diseases and antibiotic resistance. You may be wondering, what are zoonotic diseases? Great question. Zoonotic diseases are infectious illnesses that can pass from animals to humans, like rabies, Ebola, the Zika virus, and countless others, and they're very common. As a matter of fact, about 60% of known infectious diseases and up to 75% of emerging or new infectious

13:43diseases are zoonotic. Wow, I didn't know it was that high. As for antibiotic resistance in livestock, that's when the animals are fed antibodies to prevent them from getting sick from bacteria, but the bacteria that have a random mutation, making them resistant to the antibodies, reproduce and pass on that gene to their offspring. Eventually, the bacterial population as a whole can become resistant to the antibodies. All of this makes it even more important to develop plant-based foods. And given how complex food science is, the more scientists that work in it, the better.

14:17Here's more from Dr. McClements on that. The more I work in this area, the more challenging it seems, and the more, you know, fundamental science, scientists we need to work in this area. So I would love chemists and physicists and polymer scientists to treat food as like a subject that they would be happy to work on. I think a lot of people think food, oh, it's not like proper science, but I think it's incredibly complicated. And we really need those fundamental scientists to work in this area. Indeed. When scientists from different fields collaborate, they bring their own distinct knowledge and

14:49skills to the table. So the team as a whole can more thoroughly understand situations and problems and come up with an even more effective solution. And when you're working in an area like plant-based foods, those solutions can end up being used by millions, maybe even billions of people. Let's hear more from Dr. McClements on some of those possible solutions. It seems you can just take two polymers, like a protein and polysaccharide, and mix them together and you can get all sorts of different textures. You can make them transparent or you can make them opaque.

15:19You can make them really hard or really soft just by changing the pH or temperature to change the molecular interactions between them. I think one of the things I'm most excited about recently is, you know, people tend to eat either these sort of meat analogs or egg analogs, or they tend to eat like tempeh or tofu to get their protein. And I think there's a lot of nutritional problems from vegans and vegetarians who don't get enough proteins in the diet. I think there's often nutrient deficiencies as well, like vitamin D and vitamin B12 and zinc and other minerals as well. And a lot of people don't like the meat analogs or the traditional things like tofu or tempeh

15:53or seitan. So we're trying to create this whole new category of protein rich, nutritionally fortified foods that just don't exist now. So we can make, for example, like a red cube or a purple sphere or a yellow cylinder, and we can make it hard or soft. We can make any nutritional profile. So we're trying to, it's almost like this molecular gastronomy approach where we're creating this whole new generation of foods that are designed for health and wellness and sustainability. But the problem is, will anyone eat them? So I think we have to do a lot of consumer science to see if people will actually accept any of these foods.

16:24That would certainly be interesting to see. Just imagine going to a restaurant and ordering a large red cube with a side of mini yellow cylinders. It would definitely take some time to get used to. The taste would be a crucial factor as to whether or not people will eat it. If the new food tastes good, it would probably be pretty successful, despite it being a big change. But first, people would have to know about it. And one way that can happen is by reading books on the topic. Yes. In fact, Dr. May Clements is the most highly cited author in food science in the world.

16:56So it's no surprise that he's written quite a few books and articles on the subject. Take it away, Dr. May Clements. The thing I like most about it is you learn a lot because you have to really read around the subject and you have to put it together. So it really helps you learn about the field. So I wrote some books at the beginning of my career, and I think that really, you know, gave me a lot of knowledge and I'd sold in all the gaps that I didn't have. And that's been really useful and also useful to get my industry contact. I mean, the one that I like the most is one called Future Foods. You know, and I was really focusing on sort of food nanotechnology. So it's really sort of narrow area.

17:28And I just thought there's so many exciting things going on in food science at the moment in all sorts of different areas, like genetic engineering, precision fermentation, nanotechnology, structural design, food architecture, stuff like that. So I just thought, you know, I'll write a book on this. And I, again, I learned a lot about this area. I really enjoyed it. I should also say that my daughter just started a PhD in organic chemistry. I actually just wrote a book recently with my daughter and with my nephew called How to Be a Successful Scientist. So that was really exciting. You know, she just finished her first semester last year and just she used to start her second

18:02semester in her research. So she's really excited about chemistry. That's so cool. How to Be a Successful Scientist is out now. And it gives important advice for scientists at all stages of their career on experiments, scientific manuscripts, soft skills, and much, much more. Great. Speaking of advice, let's wrap up this episode with some of Dr. McClemmen's advice for students.

Advice for Students

18:26If you're not interested in what you're doing or you're not engaged in what you're doing, it's really hard to do work. Be persistent. Things often go wrong. And that's normal. And sometimes that's where you make the most interesting discoveries. And I think for me, if it's graduate work, I always say, think about the paper you're going to write first and design it all out before you can start the experiments. Because that can really help you sort of narrow down the scope of your work and have a really good focus. And it helps you determine what's the best methods to use. And it stops you just doing like hundreds and hundreds of experiments and then not knowing what to do with the data.

18:57You've got a really well-defined project. I totally agree. If you really don't care that much about what you're doing, then it can become tiring and much harder to stick with, especially when things get rough. Exactly. I also think his advice on designing the paper and thinking of the end result before you start working is quite insightful too. Having a clear plan and goal set ahead of time can help you stay on track and understand why you're doing what you're doing. Also, you'll think more deeply about the best methods to get the specific results you're

19:28searching for. Definitely. Thank you so much to Dr. McClements for sharing your knowledge and advice with us. And to all our listeners, thank you for joining us. Until next time, I'm Porphy. And I'm Elizabeth. See you all on the next episode of Let's Talk Chemistry. Bye. Thank you for listening to Let's Talk Chemistry, a podcast by Chemtalk. We hope you enjoyed it. For more information on today's episode and countless chemistry resources, please visit our website at www.chemistrytalk.org.