Advances in the science and technology of plant-based proteins

What a primer on food chemistry and biochemistry! I had not encountered this much technical depth since my days in grad school. I envisioned nightmares of proteins folding and unfolding in my sleep! Dr. John Brandts tried to teach me about the Physical Biochemistry of Proteins. It was the most difficult course I ever took in college. I read Next Generation Plant-based Foods by McClements and Grossman. I was fortunate that the protein nightmares didn’t come.

The book chronicles the emergence of plant-based proteins as ingredients in food products. It also focuses on a path to a more sustainable future paved with these proteins. To gain general acceptance these molecules must clear some major hurdles. The authors emphasize strengths and limitations of the types of products available today. New technology is on the way! The authors look to future applications of these novel ingredients. Will we see more plant-based proteins in our future or will it be a mere passing fad?

David Julian McClements is a food-science superstar. He is a prolific author of journal articles. His research interests encompass nutrient uptake in the gut, food biopolymers, and food nanotechnology. His office is a 3-minute walk from the classroom where Dr. Brandts terrorized me. I reviewed another book by Julian last year and indicated that I know him but not that well. He leads the way in studying the controversial revolutionary ingredients—plant-based proteins.

picture of Food Science Building
Chenoweth Hall. Home of Food Science at UMASS and location of Dr. Julian McClements office.

Why plant-based proteins? The short answer is that they are good for the environment and provide protein to people who don’t get enough. A consensus of climate activists recommends less reliance on animals grown for food. Clearing land to pasture grazing animals cuts into wildlife habitat. Feedlots reduce the need for more land but at a cost of animal welfare and increased pollution. Animals also contribute to higher carbon and nitrogen emissions. Such ideas meet resistance by animal activists and advocates of regenerative agriculture.

Not everyone consumes enough protein to thrive. Progress against world hunger narrowed the hungry population to 12% around the world. Most of the hungry live in Asia and Africa. The most endangered of them are under 5 years of age. These numbers show a much-improved state of world hunger in the last 50 years. Are we ready to declare victory and walk away? Or do we look for ways to increase protein sufficiency in poor nations? Plant-based proteins increase consumption of high-quality protein without food from animals. Insects and fungi offer other, less expensive alternatives.

Barriers to plant-based products. Development of high-quality plant-based products to replace animal-based foods faces many challenges. ‘Taste’ (82%) is the number one driver of consumer behavior when it comes to fake meat, eggs, etc.

Time out!!! As a food scientist who dabbled in sensory evaluation in my career, I can’t let the description of taste go. What normal people call taste, food scientists call flavor. Taste includes the sensations of sweet, sour, bitter, salty, and umami. Flavor adds the sense of smell to the equation. Think of all the different aromas we encounter everyday associated with food. It’s not taste that distinguishes one food from another. It is the combination of taste and different aromas. A product developer matches taste sensations with careful attention to detail. It is the aromas that constitute the real challenge.

After flavor, cost (66%), health (58%), and convenience (52%) command the attention of home cooks. The clientele cooks must please are the families they feed. Sustainability (31%) comes in fifth on the list of desired characteristics. Critics of the alternative products point out that sustainability doesn’t sell. Note, though, that the top five drivers of acceptability add up to 289%. The sustainability customer may have a strong commitment to the cause. If a product meets one or two of the other drivers that may be enough for sustainers to become regular buyers. Meeting at least two criteria by those not interested in sustainability is necessary.

There are other barriers to widespread adoption of products featuring plant-based proteins. Ingredients must be low-cost and available in the supply chain. Besides, they must be of consistent quality and label friendly. They must achieve the feel, look, mouthfeel, smell, sound, and taste of the real thing. Problems with first generation plant proteins include batch inconsistency, off-flavors, and poor solubility. Designers of these items must also consider carbohydrates, fats, and food additives. Each ingredient in a formulation or a recipe has a specific function in the resulting food. Success or failure of a product or a meal depends on each ingredient performing its function.

And that is not all a developer must consider. Plants contain both nutrients and antinutrients. The presence of these molecules in a food affects bioavailability and biopotency. Extracted proteins may have nutrients and antinutrients attached. Attached molecules concentrate with the extracted proteins. Ingredient manufacturers must work to limit natural antinutrients. Also, some nutrients limiting in plants include iron, calcium, zinc, and vitamins B12 & D.

A multidimensional approach. Developing processes to extract proteins from plant materials represents only one challenge. Designing new products to incorporate these ingredients into acceptable food products is the next obstacle. Evaluating the acceptability in the mass market follows. Can the products compete on flavor, cost, health, convenience, and sustainability? New plant proteins from chickpeas, sunflower, and other crops represent alternative ingredients.

Products emphasizing plant-based proteins will qualify as ultra-processed foods. About 60% of American foods qualify as ultra-processed. It is clear that Americans don’t reject ultra-processed products outright. Products containing plant-based proteins consist of more than 5 ingredients. Designers of plant-based products must keep the ingredient list as short as possible. Ingredients must have familiar names. Ingredient stability before, during, and after processing is critical for product success. There is a lack of a technical base of information to integrate process operations. Skeptics should not count out such foods yet. Food science is advancing to make these products part of the American foodscape.

Types of products available. Most products containing plant-based proteins are imitations of animal-based foods. Examples include eggs, meat, milk, and other dairy alternatives. Why not try to get people to eat traditional plant-based foods? The answer is that most people want to eat foods that are familiar to them. Try getting someone to adopt a dietary pattern of unfamiliar foods. Americans may try them out at first, but they tend to revert to a more familiar diet. The Millennial and Zoomer generations seem to be more willing to try new foods. Does this attitude represent a generational trait or the openness of young people? Time will tell. Note, these generations are also more interested in sustainability and health.

I am on a mission to try products containing plant-based proteins. I want to reduce my ecological footprint. None of the plant-based milks I tried ever appealed to me. I also investigated plant-based cream cheese. I do not like to throw away foods I don’t like, but the cream-cheese alternate did not make its way to my mouth a second time. I have incorporated plant-based meat products into my cooking at home. The Impossible Burger was good before I started going gluten-free as long as I ate it while hot. Beyond Burger is so much easier to prepare with a nice grilled flavor. The health aspects are superior to the benzopyrenes found in a grilled burger or steak. Beyond Beef Plant-Based Ground is a suitable substitute for ground beef. I use it in spaghetti sauce, hot-dog chili, and chili rellenos.

My recent trial of plant-based chicken and egg products did not go as well. The chicken substitute came before the egg. My Plant-Based Chicken Style Bites were a soggy mess. I cooked them in chicken soup made with chicken broth, carrots and potatoes. To be fair, package instructions recommended stove-top frying or microwave heat. I wanted chicken soup not chicken chunks. Just Egg did not deliver a much better culinary experience. My first trial gave me a very strong pea flavor (not taste). Disgusting! I tried it again with two Just Eggs and one real egg. The real egg covered up much of the objectionable pea flavor. Then again that sort of defeats the purpose, doesn’t it? “Are you through with your experimentation with these products?” asked my wife a week or so ago. I cook all the meals in my household. I guess I am not meeting the expectations of my clientele.

Which came first the plant-based chicken or the plant-based egg?

The future of next-generation plant-based proteins? First, the flavor, appearance, and texture must improve. Alternative meat, egg, and milk products meet or exceed expectations of potential consumers. The move of alternate meats into the meat section may not have been a smart move. The convenience of a frozen product trumps the appearance of fresh meat. Next such products must meet a price point comparable to the fresh alternatives.

The loss of sales of plant-based meats signals the collapse of all plant-based foods. Or so we read. Not so fast! Plant-based milks are increasing in sales relative to traditional milk. Note that increasing regulations of animal farms suggest major increases in meat prices. The fight over nitrogen emissions in the Netherlands may only be the beginning. Too rapid an introduction of these ingredients into the market may be a stumbling block. I am reluctant to try newer versions of alternative milks and eggs. I imagine new-and-improved versions of these products will find a way into my diet in the future. Will other disappointed consumers re-enter the market?

Quibbles. I have nothing but admiration for the depth and scope of the basic food science described in this book. I do have some concerns when it comes to sensory quality and color measurement. These were two of my research specialties. I have been out of the field for almost a decade. I know of no protocol in sensory science to meet the needs for evaluating these products. Success or failure of next-generation plant proteins depends a useful form of measurement.

Hedonic scales will not give McClements and associates the information they need. I proposed a 3-point acceptability scale, but I am not sure that is what they need either. I recommend that Julian develop a close association with an adventurous sensory scientist. Together they could cobble out a means of developing a new way to assess acceptability. In measuring color quality, the book relies on the measures of L*a*b*. The problem with this approach is that a* and b* are not independent measures. They influence each other. A more accurate use of a* and b* involves calculation of hue angle and chroma.

Take home lesson. Plant-based proteins have become part of the food culture wars. Chances are that these ingredients are not going to cause mass death and destruction. Yes, they will be in ultra-processed foods as replacements for animal-based protein. Less demand for animal products benefits human health, the environment, and animal welfare. This research effort focuses on increasing the healthiness of processed foods. It seeks to become part of the solution, not part of the problem. The main thrust of the book emphasizes the evolution of food technology to meet future needs. Kudos to the McClements lab in advancing research on plant-based proteins.

Next week: Technically Food, a look at the future of venture capital for new foods

7 thoughts on “Advances in the science and technology of plant-based proteins

  1. Thank you Dr. Shewfelt for continuing to inject common sense and food science into our lives. The plant-based foods explosion over the past 5 years has left many consumers confused. I’m sure your readers really appreciate, as I do, the way you credibly communicate back and forth between the big picture and specific elements of chemistry, biochemistry and organoleptics. Animal meat and milk alternatives have come a long way in the last couple years, but frankly, egg and cheese alternatives still need a lot of Food Science. Looking forward to your next blog.


    1. Thank you very much for your comments. If memory serves me correctly, I had the pleasure of visiting your product development labs almost a decade ago in Brunswick. I was very impressed with the facility and the approach you were taking! Yes, the consumer is confused! I am confused! That is why I am trying to learn more about this intriguing area of food science. You have convinced me to try some plant-based milks again. I was surprised at the flavor of the eggs and cheese that I sampled. Over the next two weeks I will look at the skeptic’s point of view on the issue of plant-based foods.


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