Linn Steward and I have been discussing online the importance of the food matrix. She is a true believer. I am a skeptic. She sent me links to three articles that introduce the concept. The gist of the issue is that as we break down whole foods into component parts, we lose ingredient quality. She sent me the question below that I will attempt to answer.
Linn: It seems to me we live in an era of fractionated-recombined foods. Two examples come to mind—Beyond Meat Burger & Kind Bar. These industrial formulations consist of pieces and parts of foods like yellow split peas or fresh apricots which have been subsequently broken down into small parts. Yellow pea reduced to protein isolate. Apricots reduced to slurry. Food scientists can take a yellow pea or an apricot apart. But when the isolate or the slurry gets put back into the burger or the snack bar, something has changed and something has been lost. It’s like the old nursery rhyme about Humpty Dumpty. Please comment on what might have been lost in the process.
Rob: Your question is complex. It helps to narrow it down to two representative ultra-processed products. I base my answer on many facets of my educational/professional career. As a food scientist I am a reductionist. We approach food from its susceptibility to microbes and its chemical composition. In the best nutrition course I ever took in college, I took a special interest in digestion. My dissertation research focused on intercellular activity of fish muscle tissue. As a postharvest technologist/physiologist I looked at cellular structure in plant tissue. As an instructor of Food Chemistry, I focused on functional properties of ingredients. When teaching Food Processing, I emphasized the specific steps leading to a finished product.
Let’s start with Beyond Burger. It is ultra-processed because it contains forbidden ingredients. NOVA condemns it. The forbidden additives include binding agents and purified protein. All ingredients are plant derivatives. Beyond Burger did not exist when NOVA was born. It was not coded in many if any of the studies correlating health risks with ultra-processing. It is guilty by association based on an arbitrary classification scheme.
The ingredients in Beyond Burger are
Water, pea protein, expeller-pressed canola oil, refined coconut oil, rice protein, natural flavors, dried yeast, cocoa butter, methylcellulose, and less than 1% of potato starch, salt, potassium chloride, beet juice color, apple extract, pomegranate concentrate, sunflower lecithin, vinegar, lemon juice concentrate, vitamins and minerals (zinc sulfate, niacinamide [vitamin B3], pyridoxine hydrochloride [vitamin B6], cyanocobalamin [vitamin B12], calcium pantothenate).
Each ingredient has a function as do ingredients in a home recipe/formulation. The pea and rice protein combine to provide a balanced protein. The unsaturated oils replace the saturated fats in the meat burger. The beet juice and pomegranate concentrate contribute to color. Apple extract produces browning. Cocoa butter includes fat and suggests marbling of the meat. Methylcellulose and modified starch bind ingredients together to provide a proper consistency. Salt adds flavor. Added vitamins and minerals improve the nutritional profile of the product. Note the pea protein is present as a protein isolate. As such it is more concentrated than eating fresh or cooked peas. Consumers allergic to peanuts could be susceptible to higher levels of pea protein.
Your concern seems to be with pea protein isolate. There are many different ways to isolate proteins. The probable steps in the process from pea to isolate will go something like the following:
- Clean the peas to remove other seeds such as wheat or barley,
- Split the peas and remove the hull,
- Soak and grind the peas into a slurry,
- Adjust the pH with a base to pH 9.5-10.5 to isolate the protein,
- Extract carbohydrates using ultrafiltration,
- Precipitate the protein in acid (pH 4.0-5.0),
- Centrifuge or filter to separate the protein from undesirable components,
- Wash the isolate to remove residues from the liquid, and
- Neutralize the pH to 7.0 and spray dry to a powder.
The resulting protein isolate is over 80% protein. The amino acid balance is excellent. Pea protein functions to bind fat, emulsify, and stabilize the burger. The isolate retains some dietary fiber and some folic acid. The purer the protein, the less fiber, vitamins, and minerals remain. What else have we lost in the process? Most of the flatulent-producing oligosaccharides, stachyose, and raffinose, are gone. Also lost are the anti-nutritional factors such as lectin, phytic acid, and oxalates. Any hydrolysis of the protein is only incidental. The goal of the process is to keep the protein intact rather than to break it down into component amino acids.
Processors combine modified ingredients to improve their acceptability of the cooked burger. I compare the Beyond Burger to a regular hamburger. First, we lose the off-flavors. Intact or rehydrated yellow peas contribute to undesirable flavors. The color and texture of the plant-based burger is not the same if whole peas are present. The plant protein substitutes for animal protein. Using isolates means less dietary fiber, but the burger eater doesn’t expect fiber in the burger. Vitamins and minerals are important additions. The vitamin, mineral, and protein profile is good. It is higher in sodium and saturated fatty acids than it could be.
The developer would claim that a Beyond Burger is a new and improved version of Humpty Dumpty. The burger gains better color, flavor, and texture by adding the modified ingredients. Lost could be some protein, vitamin, and mineral quality when compared to the meat burger. On balance, I have no problem with isolating the protein to improve its digestibility. After snapping the photo, I pan-fried my Beyond Burgers. I was pleased with my eating experience. The burgers looked like the real thing and had an excellent texture. The flavor was better than if I had formed the patties myself and pan fried them.
It is important to understand why Beyond Burgers exist. Some vegans and vegetarians want to experience a hamburger without eating beef. The added ingredients are present to mimic that experience. Militant vegans and beef producers oppose this ultra-processed product for obvious reasons. As the world grapples with climate change, sustainable plant-based substitutes could help. I see no reason to consider Beyond Burger the functional equal of a Twinkie. Both products classify as ultra-processed under NOVA.
Linn: First off, thanks to Rob for explaining how a food scientist isolates a protein. The process as described above has similarities to the process of digestion. This similarity has not been ignored by CEO Ethan Brown when he refers to the Beyond process as a new way of creating meat by collecting plants a cow would graze on, then deconstructing and reconstructing the components in a laboratory.
From my reading of the literature, the research on the healthiness of intact (minimally processed) and unhealthiness of ultra-processed foods is only just beginning. One thought did occur to me, however, as I was thinking about how Ethan Brown describes the Beyond process. Human digestion requires calories. This process has a name Thermic Effect of Food (TEF). I haven’t seen any studies yet comparing the TEF for a ground beef patty and a Beyond Burger, but I’m wondering how the numbers would look.
Taste is always 100% subjective, so I can only speak from myself. I tried a Beyond Burger with lots of condiments and couldn’t taste any difference. I do like the taste of beef, however, but am fussy about origins and rarely use pre-ground. We don’t eat a lot of beef because of cost constraints. And since I make a wicked good split pea soup, I prefer the taste of my soup to a commodity burger of any kind plant-based or industrially processed.
Rob: Moving on to the Kind Bar, I see that there are several options out there that have apricots as an ingredient. I will use the Almond & Apricot Fruit & Nut Bar as a basis for answering your question. I was unable to find a Kind Bar with apricot in it for sale now, not even on the Kind Bar site.
Ingredients: Almonds, coconut, honey, non GMO glucose, apricots, apple juice, crisp rice, vegetable glycerine, chicory root fiber, soy lecithin, citrus pectin, natural apricot flavor.
Nutrition: 180 calories, 10 g fat (3.5 g saturated fat), 25 mg sodium, 23 g carbs, 3 g fiber, 13 g sugar, 3 g protein.
Multifunctionality of these ingredients is impressive! I am guessing some on this breakdown, but here is my assessment. Honey, apricots, and apple juice provide sweetness. Glucose is not sweet but contributes to sugar level. Almonds, coconut, crisp rice, and chicory root make the bar crunchy. Honey, glucose, apricots, glycerine, and pectin help bind the bar together. They also contribute gooeyness. Fiber comes from almonds, apricots, chicory root, and pectin. The soy lecithin acts as an emulsifier. Apricots are all-star ingredients. They function as a sweetener, binding agent, humectant, and flavoring agent. Binding agents, humectants, and flavoring agents are on the list of forbidden ingredients. Apricots allow the Kind Bar to skirt these rules. What confirms this 12-ingredient food as ultra-processed are four forbidden ones. Non GMO glucose, vegetable glycerine, soy lecithin, and citrus pectin are unacceptable.
I am not sure of the form of the apricots in the product. I imagine that they use dried and chopped fruit. Apricot puree is a possibility, but that should appear on the label if so. When you mention intactness of ingredients, how intact do you need? Let’s switch to canned tomato products for a minute. I find whole, chopped, diced, stewed, puree, sauce, and paste on the store shelf. Where on this continuum is it no longer intact? Does it make a difference if the breaking down of the apricot or tomato happens in a plant or in a home blender?
What do we lose when we cut up an apricot? We lose cellular structure. Breaking up plant cells release acids and enzymes from the vacuole in the center of each cell. The enzymes in fruits attack the cell walls leading to browning and some loss of fiber. The same thing happens during chopping of vegetables. The more we chop, the more we destroy cells. I am not sure that nutritional quality is much affected. Some volatile compounds escape the matrix which could enhance or degrade flavor.
Linn: How intact do I want my ingredients? That one is easy to answer. I want my apricots whole, in season, tree-ripened, and locally grown. Living in the northeast, I have fresh apricots during a short approximately 6-week season. For the rest of the year, I’m happy with the next best apricot – whole, dried, and unsulfured.
Rob: The developer of this Kind Bar reconfigured Humpty Dumpty for stability and convenience. Your fresh apricots will be delicious for a few days before starting to decay. If you forget them on your kitchen shelf or in the back of your refrigerator, they will become inedible. The almonds will last longer but will stale and oxidize in time. If you carry the apricots and almonds in your pants pocket, there will be consequences. Besides becoming a gooey unappetizing mess, they could become contaminated by harmful microbes. The Kind Bar provides a healthy convenient snack when on the go. It lasts longer as the ingredients work together for that purpose.
I see merit for a chef in keeping whole, fresh ingredients intact. Grinding of fatty meats opens up cell structure increasing fat rancidity. Cutting and blending of fruits or peas releases flavor volatiles and accelerates browning. Combining of ingredients halts undesirable changes in sensory quality. Quick cooking of deconstructed meat, legumes, or apricots achieves the same goal. But how do you please a vegan who wants a meat dish without adding in some forbidden ingredients?
The purification process required to isolate proteins from other components also concerns you. These ingredients are not acceptable to NOVA and not desirable to you as a chef. It doesn’t bother me that an industrial formulation contains a purified protein as an isolate. Homemade tofu is a derived protein concentrate. By the same reasoning, it should also be a forbidden ingredient. Glucose, glycerin, pectin, and lecithin are natural components of other foods. Why are they not permissible in a ready-made item off the shelf? Home cooks and restaurant chefs receive more leeway with ingredients than food processors.
Linn: You and I are on the same page regarding the use of food technology and the need to keep up with population growth and a changing climate. Technology is just a tool. It’s how we decide to use the technology that counts. Aggressive marketing, advertising, ignorance, and good old fashioned human greed always complicate the issue.
Rob: Well said.
Next week: What dietitians and food scientists need to know about each other by Trey Sanders
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