Plant Protein: New Sources

October 9, 2012

Plant protein types are diverse, from alfalfa and oat to pea, rice, wheat germ, and more.

Plant protein types are diverse, from alfalfa and oat to pea, rice, wheat germ, and more.

The nutritional benefit of protein doesn’t often come into question. But the same cannot be said of protein sources. Traditional protein sources-i.e., meat and dairy-are seeing fluctuations in both price and consumer preference. USDA statistics reveal the per-pound price of dry whey has doubled in the last three years (from 26¢/lb in 2009 to a projected 55-57¢/lb this past August),1 and annual meat consumption is now at its lowest level in 20 years (just 170.6 lb per person compared to an all-time high of 184.1 lb in 2004).2 Accordingly, manufacturers are looking elsewhere.

So what’s bringing up the slack in animal protein intake? Plant protein. And not just soy. Low-allergy plant foods that boast high protein levels-there are many-are proving environmentally sustainable, available in high supply, and beneficial for nutritional components beyond just protein.

Of course, plants don’t always provide the same quality of protein as animals do. When lacking in one or two of the nine essential amino acids-the ones humans can’t synthesize and must obtain from the diet-these plants are referred to as “incomplete” proteins.

Here’s where ingredient suppliers come into play. Modern processing technologies now enable the production of “complete” protein, even from “incomplete” proteins, by concentrating up all amino acids in the plant source. Let’s focus on a few of these ingredients.

 

Alfalfa Protein

Much like the soybean, alfalfa is a legume with available protein. When eaten sprouted or as seeds, a cup of alfalfa accounts for roughly 1 g of protein.3 But processing technologies-clean processing technologies-can draw out more alfalfa protein in a concentrated form.

Ingredients by Nature (Montclair, CA) is one of the pioneers of concentrated alfalfa protein. Its AlfaPure ingredient guarantees at least 52% protein content compared to the roughly 10% found naturally in alfalfa. This is done using the company’s ProZam method, a 100% mechanical process that strips alfalfa of much of its fiber, phytoestrogens, saponins, and other unwanted compounds without the use of chemicals, additives, or carriers. And after pressing much of alfalfa’s fiber out of the final product, AlfaPure still has a bonus of up to 14% RDA of dietary fiber per serving, says the company.

The resulting complete protein is especially high in essential amino acids methionine and lysine, which company president Rob Brewster says are normally the first to go when switching from an animal to plant protein.

Alfalfa protein has one major formulation challenge: green color. But this chlorophyll-rich ingredient can do more than fit into green food blends.  Other nutritional benefits of alfalfa protein are high sources of vitamin K, carotenoids (beta-carotene, lutein, and zeaxanthin), calcium, and omega-3 and omega-6.

 

Oat Protein

Oats are best known for their high fiber content (hence the heart-healthy reputation), but they happen to be one of the world’s most protein-packed grains. In fact, a cup of cooked oats provides about 11 g of protein.3

With that in mind, Biovelop (Kimstad, Sweden) sought to separate the protein from oats, just to add to the company’s already substantial business in oat beta-glucan (a soluble fiber) called PromOat.

After spending years developing chemical-free processing technology, Biovelop is now capable of fractionating, or separating, oats into their constituent parts, and then selling each part individually as insoluble fiber, soluble fiber (PromOat), the sweetener maltodextrin, and protein (dubbed prOATein).

Available as a fine beige powder, prOATein is especially high in essential amino acids leucine and lysine, although the ingredient tends to be marketed as a “complete” protein above all else. It tastes, unsurprisingly, like oats, and is therefore best suited for products in which oat flavor is desired. (One of Biovelop’s customers even uses prOATein to make oats taste oatier.)

Aside from protein powders, oat protein is best suited for baked goods and other grain products, says Biovelop executive director David Peters. (A completely water-soluble version has yet to be developed.) “For protein bars, this ingredient is great,” he says. “Along with the protein content, our ingredient also contains an element of oat oil. And because bar manufacturers often have to add fat to give bars that chewy texture, the fact that our ingredient has oat oil in it means manufacturers can significantly reduce the amount of additional fat sources.”

Another interesting use for oat protein is taking place in bread, as so-called functional breads with enhanced fiber and protein content are emerging in Europe.

Back to the oat oil, prOATein can even enhance formulations for healthy pet fur or human skin. Peters says, thanks to the oat oil’s rich source of omega-6, the company’s ingredient has already developed a calling in the pet food industry.

Biovelop’s oat ingredients don’t travel far to reach the company’s Swedish headquarters. In fact, the oat farms surround it in the Ostergotlands region, where oat farming has remained a tradition for hundreds of years.

 

Pea Protein

This little legume packs enough protein to rival other plant sources, as a cup of peas equates to 3 g in protein.3

Typically sourced from North American yellow peas, pea protein does run the risk of carrying beany notes similar to those of soy protein, so cleaning up the taste of pea protein has become a key initiative (and achievement) for suppliers.

Employing a clean processing technology is just as important, says Johann Tergesen, president and COO of Burcon NutraScience Corp. (Vancouver), which supplies Peazazz pea protein.

“Proteins can be damaged (denatured) easily by heat, pressure, or chemicals,” he says. “We use a wet processing environment, and we try to be gentle, whereas, if you look at traditional soy isolates as an example, the predominant method uses a very high pH, meaning an alkaline environment that’s very harsh. Our process works in a very neutral pH range. We solubilize the protein in the solution, treat it gently, don’t overheat it, and don’t add too much chemical.”

As a complete protein, pea protein happens to be especially rich in arginine, compared to other protein sources. This essential amino acid is known to support antioxidant defenses and promote heart health through the creation of nitric oxide.

Pea protein also comes with sustainability benefits over some other plant proteins. According to Nutralys pea protein supplier Roquette (Lestrem, France), the pea plant, like other legumes, is “autogamous.” This means that its external pollen doesn’t require fertilization because it can actually draw nitrogen from the air. When used in rotation with wheat (another autogamous crop), fewer greenhouse gases are released into the atmosphere.

Just remember: all finished pea proteins are not the same. In fact, Burcon NutraScience recently made its Peazazz pea protein completely water-soluble. When asked which plant proteins are not completely water-soluble, Tergesen said, “Virtually all of them.”

 

Rice Protein

The rice plant is a complete protein in nature, but Axiom Foods (Los Angeles) president and CEO David Janow says rice is incomplete in the way we typically eat it.

“Brown rice is good for health, but it’s still missing a lot of the components,” says Janow, whose company supplies Oryzatein brown rice protein. “It doesn’t have the germ and it doesn’t have all of the bran on it-it can’t, because fatty acids in it will run the product rancid.”

Compared to the usual hexane extraction of protein from just the bran component, Janow says Oryzatein utilizes every part of the grain-the bran, the germ, and the endosperm-without chemicals or pesticides.

So what’s driving the market for rice protein? Janow says it’s the gluten-free market, where protein is still lacking from the loss of gluten. Rice’s bland taste and grain character make it especially suitable for baked goods and other grain products, with or without gluten.

 

Wheat/Germ Protein

For applications where wheat is desired, wheat germ and wheat protein are strong candidates.

“Wheat germ represents only a small (2.5%) portion of the wheat kernel, but it contains the highest concentration of proteins, vitamins, minerals, and oil,” says Laxman Singh, senior vice president of R&D at Vitamins Inc., which manufactures wheat germ for Prinova (Carol Stream, IL).

To add wheat germ to most food products, the wheat germ must first be defatted. This process of removing the oil from the ingredient substantially lowers its risk of becoming rancid. Nutty in flavor, defatted wheat is usually available in a variety of particle sizes-from fine powders to extruded nuggets that are good for granola or toppings-and toasted or untoasted. Preferential applications for defatted wheat germ are, of course, in products where wheat is already being used, including in cereals, certain protein bars, and crackers.

Several wheat germ suppliers require minimal use of chemicals for extracting the protein, but work is underway to develop cleaner, more natural processing methods.

Besides the germ, wheat protein from The Scoular Co. (Omaha, NE) is another option. This highly dispersible protein is slightly malty in flavor and rich in the amino acid glutamine, a non-essential amino acid increasingly recognized for supporting exercise recovery.

 

Protein: Ancient Grains

In recent years, the health foods sector has witnessed growing consumer interest in ancient grains. Perhaps at a premium cost, these lesser known grains have their own nutrition advantages over conventional grains and the added appeal of their exotic backgrounds. The plant protein market is now including several of these protein-rich cereal grains in formulations, including sacha inchi, amaranth, and quinoa. Expect interest to grow. 

 

References

  1. Information based on USDA statistics: www.usda.gov/oce/commodity/wasde/latest.pdf
  2. Information based on USDA statistics and compiled by the Earth Policy Institute: www.earth-policy.org.
  3. Nutritional facts retrieved from the USDA National Nutrient Database