Editor's Note: This article is part of a series on plant proteins. All stories in this series can be found here.
Among some younger shoppers, red meat is out and sustainability is in.
That’s according to Guy Crosby, science editor for America’s Test Kitchen and an adjunct associate professor at the Harvard School of Public Health.
“Younger consumers, especially millennials, are looking for an alternative for red meat, but they don’t want to give up protein,” Crosby told Food Dive.
Fortunately for them, food scientists and ingredient manufacturers have been working to find alternatives to real meat that create satisfying protein-filled foods. They’ve hit upon several ingredients that work well. Here are the top 6 plant-based ingredients commonly used in protein products.
According to the U.S. Department of Agriculture, soybeans are one of the most-planted crops in the United States — second only to corn. In 2009, there were 77.5 million acres of soybeans planted.
Why plant so many soybeans in the first place? When pressed, soybeans are a main component of vegetable oil. Some of the leftovers can be used for animal feed. But there are still other leftovers — and that in the ‘90s, Dupont led an effort to use that leftover protein for something else, Crosby said.
“Soy is also very inexpensive because it's just derived from the animal feed waste product," Crosby said. ...It's not terribly complicated to make. It can be made in huge quantities. It's being processed a lot in Canada and China, which are probably the biggest suppliers in the word. From that point of view, it's got a lot going for it."
Since soy protein was the first ingredient that food scientists really explored making into a meat substitute, it has been researched, processed and tried in different forms for the longest time. This could help explain some of the reasons that soy protein is now found practically everywhere: Currently, about a quarter of all protein consumption comes from soy, according to Crosby.
From a cost standpoint, soy is extremely inexpensive to work with, Crosby said. Soy protein is basically a waste product, so it’s readily available. This also adds to the ingredient’s sustainability. Because turning soy protein into food saves that soy from the landfill, there are few more environmentally friendly ingredients available.
Soy is also nutritious. It has a full complement of amino acids — essential nutrients that mammals’ bodies can’t make. In order to get amino acids, people need to eat them. While many other plant-based proteins don’t have everything that people need, “soy does fulfill that bill,” Crosby said.
Also in soy’s flavor: It is easily digestible by most people, and its taste can be easily seasoned to complement or mimic other food items.
But soy isn’t perfect. In the years that soybeans have been used as an ingredient, crops have been repeatedly genetically altered to create the best yields. Today, this means it's extremely different to find non-GMO soy. While most scientists say GMO crops are just as healthy as their non-GMO counterparts, some consumers only want to eat non-GMO foods — and for them, soy is often not a viable option.
In the early 2000s, Canadian farmers started producing large amounts of peas to use as protein for meat substitutes, Crosby said. In the years since, peas have started to catch on as a new ingredient.
“Pea protein has come along as probably the next best alternative,” he said. “It’s not genetically modified. It’s not too much more expensive than soy protein, although it doesn't have that big market of soybean oil. ...It’s got some good advantages.”
Pea protein can be processed in many of the same ways that soy is. These proteins can be found in many products, including Beyond Meat’s plant protein-based Beyond Burgers. However, it isn’t quite as widespread as soy — mainly because it has not been marketed as a protein substitute for as long, Crosby said. But many products that are in need of a protein jolt — shakes, snacks or protein bars — feature pea protein.
Pea protein’s taste makes it a good item for a variety of applications. “It’s considered to be pretty bland, and the processing generally works any taste out,” he said. “It’s not cited as a significant development."
However, pea protein does have some negative aspects. Crosby said it has most of the essential amino acids, but it is not as complete as soy protein. Some consumers also have trouble easily digesting pea protein, making it slightly more difficult to include in products than soy.
As far as sustainability goes, there are few plants that can compare with algae.
Grown in water and naturally occurring, algae doesn’t take much fertilizer to get a successful crop — and it doesn’t take much space or require any highly specific environmental factors.
“It's kind of like vertical agriculture, the indoor growing of greens and things,” Crosby said. "You can do it in an area that isn't taking up agricultural land and resources."
Food scientists have recently been able to isolate algae protein and extrude it into different forms. But while algae may be one of the hottest new protein sources — appearing in products ranging from baked goods to meal replacers — it may have as many strikes against it as positive aspects in its favor.
For one, Crosby said, algae has a stronger flavor than other plant proteins. While the flavor may be loved by some — especially Asian cultures with similar traditional cuisine — it takes others a while to get used to it.
Algae protein is also less nutrient-dense than soy and pea protein. Crosby estimated it has about 30% less protein, meaning more ingredients need to be mixed with it to give it the same dose of nutrients as some of the other options.
Some consumers have also reported digestibility issues with algae protein. In one high-profile case, Soylent blamed consumer reports of gastrointestinal distress on the algal flour in the product and immediately stopped using it — without determining whether the ingredient was the true culprit, according to its algal flour supplier TerraVia Holdings.
Another up-and-coming ingredient, hemp is drawing interest as a good source of protein. However, the ingredient is still picking up steam as something healthy to eat, thanks to its illegal drug cousin marijuana.
While the protein in hemp seeds can be isolated andthe fibrous texture can be used in many applications, it isn’t quite as nutritious as some other plant-based protein options.
“It is lower down the scale in completeness in the essential amino acids,” Crosby said.
On a scale from 0 to 1, if soy protein is a 1 for completeness, hemp is about a 0.5, he added.
Still, hemp protein's advantage is that it's mostly pure. Not much gets added to the protein itself, Crosby said, and its flavor is like soy and pea proteins: Pretty bland and easy to blend in with other ingredients.
Like soy protein, rapeseed protein is a waste product — this time from extracting canola oil. Rapeseed is also used as animal feed, making its use as a plant protein a secondary application.
Rapeseed protein is extremely new to the scene, however.
“Soy oil, vegetable oil, has been produced in this country since the 1920s,” Crosby said. “Whereas canola oil is much much more recent development.”
The oil was developed by Canadian farmers in the 1970s, giving manufacturers and food scientists far less time to wonder about ways to use it. However, Crosby said, rapeseed as an ingredient holds promise — it can be easily extruded like soy and pea protein, and it boasts nutrients that can help in hair and skin development.
“It’s got something going for it as a reason for developing it," Crosby said. "That plus a similar functionality to pea and soy protein.” Crosby said. “It’s being looked at because it's coming from a waste product.”
“Cereal grains offer a lot of protein,” he said.
Old standbys: Oats, barley, wheat and beans
Even though new ways to get protein through plants are being explored, Crosby said that some of the ingredients that have been enjoyed through the centuries are also worth looking at. There’s good reason why grains like oats, barley and wheat and beans of all kinds have been seen as good sources of protein since anyone had understanding of nutrition.
Crosby said about 10% of the world’s protein consumption comes from people eating wheat.
“Cereal grains offer a lot of protein,” he said.