Plant-based sources don't always complete the protein puzzle
Editor's Note: This article is part of a series on plant proteins. All stories in this series can be found here.
Protein-enhanced products have become one of the biggest food crazes of the year, with manufacturers adding the macronutrient to everything from cold brew coffee to ice cream and breakfast cereals.
But do consumers and producers understand the steps that need to be taken to make protein-based products actually bioactive?
Some analysts are doubtful.
"In conversation and with marketing and consumer messaging, what gets lost is the quality of the protein message," Cathy Kapica, certified food scientist and CEO of The Awegrin Institute, told Food Dive.
Manufacturers should be concerned about the legitimacy and nutritional relevance of their protein-based products, both to serve their consumers well and to remain competitive with other brands in the same space. That starts with knowing what complete proteins really are, and how they can help — or hurt — consumer diets.
What is a complete protein?
In describing complete proteins, Kapica distinguished between two classes of amino acids, the building blocks of proteins: nonessential and essential. The body requires essential amino acids for several key functions, such as building muscle. Without all of its essential amino acids, a protein is incomplete and cannot offer the nutrients needed to perform those bodily functions.
Products with incomplete proteins can be especially problematic when they are given to growing children.
"If you would switch out cow's milk for almond milk, which has virtually no protein, it's a misnomer to actually call it milk," Kapica said. "You're not getting protein, (but) much less you're not getting a complete protein. For kids who are growing, you're missing out on a huge nutrient source."
When manufacturers are deciding whether they want to use animal or plant-based proteins in their formulas, they need to consider the quality of the protein, Kapica said. Animal-based proteins are generally complete, as is soy.
With plants, things are more complicated.
Chris Davis, senior director of R&D at Impossible Foods, told Food Dive that while plant proteins as a class might be complete, the seed proteins of grasses, such as rice, wheat and corn, often don't have the amino acids needed to create a complete protein.
Davis explained that wheat, which lacks the amino acid lysine, could be combined with other plant proteins that contain lysine, such those in pulses.
"That's kind of the drawback to that," Kapica said. "You can use these plant-based proteins, which are cheaper, but if you want the complete protein, you may have to pay extra to include these amino acids separately."
Ultimately, manufacturers should consider that consumers can best achieve a healthy diet and adequate complete protein consumption by eating combinations of different foods, Davis said. That's one reason why beans and rice are such a popular protein powerhouse combination: They balance each other by providing the proteins that the other lacks.
"Humans need to eat a balanced diet that supplies all the amino acids required to support healthy metabolism and growth, which is best achieved by eating a wide variety of foods," said Davis. "Certain protein sources such as soy, beans and green vegetables have close to the ideal balance of amino acids."
"Generally proteins and amino acids are fairly stable through heating manufacturing," Davis continued. "But once again, the question is, are they going to interact with something else in that formulation? You may have mineral solidification. Is somehow that amino acid going to bind with the mineral and make the both of them less bio-available?"
Why does having a complete protein matter to manufacturers?
The most important reason manufacturers need to ensure protein-based products actually contain what the body needs is to substantiate product label claims. Producers often have strict rules when it comes to labeling foods as a "good source of" nutrients, and protein should be no different.
When making protein-related label claims, its crucial for manufacturers to partner with food scientists to determine whether their assertions are scientifically backed and whether their ingredients suppliers are legitimate.
Producers should also be aware that the addition of amino acids or any ingredients to compete a protein could generate concerns from consumers looking strictly for clean labels.
"Because you want to make label claims, you want to have a clean label. There's so many parts of that," said Kapica. "To be able to do this, it has to come down to working with that food science person who can basically say, 'This is your best source for this application if you're going to include these other ingredients'."
How can manufacturers create compliant complete proteins?
If a protein itself is not complete, manufacturers have a few different options. One is to add another source that contains the missing amino acids — preferably from commodity crops that cost less than specialty ingredients.
"Protein combinations formed from commodity crops will always be more affordable than those created using niche crop plants," said Davis. "However, some of the grass seed proteins are low in the amino acid lysine, so supplementation is an option."
Davis offers another alternative for manufacturers looking to keep costs down while exploring the benefits of complete proteins, strictly through the production methods implemented.
"It is possible to supplement by addition of lysine as the free amino acid, which is produced by fermentation, rather than as a component of a different protein."
Regardless how a manufacturer decides to attempt offering additional protein through its product, as long as the company abides by label claim best practices and aims for complete proteins, success should follow.