Plant-based meats are popular sources of protein for people wishing to avoid eating animal products. What has never been clear is how much of the protein from plant-based meats actually makes it into our cells to nourish them. A recent study suggests that the proteins in imitation meats are not as accessible to cells as the protein found in real meat.

Plant-based meats are made by dehydrating plant foods such as soybeans, black beans, chickpeas or lentils into a powder. Seasonings are added, and the mixture is then heated, moistened and processed through an extruder. The appearance, taste and texture can be manipulated to look like anything from bacon to fish sticks to ground beef. Considered more healthful than animal meats, plant-based meats are high in protein and low in the undesirable fats found in animal foods.

Researchers question how much of the protein from plant-based meats actually gets into the cells of the body.

A bit of chemistry needs to be understood here. Proteins are made up of chains of single amino acids. When eaten, protein is digested into shorter chains of amino acids called peptides, then eventually into single amino acids that the body is able to move into the cells and use.

In lab tests, meat substitutes didn’t break down into peptides as well as the protein in meat does, leading researchers to question how much of the protein from plant-based meats actually enters the cells of the body.

To answer this question, researchers from The Ohio State University wanted to see if body cells could absorb similar amounts of peptides from a meat alternative as they can from a piece of chicken. Using the extrusion process, they created a model imitation meat made from soy and wheat gluten for the experiment.

The meat alternative used in the study had long fibrous pieces that looked like the texture of chicken. Cooked pieces of this meat substitute were ground up and broken down with an enzyme that humans use to digest meat. The same was done with real chicken.

Lab tests on both samples showed that the peptides from the imitation meat were less water-soluble than those from real chicken and not absorbed as well by human cells, leading to concerns about how much protein people absorb when eating imitation meat products.

There may be other ingredients that could be added to plant-based meats to increase imitation meat’s absorption in the human body. The OSU team hopes to look into that possibility next.

The study is published in the Journal of Agricultural and Food Chemistry.