Examine finds low dietary high quality in vegetarian meat

The supply of meals based mostly on plant proteins to substitute for meat has elevated dramatically as extra individuals select a plant-based weight-reduction plan. On the identical time, there are numerous challenges concerning the dietary worth of those merchandise. A examine from Chalmers now reveals that lots of the meat substitutes offered in Sweden declare a excessive content material of iron—however in a type that can not be absorbed by the physique.

The analysis is printed within the journal Vitamins.

A weight-reduction plan largely made up of plant-based meals corresponding to root greens, pulses, fruit and greens typically has a low local weather impression and can also be related to well being advantages corresponding to a diminished threat of age-related diabetes and heart problems, as has been proven in a number of giant research. However there have been far fewer research of how individuals’s well being is affected by consuming merchandise based mostly on what are referred to as textured plant proteins.

Within the new examine from Chalmers, a analysis workforce within the Division of Meals and Diet Science analyzed 44 totally different meat substitutes offered in Sweden. The merchandise are primarily manufactured from soy and pea protein, but additionally embody the fermented soy product tempeh and mycoproteins, that’s, proteins from fungi.

“Amongst these merchandise, we noticed a large variation in dietary content material and the way sustainable they are often from a well being perspective. Usually, the estimated absorption of iron and zinc from the merchandise was extraordinarily low. It is because these meat substitutes contained excessive ranges of phytates, antinutrients that inhibit the absorption of minerals within the physique,” says Cecilia Mayer Labba, the examine’s lead writer, who just lately defended her thesis on the dietary limitations of switching from animal protein to plant-based protein.

The physique misses out on crucial minerals

Phytates are discovered naturally in beans and cereals—they accumulate when proteins are extracted to be used in meat substitutes. Within the gastrointestinal tract, the place mineral absorption takes place, phytates type insoluble compounds with important dietary minerals, particularly non-heme iron (iron present in plant meals) and zinc, which signifies that they can’t be absorbed within the gut.

“Each iron and zinc additionally accumulate in protein extraction. For this reason excessive ranges are listed among the many product’s components, however the minerals are sure to phytates and can’t be absorbed and utilized by the physique,” says Cecilia Mayer Labba.

Iron deficiency amongst girls is a widespread, international downside. In Europe, 10–32% of ladies of childbearing age are affected and nearly one in three teenage women at secondary faculty in Sweden. Girls are additionally the group in society probably to have switched to a plant-based weight-reduction plan and to eat the least quantity of purple meat, which is the principle supply of iron that may be simply absorbed within the digestive tract.

“It’s clear that in the case of minerals in meat substitutes, the quantity that’s obtainable for absorption by the physique is an important consideration. You can’t simply take a look at the record of components. A number of the merchandise we studied are fortified with iron however it’s nonetheless inhibited by phytates. We consider that making vitamin claims on solely these vitamins that may be absorbed by the physique may create incentives for the trade to enhance these merchandise,” says Ann-Sofie Sandberg, Professor of Meals and Diet Science at Chalmers and co-author of the examine.

The meals trade wants new strategies

Tempeh, produced from fermented soybeans, differed from the opposite meat substitutes within the quantity of iron obtainable for absorption by the physique. This was anticipated, because the fermentation of tempeh makes use of microorganisms that break down phytates. Mycoproteins stood out for his or her excessive zinc content material, with out containing any identified absorption inhibitors. Nonetheless, in accordance with the researchers, it’s nonetheless unclear how nicely our intestines can break down the cell partitions of mycoprotein how this in flip impacts the absorption of vitamins.

“Plant-based meals is vital for the transition to sustainable meals manufacturing, and there may be big improvement potential for plant-based meat substitutes. The trade wants to consider the dietary worth of those merchandise and to make the most of and optimize identified course of methods corresponding to fermentation, but additionally develop new strategies to extend the absorption of assorted vital vitamins,” says Cecilia Mayer Labba.

Manufacturing of plant proteins

Most current plant-based protein merchandise available on the market are based mostly on protein extracted from a cultivated plant, corresponding to soybeans, and separated from the plant’s different parts. The protein is then subjected to excessive strain and temperature, which restructures the proteins, referred to as texturization, so {that a} product might be achieved that’s meatier and chewier together with different components.

Chalmers’ examine reveals that the dietary worth of meat substitutes obtainable at present is commonly poor relying on the selection of uncooked materials (typically imported soy) and processing circumstances (content material of anti-nutrients), and on components (fats high quality and salt). A meal containing 150 grams of meat substitutes contributes as much as 60% of the utmost really useful day by day consumption of salt, which in accordance with the Nordic Diet Suggestions is 6 grams.