Fermentation can boost plant protein digestibility and absorption

MycoTechnology is a Colorado-based company that produces functional ingredients by fermenting them with shiitake mycelia, the filament-like roots of mushrooms that it uses as a natural processing agent. Its products have a wide range of applications, including bitter blockers — helpful for manufacturers to reduce sugar in products such as FermentIQ PTP, a fermented mycelial blend of pea and rice protein.

A PDCAAS ‘perfect score’ of 1.0

A recent animal-based study demonstrated fermentation could improve plant proteins’ nutritional value, bestowing rice and pea protein a PDCAAS of 1.0, similar to that of animal proteins. The results were published in LWT Food Science and Technology.

Developed over 30 years ago by the Food and Agriculture Organization (FAO) and World Health Organization (WHO), the Protein Digestibility Corrected Amino Acid Score (PDCAAS) calculates a protein’s nutritional value by the body’s ability to digest and absorb it, rather than by the amino acid score alone.

In the current study, researchers from MycoTechnology, the University of Illinois and Cornell University conducted ileal digestibility studies. They found that the shiitake-fermented protein delivers a “significantly better” amino acid absorption than the unfermented protein blend. These results may be due to the fermentation process changing the structure of the proteins, making them more digestible. Mycelium may also reduce the presence of anti-nutrient molecules, such as phytic acid, making it harder for the body to absorb the protein.

“This study is a clear indicator that formulators and consumers alike should re-evaluate preconceived notions that animal proteins like whey can nutritionally outperform any plant-based alternative,” said Lisa Wetstone, Senior Director of Strategy and Growth at MycoTechnology.

Valuable for the active nutrition, healthy ageing & fortified nutrition industries

Due to the impractical nature of collecting partially-digested matter from human participants, the current study was carried out on pigs closer in vivo to humans than lab rats. Nevertheless, there are still some important implications for the nutraceutical and functional food industries. For example, manufacturers can source a non-soy plant protein that offers a PDCAAS of 1 for consumers aged three years and over:

“This opens the door to higher quality plant protein products in markets where optimised protein uptake is especially desirable, including the sports, senior, and fortified nutrition sectors,” said MycoTechnology.

 

Wetstone told Vitafoods Insights: “This greater protein absorption increases bioavailability, which means the body can access the benefits of amino acids more readily. A separate unpublished study at the University of Illinois found that initial total amino acid uptake with our plant protein was 30% higher than for standard pea protein and 500% more than for rice protein.”

According to Wetstone, the ability to match the nutritional profile of animal proteins has long been ‘the Achilles heel of plant-based nutraceuticals’, where health benefits are the key driver of purchase, and nutrition-focused consumers scrutinise labels in search of the best nutritional profile available:

“Shiitake mycelium fermentation improves digestibility, nutritional value, flavour and functionality of plant proteins.”