Food fermentations as an essential tool to improve quality and nutritional properties of plant-based protein foods

Plant-based analogues of meat and dairy products can be produced by formulation with plant protein isolates with inclusion of ingredients to achieve the desired texture, color, and flavor. Formulation with refined ingredients, however, contradicts the increasing recognition of the health benefits of a diet that is rich in minimally processed and refined plant foods. Food fermentations are an alternative processing step to obtain high quality plant protein foods with minimally processed ingredients. Fermented foods also contain live microbes to redress the depleted diversity of the gut microbiome in industrialized societies which increases the susceptibility to non-communicable diseases such as inflammatory bowel disease and diabetes. Starter cultures for novel fermented plant protein foods can be selected from the diversity of fermentation microbes that are used in traditional food fermentations. Generally, mycelial molds and bacilli produce hydrolytic enzymes, lactobacilli produce lactic and acetic acids, and yeasts produce volatile flavor compounds. This presentation will describe examples for the selection of starter cultures in novel applications: (i) the use of heterofermentative lactobacilli to control lipid oxidation and thus to eliminate the “beany” off flavor of plant protein preparations; (ii) the use of lactobacilli to reduce the bitter taste of plant foods by deglycosylation of bitter-tasting phytochemicals, (iii) the use of xylanase-producing bacilli as beneficial fermentation microbes in baking to improve bread volume and (iv) the use of protease-producing bacilli to increase proteolysis and the accumulation of taste-active amino acids and peptides in plant-based cheese analogues. In conclusion, fermentation with non-conventional fermentation microbes is likely an essential tool for production of minimally processed and fractionated plant-based protein foods.