Vegetable proteins are in high demand
due to current issues surrounding
meat consumption and changes in eating habits, but they are still
not accepted by consumers due to their strong bitterness, astringent
taste, and “beany” off-flavor. This review aimed to
give an overview of the “beany” off-flavor and the potential
of microorganisms to decrease it. Twenty-six volatile compounds were
identified from the literature as contributing to the “beany”
off-flavor, and their formation pathways were identified in a legume
matrix, pea. Biotechnological ways to improve the flavor by reducing
these volatile compounds were then looked over. As aldehydes and ketones
are the main type of compounds directly linked to the “beany”
off-flavor, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase
(ALDH) were focused on. By converting aldehyde and ketones into alcohols
or carboxylic acids, these two enzymes have the potential to decrease
the off-flavor. The presence of the two enzymes in a selection of
microorganisms (Lactobacillus acidophilus, Limosilactobacillus fermentum, Lactiplantibacillus
plantarum, Streptococcus thermophilus, Saccharomyces cerevisiae, and Gluconobacter suboxydans) was done with a catabolism and a bioinformatical study. Finally,
the correlation between the presence of the enzyme and the efficacy
to improve the flavor was investigated by comparison with the literature.
The presence of ADH and/or ALDH in the strain metabolism seems linked
to an odor improvement. Especially, a constitutive enzyme (ADH or
ALDH) in the catabolism should give better results, showing that some
fermentative types are more inclined to better the flavor. Obligatory
fermentative strains, with a constitutive ADH, or acetic acid bacteria,
with constitutive ADH and ALDH, show the best results and should be
favored to reduce the amount of compounds involved in the “beany”
off-flavor and diminish that off-flavor in legume proteins.