Quality of Animal and Plant Proteins Fermented with Pediococcus spp. Strains

Objectives The present paper examines the quality of selected animal and plant proteins that undergo fermentation with Pediococcus acidilactici LUHS29 and P. pentosaceus LUHS183 strains. Materials and Methods Whey protein isolate powder, milk protein concentrate powder, and hemp and lupine seed protein powders were used for 24 and 48-hour fermentation. The analyses conducted included pH, mould/yeast count, total bacteria viable count, lactic acid bacteria viable count, color coordinates, free amino acid profile, gammaaminobutyric acid content, and biogenic amine profile. A Varian ProStar HPLC system (Varian Corp., Palo Alto, California, USA) and Thermo Scientific LCQ Fleet Ion trap mass detector (Thermo Fisher Scientific Inc., Waltham, Massachusetts, USA) were used for chromatographic analysis. Results Fermented plant proteins exhibited a greater viability of lactic acid bacteria and a pH decrease compared to animal proteins. All of the samples were free of yeast and mold. While the fermentation enhanced the redness of the whey, hemp, and lupine proteins, it diminished the lightness in the majority of the milk protein samples. All proteins fermented with the LUHS29 strain had higher levels of free essential and non-essential amino acids, and gamma-aminobutyric acid. Fermented animal proteins contained less gamma-aminobutyric acid and total biogenic amine content than plant proteins. The highest average biogenic amine level (215.8 mg/kg) was found in fermented hemp proteins, whereas the lowest value was found in milk proteins that were fermented with LUHS183 for 48 hours. Conclusions The advantageous aspect of plant proteins in fermentation is highlighted by this study. A considerable increase in free amino acid and gamma-aminobutyric acid content in proteins can be achieved by fermentation with P. acidilactici LUHS29 strain, although particular focus must be paid to the control of biogenic amines production in fermented hemp proteins.