Exploring lactic acid bacteria fermentation parameters to produce legume based cheese alternatives. Investigating probiotic potential, nutrient quality, aroma development and in-vitro protein digestibility

Abstract

A novel legume-derived base material with potential as a cheese alternative was developed utilizing three different plant-based sources, yellow pea protein concentrate (yellow PPC), dried Zaiga Variety Peas (Pisum sativum L.), and dried white beans (Phaseolus vulgaris.) all sourced from Latvia. A Lactic acid bacteria (LAB) mesophilic starter culture was added to pasteurized legume solutions to invoke fermentation. The study investigated the following quality parameters; bacterial growth, total dietary fiber (TDF), and free amino acid changes, development of aroma compounds, and the extent of proteolysis through an enzymatic in-vitro digestion model (IVDM) at various processing stages.All substrates supported LAB growth, resulting in a decrease in pH. The highest bacterial load was observed in yellow PPC substrates at 15% w/w concentration and 30°C incubation, measuring 9.84 log CFU/ml indicating possible probiotic benefits. Despite variations in TDF content among the raw legume substrates, fermentation did not significantly alter overall TDF levels. All FAAs (Free Amino Acids) assessed exhibited considerable decline across all substrates, arginine and isoleucine were most utilized; more than 90% in all samples. Acetic acid and ethanol were the predominant volatile compounds detected in all yellow PPC samples, with other aromatic compounds resembling those found in dairy cheese also present. Protein digestibility varied between 80% and 87% across all fermented substrates, showing a tendency of enhanced digestibility following thermal treatment and fermentation for all fermentation factors in the study.Using legume based materials to replace cheese through fermentation with LAB commercial starter culture shows potential. The study observed significant microbial growth in the yellow PPC substrates, indicating possible probiotic benefits. While there were differences in substrate composition, the overall dietary fiber content did not change significantly between before and after fermentation. However, there was a noticeable reduction in free amino acids, suggesting their utilization during the process. Aroma analysis revealed compounds like those found in dairy cheese, highlighting the possibility of sensory similarities of the legume based product. Additionally, protein digestibility improved following fermentation and thermal treatment. These results collectively highlight the possibility of using legumes as an alternative to cheese with potential health and sensory advantages.