Cristina Castaño

The transition toward clean label, plant-based foods has intensified the search for natural fermentation strategies to reduce off-flavors, while improving taste and nutritional quality of plant proteins. This study evaluated 142 microorganisms isolated from animal-derived ripened foods, selecting four proteolytic Gram-positive cocci (Staphylococcus warneri GC 13 and 28, Rothia uropygioeca GC 15, and Enterococcus lactis GC 40) for fermenting pea protein isolate and textured pea protein as plant-based model substrates. Fermentations at 25 °C for 48 h significantly modified microbiological and physicochemical parameters in a matrix-dependent manner, with textured pea protein supporting higher lactic acid bacteria growth and stronger acidification than pea protein isolate. Free amino acid profiling demonstrated strain- and matrix-dependent proteolytic activity, with GC 13 and 15 promoting the highest total free amino acids in pea protein isolate, while GC 15, 28, and 40 markedly increased multiple amino acids in textured pea protein. Biogenic amine analysis revealed that tyramine was the predominant amine, reaching 162–212 ng/g in inoculated textured pea protein and 348 ng/g in uninoculated controls, whereas only trace levels were detected in the pea protein isolate. Volatile organic compound analysis grouped compounds into three clusters, evidencing a reduction in native beany aldehydes and the formation of alcohols, ketones, and acids, particularly in textured protein, indicating substantial reshaping of the aroma profile. Overall, the results showed that the evaluated strains can be exploited as clean-label tools to enhance proteolysis, attenuate off-flavors, and maintain acceptable biogenic amine levels in pea protein matrices, with R. uropygioeca 15 emerging as a promising candidate for plant protein fermentation.

Traditional dry-cured and fermented foods are part of the diet of many countries all over the world. These products are a source of lactic acid bacteria (LAB). Some of the LAB isolated from these products have a variety of probiotic effects on the consumers, among others, maintaining gastrointestinal homeostasis, enhancing immunity, providing antioxidant effects, preventing vaginal and urinary tract infections, and treating obesity. In addition, LAB has antagonistic properties against human pathogens and foodborne bacteria. This review summarizes methods for isolation, characterization, and selection of LAB with probiotic effects. Besides the effect of the selected probiotic LAB, focusing on gastrointestinal adhesion and colonization, and the described mechanisms of action, emphasizing their potential to advance nutritional innovations, will also be discussed. Furthermore, the advantages of the application of selected probiotic LAB in traditional dry-cured and fermented foods and in plant-based analogues will also be reviewed.

The aim of the study was to use a commonly employed technology in the meat industry, the inoculation of a biocontrol starter, in the processing of a plant-based fermented dry-cured sausage analog to improve its safety against possible Listeria monocytogenes contamination. Challenge tests were used to select suitable lactic acid bacteria (LAB) for the analog under industrial production conditions. First, 20 LAB strains were tested in vitro and five of them were further tested by stuffing the ingredients under industrial conditions. The L. monocytogenes counts highlighted Latilactobacillus sakei 205 as the most protective one, achieving a reduction of 2.6 log CFU/g. Further, a triangular test and Check-All-That-Apply test were performed to understand the organoleptic differences that could be expected in the final product. The batch inoculated with Llb. sakei 205 did not show any sensory differences from the commercial batch. Therefore, Llb. sakei 205 was identified as a potential protective starter due to the microbiological and sensory results. This pioneering study applied biocontrol starters to plant-based meat analogs, aligning with clean-label trends.

The effect of selected autochthonous Lactic Acid Bacteria (LAB) against Listeria monocytogenes was evaluated in two elaborations of soft-ripened cheese performed under high and low relative humidity (RH) elaborations, to achieve a_w ranging from 0.97 to 0.94 in ripened cheeses. Two selected autochthonous strains of Lacticaseibacillus casei 31 and 116 were used. In each elaboration, 8 batches were physicochemically and microbiologically evaluated throughout the ripening process. The a_w and pH decreased during ripening to final values ranging from 0.944 to 0.972 a_w and 5.0 to 5.3 pH, respectively. LAB was the only microbial group that increased throughout the ripening in high and low RH elaborations. In batches that were uninoculated with LAB strains, L. monocytogenes was either maintained at the initial inoculation level or showed a slight reduction by the end of the ripening process. However, in LAB-inoculated batches in the two elaborations, steady decreases of L. monocytogenes were observed throughout maturation. L. casei 31 alone or in combination with strain 116 provoked reductions of 2 to 4 log CFU/g in L. monocytogenes over 60 days of ripening, which could be enough as a strategy for biocontrol to deal with the usual contamination by L. monocytogenes during cheese processing.