Fermenting fruit juices with lactic acid bacteria (LAB) is a sustainable method to enhance fruit harvests and extend shelf life. This study focused on blackberries, rich in antioxidants with proven health benefits. In this research, we examined the effects of fermentation (48 h at 37 °C) at 28 days on whey-supplemented (WH, 1:1) blackberry juice (BJ) inoculated with two LAB mixtures. Consortium 1 (BJWH/C1) included Levilactobacillus brevis, Lactiplantibacillus plantarum, and Pediococcus acidilactici, while consortium 2 (BJWH/C2) comprised Lacticaseibacillus casei and Lacticaseibacillus rhamnosus. All of the strains were previously isolated from aguamiel, pulque, and fermented milk. Throughout fermentation and storage, several parameters were evaluated, including pH, lactic acid production, viscosity, stability, reducing sugars, color, total phenolic content, anthocyanins, and antioxidant capacity. Both consortia showed a significant increase in LAB count (29–38%) after 16 h. Sample BJWH/C2 demonstrated the best kinetic characteristics, with high regression coefficients (R² = 0.97), indicating a strong relationship between lactic acid, pH, and fermentation/storage time. Despite some fluctuations during storage, the minimum LAB count remained at 9.8 log CFU/mL, and lactic acid content increased by 95%, with good storage stability. Notably, sample BJWH/C2 increased the total phenolic content during storage. These findings suggest that adding whey enhances biomass and preserves physicochemical properties during storage.

This study investigates the potential of blackberry juice fortified with whey as a carrier for transporting and protecting lactic acid bacteria (LAB). The interactions between whey proteins and the juice were examined to assess their impact on probiotic stability and protection during storage and passage through the gastrointestinal tract. Additionally, the study explored how this combination influences the antioxidant properties of the product. The results indicated that the blackberry juice and whey protein mixture provided moderate protection to Lacticaseibacillus rhamnosus GG compared to the positive control (inulin), suggesting that whey proteins may enhance probiotic viability. Proteolytic analysis revealed progressive protein hydrolysis during fermentation, leading to the release of bioactive peptides, indicating the formation of compounds with potential functional benefits. Moreover, samples inoculated with LAB exhibited higher antioxidant activity than those without inoculum. This research demonstrates the promise of fermented blackberry juice fortified with whey proteins as an effective probiotic delivery system. It opens new possibilities for developing functional foods to promote intestinal health and overall well-being.

The food industry has a strong interest in lactic acid bacteria (LAB) because of their probiotic potential and health advantages. LAB have been previously isolated from pulque and agave sap, showing antibacterial action. However, their reaction to stress can limit their survivability, and their biological activities are strain-specific. To ascertain the impact of LAB isolated from pulque and agave sap on lifespan, thermal and oxidative stress, and health span parameters, we fed the nematode Caenorhabditis elegans these bacteria. The nematodes fed the Escherichia coli OP50 strain were utilized as a control for each experiment. Animals were fed each strain for four days starting from L4 and either (day 5) exposed to oxidative stress caused by high hydrogen peroxide concentrations (8 mM) or acute heat stress (35 °C) for four hours. The strains Lacticaseibacillus rhamnosus and Lactiplantibacillus plantarum significantly improved lifespan, fertility, movement, and heat shock resistance. Lacticaseibacillus casei enhanced the C. elegans lifespan, and Levilactobacillus brevis only increased its survivability in the heat shock studies. Interestingly, we discovered a harmful impact on animals fed Pediococcus acidilactici. This study highlights that, even when strains come from the same plant source, their biological activity might differ significantly.