Application of kefir-isolated Lactiplantibacillus plantarum and Lacticaseibacillus paracasei to obtain a cashew-based fermented beverage with enhanced anti-inflammatory properties

Abstract

The increasing demand for healthy non-conventional probiotic foods has positioned plant-based milk analogues as viable alternatives to traditional dairy products. In these matrices, fermentation with probiotic lactic acid bacteria (LAB) offers the opportunity to develop new functional foods with enhanced sensory, nutritional, and health properties. The present study aimed to develop a functional probiotic beverage by fermenting a cashew-based matrix with LAB isolated from kefir grains, characterizing its techno-functional and anti-inflammatory properties. A cashew-based beverage was prepared and subjected to various heat treatments before fermentation assays. Lacticaseibacillus paracasei CIDCA 8339 and CIDCA 83124, Lactiplantibacillus plantarum CIDCA 8327, and Lactococcus lactis subsp. lactis CIDCA 8221 were evaluated for beverage fermentation at 30°C. All strains achieved high counts (8-9 log CFU/mL), but only CIDCA 8327 and CIDCA 8339 reduced the pH to approximately 5.00-5.20. Notably, L. plantarum CIDCA 8327 demonstrated the ability to inhibit the growth of undesirable spore-forming microorganisms that survive pasteurization. The mixed-culture of CIDCA 8327 and CIDCA 8339 enhanced LAB growth and acidification (pH 4.53 after 24h). This effect occurred with increased lactic and acetic acid production. This resulting fermented beverage exhibited a notably high protein (4.7%), fiber (1.8%), and lipid content (7.8%, with over 75% of unsaturated fatty acids) compared to commercial plant-based fermented beverages. The product exhibited colloidal stability for at least one month during refrigeration and showed a higher apparent viscosity (130.5 mPa.s) than its unfermented counterpart (102 mPa.s). Additionally, the non-microbial fraction from the fermented beverage successfully suppressed the inflammatory response by 85% in a Caco-2-ccl20:luc reporter system, a significant improvement over the 50% reduction seen with the unfermented product. This suggests that LAB produce bioactive metabolites, such as organic acids, which enhance the immunomodulatory effects. In conclusion, the cashew-based matrix is highly suitable for kefir-isolated LAB. However, selecting an appropriate starter culture is crucial for achieving a product with a low spoilage microbial load. In this context, fermentation with the mixed starter CIDCA 8327 and CIDCA 8339 resulted in a nutritious probiotic beverage with enhanced techno-functional characteristics and anti-inflammatory properties, indicating its potential as a functional food to support gastrointestinal health.