Antioxidant and ACE-Inhibition Activities After In Vitro Digestion of a Non-Fermented Dairy Beverage Enriched with Postbiotics of Lactobacillus spp.

Postbiotics are recently gaining consumer attention for their potential health benefits. This study aimed to examine the effects of supplementation of a non-fermented dairy beverage with postbiotics derived from Lactobacillus acidophilus and Lactobacillus helveticus on antioxidant (DPPH, ABTS, FRAP, and ORAC), antimicrobial, and ACE-inhibition activities before and after in vitro digestion. Three dairy beverages were elaborated: without the addition of postbiotics (T0), with Lactobacillus acidophilus postbiotics (T1), and with Lactobacillus helveticus postbiotics (T2). Before in vitro digestion, T2 presented higher antioxidant activity (p < 0.05). And, after in vitro digestion, except by the ABTS method, T1 and T2 presented the highest antioxidant activities (p < 0.05) and bioaccessibility indexes (p < 0.05). Regarding ACE-inhibition activity, before in vitro digestion, there were no differences among treatments (p > 0.05), but after in vitro digestion, T1 and T2 presented the highest ACE-inhibition activities (p < 0.05) and bioaccessibility indexes (p < 0.05). An antimicrobial effect against Bacillus spp. and S. aureus was observed in Lactobacillus acidophilus and Lactobacillus helveticus postbiotics. However, L. acidophilus postbiotics did not present an antibacterial effect against E. coli. Such findings highlight the potential of postbiotics as functional ingredients to enhance the antioxidant and ACE-inhibition activities of non-fermented dairy beverages, further adding to their appeal as health-promoting dairy food.