In Vitro Digestion of Vacuum-Impregnated Yam Bean Snacks: Pediococcus acidilactici Viability and Mango Seed Polyphenol Bioaccessibility

This study investigates the in vitro digestion of vacuum-impregnated <i>yam bean</i> snacks enriched with <i>Pediococcus acidilactici</i> and mango seed polyphenols, focusing on bacterial survival and polyphenol bioaccessibility. The snacks were prepared by vacuum impregnation (VI) with solutions containing either mango seed extract, <i>P. acidilactici</i>, or a combination of both, followed by dehydration. The antimicrobial activity of the treatments was assessed against pathogens, revealing limited effectiveness, likely due to insufficient concentrations of mango seed extract and the intrinsic resistance of the bacteria. VI of mango seed extract improved the total soluble phenols (TSP) content up to 400% and maintained the initial probiotic concentration (10⁶ cell/mL). In vitro digestion was performed to simulate gastrointestinal conditions, measuring the stability of TSP and the survival of <i>P. acidilactici.</i> The results indicated that the viability of <i>P. acidilactici</i> fluctuated throughout the digestion process (10⁶ to 10⁴ log UFC/g), the polyphenols showed varying degrees of bioaccessibility (11 to 30%), and the TSP content in the intestinal fraction ranged from 1.95 to 6.54 mg GAE/g. The study highlights the potential of VI for incorporating functional components into plant-based snacks, though further optimization is necessary to enhance the stability of <i>P. acidilactici</i> and the effectiveness of the bioactive ingredients.