Taro (Colocasia esculenta) extract fermented by a probiotic co-culture as a wall material for microencapsulation of Lactiplantibacillus plantarum and functional food development

Abstract

Functional foods offer health benefits beyond basic nutrition, driving interest in products with multiple functional properties. This study developed and optimized a non-dairy taro extract fermented by the co-culture of Lactiplantibacillus plantarum CCMA 0743 and Pichia kluyveri CCMA 0615, followed by spray drying. The process, optimized by Response Surface Methodology, resulted in a powder with high cell recovery efficiency (90.74 % for L. plantarum and 47.76 % for P. kluyveri), drying yield above 55 %, low water activity (0.38), low hygroscopicity (<5 g/100 g), and solubility >70 %. Fermentation reduced glucose by 65 % and completely depleted mannose, while significantly increasing lactic acid (10.64 ± 0.19 g/100 g), citric, and malic acids, and reducing oxalic acid by 68 %, an antinutrient. The fermented extract also showed higher total phenolic content and antioxidant activity, consistent with microbial metabolism during fermentation, which released bioactive compounds. Volatile profile analysis revealed a reduction in off-flavors (1-octen-3-ol) and an enrichment in bioactive and sensorially desirable compounds, such as phenylethanol, benzyl alcohol, and hexanoic and octanoic acids, thereby enhancing aromatic complexity. During 180 days of refrigerated storage, L. plantarum remained above 108 CFU/g and exhibited high survival in simulated gastrointestinal digestion (>106 CFU/mL), whereas P. kluyveri declined rapidly but contributed to postbiotic and aromatic metabolites. Overall, the fermented taro extract demonstrated promising characteristics as a synbiotic and multifunctional ingredient, combining probiotic viability, prebiotic starch retention, postbiotic metabolite production, and physicochemical and sensory stability, supporting its application in plant-based products and functional supplements.