Viability of the probiotic Lactobacillus plantarum microencapsulated in skim milk and maltodextrin: Implications for nutritional and functional uses

Abstract

Probiotic lactic acid bacteria provide numerous physiological benefits, but their viability is often compromised during processing, storage, and gastrointestinal transit. This necessitates innovative techniques to preserve their functionality and enhance their nutritional contribution. This study evaluates the viability of microencapsulated Lactobacillus plantarum isolated from North Sumatra River buffalo milk. Probiotics were encapsulated using skim milk and maltodextrin as carriers, followed by spray drying. The viability of microencapsulated and free cells of L. plantarum was tested under simulated gastrointestinal conditions and during storage at 4 ºC and room temperature for 30 days. Subsequently, the data were analyzed using ANOVA, revealing that skim milk and maltodextrin significantly enhanced probiotic survival, with retention rates of 92.19% (8.79 log CFU/g) and 90.53% (8.61 log CFU/g), respectively. Microencapsulated L. plantarum exhibited lower population reductions than free cells under simulated gastric (pH 2) and bile salt conditions, maintaining populations of 7.69 log CFU/g and 7.43 log CFU/g, respectively. After 30 days, viable counts remained at 10⁷ CFU/g at 4 °C and 10⁵ CFU/g at room temperature. These findings indicate that microencapsulation with skim milk and maltodextrin effectively protects L. plantarum, preserving its potential as a functional probiotic.