Milk chocolate matrix as a carrier of novel Lactobacillus acidophilus LDMB-01: Physicochemical analysis, probiotic storage stability and in vitro gastrointestinal digestion

Abstract

Milk chocolate can be formulated with the addition of probiotics. This study was conducted to investigate the physicochemical properties, sensory attributes, and probiotic viability in milk chocolates during storage and in vitro gastrointestinal digestion. Probiotic milk chocolate was prepared by adding the potential probiotic Lactobacillus acidophilus LDMB-01 and stored at 4 and 25 °C for up to 90 days. Control milk chocolate was prepared without probiotics. The stored chocolate samples were analysed for viscosity, pH, water activity, sensory properties, and probiotic viability. The viscosity of probiotic chocolate declined steadily as the storage time progressed, with water activity being slightly increased and pH was unaffected during refrigerated storage up to 90 days. The probiotic cell was found to be viable up to 90 days of storage at 4 °C (>6 log CFU g −1 ) which is sufficient in number to provide potential health benefits to the consumer. As a carrier, chocolate matrix showed a protective effect to the novel probiotics in the gastrointestinal environments compared to free cells. The overall sensory results suggested that the probiotic supplementation had no significant effect on sensory attributes. This study concludes that milk chocolate matrix can potentially be used as a carrier of novel probiotics L. acidophilus LDMB-01 with optimum probiotic viability and unaltered physicochemical properties. • A probiotic milk chocolate was made by adding Lactobacillus acidophilus LDMB-01, a potential novel probiotic, and storing it between 4 and 25 °C for 90 days. • The probiotic cell was proven to be viable after being stored at 4 °C for 90 days (>6 log CFU g −1 ). • An in vitro gastrointestinal digestion experiment showed that chocolate improved probiotic survivability. • The probiotic supplementation had no significant effect on sensory attributes and was widely accepted by the 50-member panel.