The viability of encapsulated lactobacillus plantarum during cupcake baking process, storage, and simulated gastric digestion

Abstract

In this study, the Lactobacillus plantarum viability in the cupcake according to baking time was investigated for the first time. L. plantarum was microencapsulated by the emulsion method in κ-carrageenan mixed with skim milk (CS sample) or carrageenan coated by skim milk (CcS sample). The average size, and the L. plantarum viability during cupcake baking, cold storage and in the simulated intestinal fluid (SGF) were investigated. The result showed that the particle size was 165μm and 320μm for the CS and CcS samples respectively. In the cupcake baking process indicated that the L. plantarum viability in control samples was decreased 0.21; 0.66; 2.13; and 5.33 log CFU/cake after 2; 4; 8; and 12 min baking respectively as compared to the initial, whereas the decreasing of the L. plantarum viability was 0.22 to 0.34; 0.80 to 0.90; 1.48 to 1.50; and 3.58 to 3.80 log CFU/cake in CS samples and CcS samples respectively. The pH value of the control samples was 6.8 to 6.5 which tended to be lower than the microencapsulated samples during 14 days of storage, though there was not a significant difference. Additionally, the L. plantarum viability in the control, CS and CcS samples was tended to increase slightly during storage. However, L. plantarum cells showed high sensitivity with the SGF medium. The longer the storage time, the more sensitive L. plantarum in SGF. The CcS sample showed significant higher protective efficacy in SGF than the CS samples. The same result was not observed in simulated intestinal fluid. In the sensory test, the difference between the cupcake with and without the addition of microcapsules was not significant.