Probiotication of Tomato and Carrot Juices for Shelf-life Enhancement using Micro-encapsulation

ABSTRACT: This study was aimed at probiotication of tomato and carrot juices using Lactobacillus plantarum, Lb. fermentum, Lb. casei, Lysinibacillus sphaericus and Saccharomyces boulardii. To enhance the stability, the probiotic cultures were micro-encapsulated using alginate coated chitosan beads. Tomato and carrot juice samples were pasteurized for 20 min at 63 °C. Lb. fermentum, Lb. plantaram, Lb. casei and Lysinibacillus sphaericus, Saccharomyces boulardii were inoculated and incubated at 37 °C for a period of 72 h. After the probiotication the pH decreased from6.8to 4.5 and correspondingly increased the titratable acidity from 0.12 to 0.36% during the period. Among the probiotic strains the viable cell count were increased from 6.5 to 8.9 log CFU/mL in Lysinibacillus sphaericus and5.2 to 7.6 log CFU/mLin Saccharomyces boulardii, during 24 to42 h and later it decreased slowly.Viability of encapsulated cells were higher than free cells in tomato and carrot juices stored at 4 °C over a period of 5 - 6 weeks indicating better cell protection in the former. However, the addition of probiotic beads influenced the sensory quality of the product by increasing the swallowing difficulty and remaining particles of the encapsulated ones increased the turbidity of vegetable juices.