Stability of encapsulated Lactobacillus rhamnosus GG in cocoa (Theobroma cacao L.) juice

Abstract

This study investigated the stability of Lactobacillus rhamnosus GG (LGG) in cocoa juice. Lactobacillus rhamnosus GG was encapsulated separately with sodium alginate and sodium alginate+gum Arabic, and incorporated into cocoa pulp juice. Un-encapsulated LGG (free cell) served as a control. The viability of free and encapsulated LGG in cocoa juice and simulated gastrointestinal conditions was evaluated. The juice was stored at 4 °C for 28 days and its chemical composition was determined weekly. Colour attributes and sensory properties of the freshly prepared juice were also determined. The percentage yield of LGG encapsulated with sodium alginate and sodium alginate+gum Arabic was 80.8 and 89.9%, respectively. Sodium alginate+gum Arabic encapsulated LGG showed higher viability in cocoa juice and simulated gastrointestinal conditions than free cell and LGG encapsulated with sodium alginate only. There was no significant (p>0.05) difference in the pH of cocoa juice that contained sodium alginate only (CJSA) and the one that contained sodium alginate+gum Arabic (CJAG). Titratable acidity of CJAG was significantly (p0.05) difference between CJSA and CJAG in terms of the degree of lightness, however, the samples differed significantly (p0.05) difference between CJFC and CJAG in terms of colour, appearance, aroma, taste, and consistency. This study showed that the encapsulation of LGG with sodium alginate and gum Arabic improved its stability in cocoa juice.

Keywords

• cocoa juice
• encapsulation
• gastrointestinal condition
• lactobacillus rhamnosus gg
• viability