Viability of Lactobacillus rhamnosus GG in Simulated Gastrointestinal Conditions and After Baking White Pan Bread at Different Temperature and Time Regimes.

Abstract

This study investigated theviability of encapsulated and un-encapsulated (free cell) Lactobacillus rhamnosus GG (LGG) in bread baked at different baking conditions (180°C for 30min, 220°C for 20min, and 250°C for 15min) and in simulated gastrointestinal conditions. The cell was encapsulated either with sodium alginate, singly or in combination with chitosan, cassava starch, and hi-maize resistant starch. There was complete loss of viability of un-encapsulated LGG after baking. Significantly (P < 0.05) higher viability was recorded for LGG encapsulated with sodium alginate + cassava starch + chitosan beads (SCCB) and sodium alginate + hi-maize resistant starch + chitosan beads (SHCB) compared to sodium alginate beads (SAB) and sodium alginate + cassava starch beads (SSB). Lactobacillus rhamnosus GG encapsulated with SHCB gavethe highest viability (P < 0.05) after subjection to simulated gastric and intestinal juices. Theincorporation of LGG did not have significant (P < 0.05) influence on volume, specific volume, moisture, ash, fat, and fiber contents of bread. The lowestmoisture content was obtained at baking condition of 180°C for 30min, while thehighest value was at 250°C for 15min. Baking condition did not cause significant (P > 0.05) change in fat, ash, and carbohydrate content of bread. Theencapsulation of LGG with multiple layers of encapsulating materials significantly preserved its viability during baking and in simulatedgastrointestinal conditions.