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

This study investigated the viability of encapsulated and un-encapsulated (free cell) Lactobacillus rhamnosus GG (LGG) in bread baked at different baking conditions (180 °C for 30 min, 220 °C for 20 min, and 250 °C for 15 min) 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 gave the highest viability (P < 0.05) after subjection to simulated gastric and intestinal juices. The incorporation of LGG did not have significant (P < 0.05) influence on volume, specific volume, moisture, ash, fat, and fiber contents of bread. The lowest moisture content was obtained at baking condition of 180 °C for 30 min, while the highest value was at 250 °C for 15 min. Baking condition did not cause significant (P > 0.05) change in fat, ash, and carbohydrate content of bread. The encapsulation of LGG with multiple layers of encapsulating materials significantly preserved its viability during baking and in simulated gastrointestinal conditions.