Effect of thermal treatments on the storage stability of Lactobacillus acidophilus La-14 tamarind juice with or without beta-glucans

Aims: This study aimed to evaluate the effect of thermal treatment on the storage stability of Lactobacillus acidophilus La-14 tamarind juice with or without beta-glucans. Methodology and results: Lactobacillus acidophilus incorporated with 6% (w/v) beta-glucans displayed the highest viability (17.28 log(10) CFU/mL) as compared to other beta-glucans concentrations (0-8% w/v). The L. acidophilus with or without beta-glucans survived more than 80% after 5 h of sequential digestion. Tamarind juice was subjected to different thermal treatments (76 degrees C for 30 sec or 90 degrees C for 60 sec) and incorporated with L. acidophilus with or without betaglucans. Lactobacillus acidophilus in tamarind juice without thermal treatment showed the highest viability (8.69 log(10) CFU/mL), followed by thermal treatment at 76 degrees C for 30 sec (>7 log(10) CFU/mL), and thermal treatment at 90 degrees C for 60 sec showed the lowest viability (>4 log(10) CFU/mL), after 21 days at 4 degrees C. The pH, titratable acidity and viscosity of all L. acidophilus-tamarind juices demonstrated no changes throughout 21 days at 4 degrees C. Furthermore, thermal-treated tamarind juice (90 degrees C for 60 sec) incorporated with L. acidophilus displayed the least change in total soluble solids (1.99 degrees Brix), while thermal-treated tamarind juice (90 degrees C for 60 sec) with L. acidophilus and beta-glucans had the lowest color change (Delta E = 4.46), after 21 days of storage at 4 degrees C. Conclusion, significance and impact of study: Thermal treatments (90 degrees C for 60 sec) had contributed to the stability of L. acidophilus-tamarind juice with beta-glucans over 21 days of cold storage. This study shows thermal treated tamarind juice with L. acidophilus and beta-glucans is a potential functional non-dairy beverage catered for lactose intolerance individuals.