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 log10 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 °C for 30 sec or 90 °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 log10 CFU/mL), followed by thermal treatment at 76 °C for 30 sec (>7 log10 CFU/mL), and thermal treatment at 90 °C for 60 sec showed the lowest viability (>4 log10 CFU/mL), after 21 days at 4 °C. The pH, titratable acidity and viscosity of all L. acidophilus-tamarind juices demonstrated no changes throughout 21 days at 4 °C. Furthermore, thermal-treated tamarind juice (90 °C for 60 sec) incorporated with L. acidophilus displayed the least change in total soluble solids (1.99 °Brix), while thermal-treated tamarind juice (90 °C for 60 sec) with L. acidophilus and beta-glucans had the lowest color change (∆E = 4.46), after 21 days of storage at 4 °C.@*Conclusion, significance and impact of study@#Thermal treatments (90 °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.

Isolation and characterization of lactic acid bacteria from sugarcane waste

Aims@#Researchers are focusing more on the isolation of new probiotic bacteria to increase varieties for the growing market demand. This study aimed to isolate lactic acid bacteria (LAB) strains from sugarcane waste materials and evaluate its characteristic. @*Methodology and results@#In the present study, two strains of LAB (Isolates A and B) were isolated from sugarcane waste and investigated in vitro for their characteristics as potential probiotics. These isolates were evaluated on their characteristics based on four biochemical tests (acid tolerance, bile tolerance, microbial adhesion, and phenol resistance), with the commercial strain Lactobacillus isolated from Yakult ® served as a positive control. Both isolated strains (>8 log10 CFU/mL) displayed higher survivability than control (>6 log10 CFU/mL) in simulated gastrointestinal conditions at pH 2.0 and pH 6.9 after 24 h. Furthermore, both isolated LABs were resistant to inhibitory substances which are 0.05-0.3% bile and 0.4% phenol. For bile tolerance, isolate A (OD 6.83) had a higher absorbance at 0.3% bile concentration as compared to isolate B (OD 2.20). However, isolate B (7.49 log10 CFU/mL) showed higher resistance towards 0.4% phenol than isolate A (7.11 log10 CFU/mL) after 24 h. Both isolate A and isolate B displayed low cell surface hydrophobicity, strong electron donor, and basic characteristic.@*Conclusion, significance and impact of study@#Both isolates were able to survive under gastrointestinal stress conditions, implying their potential as probiotics. This study demonstrated that valuable products such as probiotic strain could be isolated from sugarcane wastes to use in food production or medical treatment.

Encapsulation of probiotic strain Lactobacillus rhamnosus GG with black bean extract in alginate-pectin microcapsules

Aims@#Probiotics are claimed to confer many health effects upon consumption. However, the survivability of probiotic under the harsh conditions in the gastrointestinal tract has been a challenge. This study aimed to improve the survivability of Lactobacillus rhamnosus GG under gastrointestinal condition through co-extrusion microencapsulation and the addition of black bean extract. @*Methodology and results@#Optimization was carried out on wall material formulation, types of pectin (low and high methoxyl pectin) and alginate: pectin ratio (2:1 and 3:1), and black bean extract concentration (0 to 1% w/v) to produce capsules with desired properties. The effect of L. rhamnosus GG microencapsulation with and without black bean extract on its survivability under simulated gastrointestinal conditions was also investigated. The optimal formulation that gives the highest microencapsulation efficiency (86.17%) was low methoxyl pectin, alginate: pectin ratio at 3:1, and 0.5% (w/v) of black bean extract. The inclusion of black bean extract into L. rhamnosus GG microencapsulation showed no significant effect (p >0.05) on the capsule diameter, with a mean diameter of 715.44 µm and a high microencapsulation efficiency of 97.4%. The viability of encapsulated L. rhamnosus GG increased with black bean extract after 6 h of sequential digestion with the final viable cell count of 12.47 log10 CFU/mL, which meet the minimum requirement of 10

Microencapsulation of Lactobacillus plantarum 299v and its storage in kuini juice

Aims@#Probiotics are living microorganism, when administrated in sufficient quantity can exert beneficial effect to the host. This study focused on the microencapsulation by co-extrusion to increase the viability of Lactobacillus plantarum 299v (Lp299v) in gastrointestinal conditions, and its storage stability in kuini juice at refrigerated (4 °C) and ambient temperature (25 °C). @*Methodology and results@#Lp99v was encapsulated with 1.5% w/v sodium alginate and chitosan coating (0.1% w/v) and yielded a microencapsulation efficiency of 97.71%. The Lp299v microbeads produced were spherical in shape and exhibited a mean microbeads size of 618.75 ± 25.85 µm. Acid and bile tolerance of both free and encapsulated Lp299v were tested in simulated gastric juice (SGJ) for 2 h and in simulated intestinal juice (SIJ) for 4 h, respectively. The encapsulated Lp299v maintained above 108 CFU/mL after exposure to artificial gastrointestinal juice, whereas a significant loss of viability was observed in the free cells. The storage stability of encapsulated Lp299v in kuini juice was determined during 4 weeks of storage at 4 °C and 25 °C. Results showed that encapsulated Lp299v was capable to remain viable (107 CFU/mL) for at least 4 weeks in a refrigerated condition. However, free Lp299v did not survived under both refrigerated and ambient temperature as the storage period extended. @*Conclusion, significance and impact of study@#Lp299v entrapped in chitosan-coated alginate microbeads produced by co-extrusion method is able to enhance the viability of Lp299v above the minimum recommended level in harsh environment (gastrointestinal conditions and low pH of kuini juice).

Microencapsulation of Lactobacillus plantarum 299v incorporated with oligofructose in chitosan coated-alginate beads and its storage stability in ambarella juice

Aims@#Microencapsulation has been used to protect the viability of probiotics in harsh environments such as gastrointestinal conditions and food composition. The present study aimed to optimize the microencapsulation of Lactobacillus plantarum 299v (Lp299v) using co-extrusion by varying two parameters (calcium chloride (CaCl2) and oligofructose (FOS) concentrations) and storage stability of the beads produced in ambarella juice at refrigerated and room temperature. @*Methodology and results@#Chitosan coated-alginate microcapsule prepared with 4.0% (w/v) FOS and 2.5% (w/v) CaCl2 showed highest microencapsulation efficiency (93%). The microcapsules were subjected to gastrointestinal treatment and storage test in ambarella juice. Both encapsulated Lp299v with and without FOS showed higher viabilities compared with free cells after incubated in simulated gastric juice (SGJ) and simulated intestinal juice (SIJ). After 5 h of incubation in SIJ, the viabilities of both encapsulated probiotic with and without FOS were more than 107 CFU/mL. The Lp299v were stored in ambarella juice under refrigerated (4 °C) and room temperature (25 °C) for 4 weeks. At 25 °C, all forms of Lp299v lost their viabilities after one week. On the other hand, at 4 °C, viable cells count of both encapsulated Lp299v with and without FOS were reported to be more than 107 CFU/mL after 4 weeks of storage. @*Conclusion, significance and impact of study@#Microencapsulation with FOS was able to improve Lp299v’s viability during storage in low pH fruit juices compared to those without FOS. The microencapsulated probiotics could be applied in ambarella juice for the development of functional food.