Kaushik Khamrui

Enhancement of survival of alginate-encapsulated Lactobacillus casei NCDC 298.

BACKGROUND Micro-encapsulation of hydrocolloids improves the survival of sensitive probiotic bacteria in the harsh conditions that prevail in foods and during gastrointestinal passage by segregating them from environments. Incorporation of additives in encapsulating hydrocolloids and coatings of microcapsules further improves the survival of the probiotics. In this study, the effect of incorporation of resistant-maize starch in alginate for micro-encapsulation and coating of microcapsules with poly-l-lysine, stearic acid and bees wax on the survival of encapsulated Lactobacillus casei NCDC 298 at pH 1.5, 2% high bile salt, 65 °C for 20 min and release of viable lactobacilli cells from the capsule matrix in simulated aqueous solutions of colonic pH were assessed. RESULTS Addition of resistant maize starch (2%) improved the survival of encapsulated L. casei NCDC 298. Coating of microcapsules with poly-L-lysine did not further improve the protection of encapsulated cells from the harsh conditions; however, bees wax and stearic acid (2%) improved the survival under similar conditions. Incorporation of maize starch (2%) in alginate followed by coating of beads with stearic acid (2%) led to better protection and complete release of entrapped lactobacilli in simulated colonic pH solution was observed. CONCLUSION Additional treatments improve the survival of alginate-encapsulated lactobacilli cells without hindering the release of active cells from the capsule matrix and hence, the resulting encapsulated probiotics can be exploited in the development of probiotic functional foods with better survival of sensitive probiotic organisms.

Optimisation of ingredients for a low‐fat, Chhana‐based dairy spread using response surface methodology

The effect of ingredients, viz. chhana, skimmed milk powder (SMP), maltodextrin and whey powder, on sensory and texture responses of a low-fat chhana-based spreads was studied and its formulation was optimised using response surface methodology. In linear and quadratic terms, chhana and SMP significantly influenced all the responses. The interaction term between maltodextrin and chhana was the most effective in influencing texture parameters. Optimisation suggested 55.6% chhana, 6.2% SMP, 4% maltodextrin, 2% whey powder, 1.5% edible salt, 1.5% enzyme-modified cheese, 0.5% sodium tripolyphosphate, 0.5% trisodium citrate, 0.3% glycerol monostearate and 28% water with desirability of 0.889, as the best levels of these ingredients in a formulation that also contained 1.5% edible salt, 1.5% enzyme-modi ed cheese, 0.5% sodium tripolyphosphate, 0.5% trisodium citrate, 0.3% glycerol monostearate and 28% water on a w/w basis.

Instrumental texture profile of reduced-calorie Peda as a function of ingredients using response surface methodology

Response surface methodology in a five-level, four-factor central composite rotatable design (CCRD) was used to model the instrumental texture profile of reduced-calorie Peda as a function of the sugar and fat replacers; sucralose, whey protein concentrate (WPC), maltodextrin and sorbitol. The relevant quadratic regression models for various responses revealed that all the textural parameters could be accurately predicted by these four factors. Among the ingredients, in linear, quadratic and interaction terms, sorbitol was involved the maximum number of times in significantly influencing the texture profile parameters, followed by WPC, sucralose and maltodextrin, respectively.