Mathematical modeling and optimisation of sugarcane juice level in grape beverage using response surface methodology (RSM)

The vegetative clarified sugarcane juice (SCJ) was used as sugar replacer in the preparation of beverage. The specific proportions of sugarcane juice were utilized for beverage preparation using central composite rotatable design (CCRD). Response surface analysis for grape beverages indicated that sensory flavor and overall acceptability (OAA) scores varied from 6.04 to 8.10 and 6.72 to 7.95, respectively on nine point hedonic scale. The differences in the sensory scores for respective attributes were highly significant (P<0.01). The beverage containing 4% sugar and 40% SCJ resulted in 16° Brix and 47 TSS-acid ratios, which were the best in terms of their flavor and overall acceptability. Sensory data were regressed against sugarcane juice (x) and sugar (x_j) for second order polynomial models, which were found to be adequate as coefficient of multiple determinants (R²) was more than 80%, calculated F-ratio more than that of the F-table value and insignificant lack of fit test. Multiple response optimizations resulted in the best combinations of sugarcane juice and sugar as 43.6% and 4.38%, respectively. Subsequent evaluations on storage for 90 days at 37°C reduced sensory scores from 7.55 to 7.15. Ready-to-serve beverages prepared from optimized recipe gave products of microbiologically safe and sterile nature. Their storage for 90 days at 37°C reduced sensory scores Sugarcane juice could be used as replacer of sugar in the preparation of sugarcane juice based beverage.