Abstract

                                The present study investigates the development of functional enriched sugarcane juice processed through ohmic heating. Currently, ready to drink functional enriched sugarcane juice with extended shelf life is not available in markets. As conventional heat processing methods reduce the taste, color, and flavor of juices, functional enriched sugarcane juice blended with amla and lemon juice extracts was developed with extended shelf life processed with minimal heat treatment by utilizing ohmic heating - a novel food processing technology. Ohmic Heating (OH) is an alternative thermal treatment as it causes volumetric heating of the sample with a short processing time and it causes minimum discoloration and maintains the nutritive value of the food. The preliminary trials were carried out to optimize the levels of sugarcane juice, amla juice and lemon juice for acceptable sensory attributes on 9 point hedonic scale. Response Surface Methodology (RSM) was used to determine the combinations of the experiment. The independent variables considered were sugarcane juice, amla juice and lemon juice. The responses considered were sensory attributes such as color, flavor, taste and overall acceptability. The optimum levels of sugarcane juice, amla juice and lemon juice were 91.998 mL, 4.720 mL, and 3.282 mL, respectively. The optimum levels were blended for the development of functionally enriched sugarcane juice. The standardized juice was processed using ohmic heating with two different treatments, viz., 50 °C (T1) and 60 °C (T2), for 3 minutes at 25 V/cm. The processed juice was collected in sterile glass bottles and stored at 5 ËšC for conducting storage studies at regular intervals. Microbial and sensory parameters of the untreated, control (pasteurized), and ohmic heated juice were analyzed using one-way analysis of variance (ANOVA). No significant difference (p>0.05) was observed in sensory immediately after ohmic processing when compared to control samples but showed a highly significant difference (p<0.01) in sensory during the storage period. There was a high significant difference (p<0.01) in the total plate count of ohmic heated samples compared to control and during the storage period. No coliform was found in all ohmic heated and control samples. Yeast and mold were present in the untreated sample, but after ohmic heating, no growth was observed. Hence highest microbial reduction was observed in ohmic heating treatment T2 than T1 and control, and the shelf life also extended up to 4 weeks.

Key words : Sugarcane juice; Response surface methodology; Ohmic Heating; Microbial reduction; Shelf life