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ThesisItem Open Access Study on Ohmic heating characteristics of tomato peeling(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-06) Ramnath, Sawant Sanket; Pandey, J.P.Peeling is one of the important unit operations in the tomato industry to ensure good final product quality because the consumer increasingly demands better quality products. Current industrial methods of tomato peeling are hot water and steam peeling, both of which suffer from various disadvantages; caustic, high pH waste with the former, and excessive water use with the latter. In this study, ohmic peeling was attempted to potentially address these problems The studies on ohmic heating characteristics of tomato peeling were undertaken with the objective of investigating the behavior of ohmically heated tomato puree in terms of quality parameters at different field strengths, lye and salt concentrations. The independent variables selected for the study were field strengths (1214.28, 1071.42 and 928.57 V/m), lye concentrations (0.1, 0.2, 0.3 and 0.4 %) and salt concentrations (0.1, 0.2, 0.3 and 0.4%). The peeling performance and quality characteristics of final product were evaluated in terms of percentage of peeling ease of peeling, vitamin A, vitamin C, acidity and total soluble solid. Results indicated that in terms of quality of peeling, the best conditions of ohmic heating peeling were 0.3% NaOH at 1214.28 V/m and 0.3% NaCl at 1214.28 V/m. The experimental conditions showed the potential to be satisfactory for processing because they required a reasonably short time (approximately 1 min). Further, the potential to preheat the media to 60 ÂșC or more with reusable media could further shorten the peeling time. The results also showed that lye concentrations (NaOH and KOH), field strengths (1214.28, 1071.42 and 92857 V/m) and salt concentrations (NaCl) had significantly effect on percentage of peeling, ease of peeling, vitamin A, vitamin C, acidity and TSS. The results of processing parameters indicates that the best conditions of field strengths, lye and salt concentrations for vitamin A and - carotene are 0.3 % NaOH at 1214.28 V/m and 0.3 % NaCl at 1214.28 V/m respectively, for vitamin C 0.1% NaOH at 928.57 V/m, for acidity 0.1% NaOH at 928.57 V/m and for TSS 0.3% NaOH at 1071.42 v/m, Peeling losses were significantly lower in tomatoes treated with ohmic heating compared to hot water. In conclusion, ohmic heating may be a promising alternative to hot water and steam for tomato peeling and its technological advancement in the tomatoprocessing industry.