EFFECT OF OHMIC HEATING AND LYE-SALT CONCENTRATIONS ON TOTAL SOLUBLE SOLIDS AND TITRABLE ACIDITY OF TOMATO PUREE

S.R. SAWANT¹*, J.P. PANDEY², A. SINGH³, OM PRAKASH^4
1Division of Agricultural Engineering, ICAR-Indian Council of Agricultural Research, New Delhi, Delhi 110001, India
²Department of Post-Harvest Process and Food Engineering, G. B. Pant University of Agriculture and Technology, Pantnagar, 263153, Uttarakhand, India
³Department of Post-Harvest Process and Food Engineering, G. B. Pant University of Agriculture and Technology, Pantnagar, 263153, Uttarakhand, India
⁴Department of Chemistry, G. B. Pant University of Agriculture and Technology, Pantnagar, 263153, Uttarakhand, India
* Corresponding Author : sanketsawant476@gmail.com

Received : 25-02-2019     Accepted : 12-03-2019     Published : 15-03-2019
Volume : 11     Issue : 5       Pages : 8002 - 8006
Int J Agr Sci 11.5 (2019):8002-8006

Keywords : Ohmic heating, Lye and salt concentrations, Field strength, TSS and titrable acidity
Academic Editor : Yadav Dil Raj, Mishra Ved Kumar, Athar H
Conflict of Interest : None declared
Acknowledgements/Funding : Authors are thankful to Department of Post-Harvest Process and Food Engineering, G. B. Pant University of Agriculture and Technology, Pantnagar, 263153, Uttarakhand, India
Author Contribution : All authors equally contributed

The study was initiated with the objective of evaluating the effect of ohmic heating and lye (NaOH, KOH)-salt (NaCl) concentrations on the quality parameters such as total soluble solid (TSS) and titrable acidity of ohmically heated tomato puree. Ohmic heating works on the principle of electroporation due to the resistivity of the product internal heat generated and therefore conversion of electrical energy into heat happened. The parameters such as field strength and lye- salt concentration which were found considerably effect on titrable acidity and total soluble solids. The full factorial statistical design was used to analyze the dependent parameters. The independent variables selected for the study were lye concentrations (0.1, 0.2, 0.3, and 0.4%), salt concentrations (0.1, 0.2, 0.3 and 0.4%) and applied electric field strength (928.57, 1071.42 and 1214.28 V/m). The results of the study show that the acidity values were all within a certain range, approximately 0.43% to 0.31% for 0.1%NaOH at 928.57 V/m and 0.4%NaCl at 1214.28 V/m treatments, best condition of treatment was 0.1% NaOH with 928.57 V/m. Ohmic heating keeps the TSS of tomato puree well within the acceptable range. The optimal values of independent variables in terms of lye or salt and electric field strength for TSS0.3%NaOH/1071.42V/m, 0.3%NaOH/928.57V/m, 0.2%NaOH/1071.42V/m, 0.2%NaOH/928.57V/m, 0.1%NaOH/1071.42, 0.1% NaOH/928.57V/m. It can be concluded that ohmic heating minimize the losses of acidity and TSS of tomato puree. No previous work dealing with the comparison of the impact of ohmic heating processing acidity and TSS of tomato puree has been found therefore this study aims to address this deficiency.

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