Effect of Ohmic Heating and Lye-Salt Concentrations on Quality Characteristics of Tomato Puree

Objectives: To study the effect of ohmic heating and lye-salt concentrations on quality characteristics of tomato puree. The quality characteristics of tomato puree by using ohmic heating and lye-salt concentrations were investigated. Ohmic heating is also termed as ‘resistance heating or electro heating’ in which an alternating electric current is passed through a food, and electric resistance of the food causes the power to be translated directly into heat. Electroporation has been regarded as the main mechanism of ohmic heating.

Study Design: Full factorial design.

Place and Duration of Study: Department of Post-Harvest Process and Food Engineering and department of Chemistry, GBPUAT, Pantnagar (UK), India, between September 2016 and April 2017.

Methodology: Tomato fruit has remarkable concentration of vitamin E, vitamin A, folate, vitamin C and vitamin A as leading source. The quality characteristics of final product were evaluated in terms of β–Carotene, vitamin A (retinol) and vitamin C (ascorbic acid) of tomato puree.

Results and Conclusion: The value of β–Carotene was observed ranking first in salt (NaCl) solution followed by KOH and NaOH lye solutions for all experimented concentrations. Therefore it reveals that as the temperature of puree increases it resulted increase in β–Carotene which has been computed as vitamin A. The percentage range of retention of ascorbic acid was observed ranking first in NaOH solution (86.01-91.35%) followed by KOH (61.91-77.06%) and Nacl (34.64-56.12%) for all experimented concentrations. It reveals that as the temperature of puree increases it resulted decrease in ascorbic acid which has been computed as vitamin C. No previous work dealing with the comparison of the impact of ohmic heating processing on bioactive components of tomato products has been found therefore this study aims to address this deficiency.