The Effects of Pasteurization by Conventional and Ohmic Heating Methods and Concentration Processes on the Madan (Garcinia Schomburgkiana Pierre) Juice Properties

Abstract

HighlightsThis research proved that Madan juice should be filtered before pasteurization in order to be more palatable for consumer.Madan juices and its concentrates can be efficiently heated by ohmic method due to their high electrical conductivities.Mathematical models developed in this study can accurately predict the electrical conductivity of the Madan juice during ohmic heating.This research proved that the quality of pasteurized Madan juice concentrates was rather steady during 60 days of storage.Abstract.Madan is a native fruit of the Southeast Asian region. The objectives of this research were: 1) to investigate the effect of pasteurization methods on the qualities of Madan juices and 2) to examine the influence of ohmic heating on the qualities and storage stability of pasteurized and concentrated juice compared to conventional heating method. It appeared that Madan juices (5-27.2 °Brix) can be heated by ohmic method due to high electrical conductivities (1.37-4.74 S.m-1). Mathematical models developed in this study can precisely predict the electrical conductivity of Madan juice. Filtration step and pasteurization condition of 95°C for 15 s should be applied in Madan juice processing because they provided the highest sensorial scores and the lowest color change. The continuous-mode machine provided the lightest color with low redness and yellowness values. Quality changes of Madan juice concentrate samples pasteurized using double jacket kettle and ohmic heating method were diminutive during 60 days of storage. Keywords: Concentration, Juice, Madan, Ohmic heating, Pasteurization.