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Colour degradation of acidified vegetable juice
Author(s) -
Loong MannNa,
Goh HweeKwang
Publication year - 2004
Publication title -
international journal of food science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.831
H-Index - 96
eISSN - 1365-2621
pISSN - 0950-5423
DOI - 10.1111/j.1365-2621.2004.00802.x
Subject(s) - pasteurization , chemistry , degradation (telecommunications) , food science , kinetics , arrhenius equation , reaction rate constant , activation energy , organic chemistry , physics , quantum mechanics , computer science , telecommunications
Summary Mixed vegetable juice was acidified to a pH below 4 and subjected to pasteurization regimes between 80 and 100 °C. Hunter colour scale values ( L, a and b ) of the pasteurized samples were analysed to determine the kinetics of green and total colour degradation. The ‘ a ’ value was chosen as the physical parameter for green colour while ‘ Lab ’ represented the total colour. A concept, based on fractional conversion, was used for the determination of kinetic parameters. The results revealed that degradation of green and total colour of the acidified vegetable juice followed first‐order kinetics. Temperature dependency of the rate constants for both the green and the total colour could be described by the Arrhenius relationship. The activation energies of green and total colour degradation were 49.19 and 29.00 kJ mol −1 , respectively.