Modelling kinetics of thermal degradation of colour in peach puree

• Main Author: Ávila, I.M.L.B.
• Publication Date: 1999
• Other Authors: Silva, C. L. M.
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://hdl.handle.net/10400.14/6454
• topic: Peach puree; Colour degradation; Kinetics; Modelling; Model food

Optimisation of thermal processes relies on adequate degradation kinetic models for food safety and quality. In order to use peach puree as a model food to further validate calculated optimal conditions, isothermal experiments, using peach puree, were performed between 110°C and 135°C. Colour was quantified using the L, a, b system. Two combinations of these parameters, La/b and Total Colour Difference (TCD), were used to evaluate the total colour change. A one-step non-linear regression was performed on all data using the Arrhenius model. The changes in the L and b values followed a first-order reaction with activation energies of 107 ± 7 and 109 ± 8 kJ/mol, respectively. The fractional conversion model was applied to a, La/b and TCD resulting in activation energies of 106 ± 13, 106 ± 10 and 119 ± 9 kJ/mol, respectively.