title: Degradation of colour in beetroot (Beta vulgaris L.): a kinetics study.
abstract: The kinetics of colour (measured as Hunter 'a/b' value) degradation in beetroot puree (Beta vulgaris L.) was studied over a temperature range of 50-120 °C (isothermal process), and also during normal open pan cooking, pressure-cooking and a newly developed and patented fuel-efficient 'EcoCooker' (non-isothermal heating process). The degradation of visual colour as measured as Hunter 'a/b' value was found to follow a first order kinetics, where the rate constant increased with an increase in the temperature. The temperature dependence of degradation was adequately modeled by Arrhenius equation. A mathematical model has been developed using the kinetic parameters obtained from the isothermal experiments to predict the losses of color in the non-isothermal heating/processing method based on the time-temperature data for each of the methods. The results obtained indicate a colour degradation of similar magnitude in all the three modes of cooking used in the study.
authors.affiliation: Agro-Processing and Natural Products Division, National Institute for Interdisciplinary Science and Technology (NIIST), CSIR, Thiruvananthapuram, 695019 Kerala India.
authors.forename: Janu
authors.initials: J
authors.lastname: Chandran
authors.affiliation: Agro-Processing and Natural Products Division, National Institute for Interdisciplinary Science and Technology (NIIST), CSIR, Thiruvananthapuram, 695019 Kerala India.
authors.forename: P
authors.initials: P
authors.lastname: Nisha
authors.affiliation: Department of Food Engineering and Technology, Institute of Chemical Technology, University of Mumbai, Matunga, Mumbai, 400 019 India.
authors.forename: Rekha S
authors.initials: RS
authors.lastname: Singhal
authors.affiliation: Chemical Engineering Department, Institute of Chemical Technology, University of Mumbai, Matunga, Mumbai, 400 019 India.
authors.forename: Anirudha B
authors.initials: AB
authors.lastname: Pandit
keywords: Beetroot; Betalin; Colour degradation; EcoCooker; Quality kinetics; Rate constant