Degradation of colour in beetroot (Beta vulgaris L.): a kinetics study

• Published in: Journal of food science and technology Vol. 51; no. 10; pp. 2678 - 2684
• Main Authors: Chandran, Janu, Nisha, P., Singhal, Rekha S., Pandit, Anirudha B.
• Format: Journal Article
• Language: English
• Published: India Springer India 01.10.2014; Springer Nature B.V
• Subjects: Cereals; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Cooking; Food; Food quality; Food Science; Gas flow; Heat; Heating; Isothermal processes; Kinetics; Mathematical models; Nutrition; Original; Original Article; Pigments; Studies; Temperature; Vegetables; India; Beetroot; EcoCooker; Colour degradation; Betalin; Quality kinetics; Rate constant
• DOI: 10.1007/s13197-012-0741-9
• ISSN: 0022-1155

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.