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.
ABSTRACT
A novel method for the synthesis of nanocrystalline zinc oxide without any additive was developed using zinc acetate and 1,4-butanediol through sonication. The structure and morphology of prepared nanocrystalline zinc oxide was investigated by various techniques like TEM, XRD, EDAX, UV-Vis spectroscopy. The solvent 1,4-butanediol played a dual role of fuel as well as capping agent eliminating addition of any extraneous species. The results showed that using ultrasound sonication is green, cost effective compared to conventional wet chemical method for ZnO nanoparticle synthesis.
