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Kinetic evaluation of color, texture, polyphenols and antioxidant capacity of Irish York cabbage after blanching treatment

School of Food Science and Environmental Health, College of Sciences and Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland
Food Chemistry (Impact Factor: 3.26). 01/2011; 131(1). DOI: 10.1016/j.foodchem.2011.08.032

ABSTRACT In the present work, York cabbage was blanched between 80 to100°C with an increment of 5°C for up to 14 min and kinetics of the different physio-chemical properties were studied. Significant reductions in the texture, color, polyphenols (PPs) and antioxidant (AO) capacity were observed due to blanching. Total phenolic and flavonoid content retained ranged from 19.6-24.5 and 22.0-25.7%, respectively. Heavy losses in the AO capacity also occurred as a result of blanching, which was evident with a loss of 74.0-82.0% in activity as compared to raw York cabbage. Textural studies showed that blanching caused a significant reduction in firmness in the range of 24.0-73.2% and similar trend also observed for color. Kinetic evaluation of degradation was carried out for all the studied quality parameters. The fractional conversion (FC) first-order reaction model showed a good fit for the different studied parameters with the coefficient of determination ranging from 0.892-0.992 except for texture and color, which followed first order and zero order kinetics, respectively. The temperature effect followed the Arrhenius law with activation energy for polyphenolic content, AO capacity, color and texture calculated as 9.22-11.5, 9.05-35.05, 15.73 and 33.8 kJ/mol K, respectively.

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