Statistical optimization of blanching time and temperature of Irish York Cabbage using the desirability function

The effect of different heat treatments, as a means of preprocessing, on the phytochemicals present in Irish York cabbage was studied. A comparison of blanching (by immersing in water) and microwaving (using water as a medium) indicated that microwaving is detrimental to the phytochemicals present in cabbage. To achieve a blanching time and temperature combination that would result in minimal loss of phytochemicals, central composite design that integrates a desirability approach was used. A second-order polynomial equation was developed, indicating the effect of the blanching time and temperature on the total phenol content (TPC), total flavonoid content (TFC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) values. Contour maps generated using the response surface equation showed that the experimental variables significantly affected the response. The optimized factors (85C and 2min) were used for blanching York cabbage to obtain a TPC, TFC and half maximal effective concentration for DPPH of 31.01mg gallic acid equivalents/g, 21.2mg quercetin equivalents/g and 0.93mg/mL, respectively. PRACTICAL APPLICATIONS: Processing of cabbage is generally carried out before it can be developed into a product. The present study used statistical software to obtain the time and temperature conditions for preprocessing of cabbage. The statistical software helped in achieving conditions wherein minimal loss of phytochemicals took place. The application of the software for optimizing the conditions helped in cutting down the amount of time and resources for identifying optimum value of different factors.