Effect of storage time on ascorbic acid and total phenolic contents and colour of blanched, boiled and steamed cauliflowers (Brassica oleracea L. ssp. botrytis)

The effect of storage time on ascorbic acid content (AAC), total phenolic content (TPC) and colour of blanched, boiled and steamed cauliflowers (Brassica oleracea L. ssp. botrytis) was investigated. Blanching and steaming retained more AAC in cauliflower as compared to boiling. Storage time showed no significant changes in AAC measured at 30 min interval up to 2.5 h in all samples with the expection of boiled sample at 2.5 h in which significant reduction was observed. Blanching resulted in a higher TPC in cauliflower as compared to boiling or steaming. There were no significant differences between the TPC of boiled and steamed cauliflowers. Storage time showed no significant changes in TPC measured at 30 min interval up to 2.5 h in all samples. As for the colour measurement, there were significant reduction in the L*, a* and b* values of the blanched, boiled and steamed cauliflowers as compared to raw cauliflower but there were no significant changes in these colour values measured at 30 min interval up to 2.5 h. This study demonstrated that blanched, boiled or steamed cauliflower can be stored up to 2 h with no significant changes in the AAC, TPC, L*, a* and b* colour values.