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Title
Abstract
Broccoli (Brassica oleracea L. var. italica) contains numerous biologically active compounds. However, their levels change during processing and storage. The objective of the research study was to determine the effect of short-term storage (1 ÷ 4 days) of broccoli heads at different temperatures (3 ºC, 16 ºC, and 21 ºC) on the contents of phenolic acids, selected flavonoids (quercetin and kaempferol), and tocopherols. Broccoli heads were harvested in autumn when they reached their maximum size and their buds were 2 mm in diameter. The content of phenolics and tocopherols depended on the storage time of broccoli heads. The lowest content of phenolics was found immediately after the broccoli was harvested, whereas the highest content thereof was reported after 4 days of storage. However, the storage temperature did not impact the contents of those compounds. In the research study, the content of caffeic acid was reported to be highest in the fresh broccoli heads; the content of sinapic acid was the second-highest, and that of the ferulic acid was the third-highest. The content of kaempferol in the broccoli heads was higher than that of quercetin. No differences were reported in the content of quercetin and kaempferol at particular storage temperatures on every single day of the experiment. An increase was reported only when compared with the control sample (the 0 day of storage). In the broccoli heads, the predominant tocopherol was α-tocopherol. The lowest loss in the total tocopherols occurred while storing at a temperature of 3 ºC and the highest: at a temperature of 21 ºC.
Keywords
Brassica oleracea L. var. italica, HPLC, phenolics, tocopherols, storage, temperature