Glucose, fructose and sucrose content in broccoli, white cabbage and Portuguese cabbage grown in early and late seasons

Abstract

Consumption of Portuguese cabbage and white cabbage is very high in Portugal, but diets including broccoli have been highly recommended owing to recognition of the health-protective effects of secondary plant metabolites. Broccoli production is generally concentrated in the summer/winter season, but the demand for a fresh product throughout the year requires production in other seasons. Sugars might affect¯avour and the acceptance of broccoli by consumers. This study reports the free fructose, glucose and sucrose content in primary and secondary in¯orescences of 11 cultivars of broccoli, one white cabbage and four Portuguese cabbages grown in early (March±July) and late (August±January) seasons in the northern region of Portugal. On average the results show that the total free sugar content in the broccoli cultivars, except for cv Marathon, is signi®cantly (P < 0.05) lower than in the other cabbages. Fructose was the major sugar in the three types of Brassica, representing between 48.8 and 56.9% of the total sugar content in broccoli cvs Marathon and Senshi respectively and between 48.7% (cv Mirandela) and 53.8% (cv Murciana) in the other cabbages. Glucose was the second major sugar, while sucrose represented a maximum of 20.5% in broccoli cv Shogun and 11.1% in cv Murciana. The growing season in¯uenced the free sugar content, with generally higher levels in the spring/summer than in the summer/winter season in broccoli, while an opposite tendency was noted in the other Brassica species. In broccoli the sugar levels in the primary in¯orescences were generally lower than in the secondary in¯orescences, except for sucrose. # 2001 Society of Chemical IndustryKeywords: sucrose; fructose; glucose; free sugars; broccoli; white cabbage; Portuguese cabbage; growing season INTRODUCTIONBrassicaceous plants represent one of the major vegetable crops grown worldwide. Portuguese cabbage (Brassica oleracea L var tronchuda Bailey syn var costata de Candolle) and white cabbage (B oleracea L var capitata L) are the major cabbages consumed in Portugal, 1 but broccoli (B oleracea L var italica Plenck) consumption has been increasing owing to its potential to protect against several types of cancer.2 The quality of these and other vegetables might be in¯uenced by the climatic conditions, which affect the synthesis of primary and secondary plant compounds.3 Broccoli is usually grown in the summer/winter season, but the demand for a fresh product throughout the year requires the crop to be grown in other seasons such as spring/summer, in which above-optimum temperatures for growth are likely to affect composition.Soluble sugars are the primary compounds of metabolism which are transported or stored temporarily, providing energy and the C skeletons for the synthesis of other compounds. They play an important

Kinetic studies for the preparation of probiotic cabbage juice: Impact on phytochemicals and bioactivity

“…Glucose was the main sugar present, accounting for ≈55% of the total sugar while fructose accounted for almost 45%. This result is in line with previous findings, demonstrating that glucose and fructose are the main sugars present in white cabbage (Rosa et al, 2001). It is worth remarking that the sugar content reduced continuously as the bacterial population increased throughout the fermentation time.…”

Genotypic effects on glucosinolates and sensory properties of broccoli and cauliflower

“…This corresponds to the literature, which show a slightly higher fructose or glucose proportion depending on cultivation period and place [35,[43][44][45]. The sucrose proportion was low with 5 up to 8% in green, purple and Chinese broccoli as well as in purple cauliflower.…”

Triangle tests indicate that irrigation timing affects fresh cabbage sensory quality

“…Although the cultural requirements to maximize production of head cabbage (Brassica oleracea Capita Group) are well documented (Wien & Wurr, 1997), the effects of field management on cabbage sensory characteristics are less known. Variety, plant spacing and planting date are reported to affect a wide range of organic compounds associated with cabbage flavor (MacLeod & Nussbaum, 1977;Rosa, David, & Gomes, 2001;Van Etten, Daxenichler, Williams, & Kwolek, 1976). Some production factors may also play a role in human perception of cabbage quality.…”