The effect of cooking and processing on the glucosinolate content: Studies on four varieties of portuguese cabbage and hybrid white cabbage

The concentrations of individual and total glucosinolates were measured in four types of Portuguese cabbage and in one hybrid white cabbage before and after cooking. Typical Portuguese culinary procedures include boiling the cabbage for 10 min but for particular kale types the leaves are first shredded then boiled for 5 min (Caldo verde). Analysis of the fresh cabbage, cooked leaves and cooking water showed that the glucosinolate content of the cabbages is reduced by more than 50%. Almost all of this loss is accounted for as intact glucosinolates in the cooking water, normally used for soups in Portugal.     

Changes in Glucosinolate Concentrations in BrassicaCrops (BoleraceaandBnapus) Throughout Growing Seasons

In the Iberian Peninsula, Brassica crops are grown throughout the year and may be consumed at immature stages or leaves may be harvested by ‘picking-over’ during plant growth. Consumption of Brassicas in Portugal is high but there is no information on the levels of glucosinolates in such material. Changes in the total and individual glucosinolate concentrations of four Brassica oleracea types (two cultivars of Portuguese cabbage, one Portuguese kale type and one hybrid white cabbage) and one Portuguese Brassica napus type were monitored throughout two growing seasons, spring/summer (SS) and summer/winter (SW). Glucosinolates were determined between sowing and maturity corresponding to nine sampling dates in the leaves and five harvests in the heads. The main glucosinolates in B oleracea types were 3-methylsulphinylpropyl-, allyl- and indol-3-ylmethyl- whereas in the B napus type pent-4-enyl-, 2-hydroxybut-3-enyl- and but-3-enylglucosinolate predominated. In the leaves of B oleracea types, the highest concentration of total glucosinolates and of most of the individual glucosinolates was observed at 14 days after sowing whilst, in the heads the highest levels were noted at the start of head formation. In the B napus , the highest total and individual glucosinolate concentration was generally observed at the end of the growing season. Both for the total and for the main individual glucosinolates there were significant differences ( P< 0·001) between the nine harvest dates and between growing seasons. Between the two seasons, the glucosinolate levels in SS were generally higher than in SW. A comparison of cultivars showed the hybrid cabbage to have generally higher glucosinolate levels than the Portuguese types, except for B napus .     

Influence of Fermentation Conditions on Glucosinolates, Ascorbigen, and Ascorbic Acid Content in White Cabbage (Brassica oleracea var. capitata cv. Taler) Cultivated in Different Seasons

ABSTRACT:  The content of glucosinolates (GLS), ascorbigen, and ascorbic acid in white cabbage ( Brassica oleracea var. capitata cv. Taler) cultivated in different seasons (summer and winter) was determined, before and after spontaneous and starter-induced fermentation. Different salt concentrations (0.5% NaCl or 1.5% NaCl) were used for sauerkraut production. Glucoiberin, sinigrin, and glucobrassicin were dominating in raw white cabbage cultivated either in winter or summer seasons. Ascorbigen precursor, glucobrassicin, was found higher in cabbage cultivated in winter (2.54 μmol/g dw) than those grown in summer (1.83 μmol/g dw). Cabbage fermented for 7 d was found to contain only traces of some GLS irrespective of the fermentation conditions used. Ascorbigen synthesis occurred during white cabbage fermentation. Brining cabbage at low salt concentration (0.5% NaCl) improved ascorbigen content in sauerkraut after 7 d of fermentation at 25 °C. The highest ascorbigen concentration was observed in low-sodium (0.5% NaCl) sauerkraut produced from cabbage cultivated in winter submitted to either natural (109.0 μmol/100 g dw) or starter-induced fermentation (108.3 and 104.6 μmol/100 g dw in cabbages fermented by L. plantarum and L. mesenteroides , respectively). Ascorbic acid content was found higher in cabbage cultivated in summer and fermentation process led to significant reductions. Therefore, the selection of cabbages with high glucobrassicin content and the production of low-sodium sauerkrauts may provide enhanced health benefits towards prevention of chronic diseases.     

Myrosinase activity and total glucosinolate content of cruciferous vegetables,and some properties of cabbage myrosinase in Taiwan

The myrosinase activity and total glucosinolates of 10 different cruciferous vegetables and some properties of cabbage (Brassica oleracea L var capitata L) myrosinase were investigated. Radish, cabbage and broccoli showed higher myrosinase activity than other samples. No correlation (P > 0–05) was found between myrosinase activity and total glucosinolates of cruciferous vegetables tested. Myrosinase activity for white cabbage was higher than red cabbage. An optimal pH of myrosinase activity was observed at pH 8–0 for both white and red cabbages. The myrosinase extracted from cabbage was more stable in neutral or alkaline pH. The optimal temperature of myrosinase activity for both cabbages was about 60°C, but the myrosinase activity was destroyed after heating at 70°C for 30 min. The myrosinase activities of both white and red cabbages were activated by 10 mM and 5 mM ascorbic acid, respectively.     

Free amino acid composition in primary and secondary inflorescences of 11 broccoli (Brassica oleracea var italica) cultivars and its variation between growing seasons

Eleven broccoli cultivars were grown in the field in spring/summer (April–July) and summer/winter (September–January). Free amino acid composition was determined by HPLC in primary and secondary inflorescences separately. A total of 17 amino acids were identified: L ‐alanine (Ala), L ‐arginine (Arg), L ‐asparagine (Asn), L ‐aspartic acid (Asp), glycine (Gly), L ‐glutamic acid (Glu), L ‐glutamine (Gln), L ‐histidine (His), L ‐isoleucine (Ile), L ‐leucine (Leu), L ‐methionine (Met), L ‐phenylalanine (Phe), L ‐serine (Ser), L ‐threonine (Thr), L ‐tryptophan (Trp), L ‐tyrosine (Tyr) and L ‐valine (Val). The major amino acid was L ‐glutamine, which represented on average between 39.5% (in cvs Durango and Green Valiant) and 55.5% (in cv Shogun) of the total amino acid content among cultivars, followed by L ‐glutamic acid with a variation between 12.1% (in cv Shogun) and 17.4% (in cv Marathon). A few amino acids represented less than 1% each (Gly, Leu, Met, Phen, Thr, Trp and Tyr). For most of the amino acids there were significant differences between cultivars, whilst only a few amino acids showed significant variations between inflorescences. Season also induced significant differences in the content of most of the identified amino acids. The cultivar with the highest total free amino acid content (323.9 mmol kg⁻¹ DW) on average of both seasons (391.3 in spring/summer and 256.4 in summer/winter) was Shogun, whilst the others were above the minimum of 177.3 mmol kg⁻¹ DW found in cv SK3. There was a general tendency for higher total amino acids levels in spring/summer than in summer/winter, but it was clear that this effect was dependent on the cultivar. © 2000 Society of Chemical Industry     

Comparison of glucosinolate levels in commercial broccoli and red cabbage from conventional and ecological farming

Broccoli heads and red cabbage of both conventional and ecological origin were purchased from the market at monthly intervals over a 1-year period. After freeze-drying of the samples the glucosinolates were extracted, enzymatically desulphated and analyzed by HPLC-UV. Glucoraphanin, glucobrassicin and neo-glucobrassicin turned out to be the predominant glucosinolates in broccoli. Red cabbage contained similar amounts of glucoraphanin and glucobrassicin but, in addition, appreciable amounts of glucoiberin, progoitrin, sinigrin, gluconapin and glucoerucin, while neo-glucobrassicin occurred at trace levels only. No significance was found comparing the contents of glucoraphanin in the two cultivation groups for either broccoli or red cabbage. Organic broccoli and red cabbage both contained significantly higher amounts of glucobrassicin than their conventionally grown counterparts. Conventional crops of red cabbage yielded significantly higher quantities of gluconapin than ecological crops. Broccoli imported from Spain and Italy during the winter months yielded levels of glucosinolates similar to those of the home-grown products available in summer and autumn.

Evaluation of pesticide residue dynamics in Chinese cabbage,head cabbage and cauliflower

ABSTRACT

Pesticide residues from the time of application until harvest were analysed for 20, 17 and 18 active insecticidal and fungicidal substances in Chinese cabbage, head cabbage and cauliflower, respectively. In total, 40 mathematical models of residue degradation were developed using a first-order kinetic equation, and from these models it was possible to forecast the action pre-harvest interval for a given action threshold for low-residue production in Brassica vegetables as a percentage of the maximum residue level. Additionally, it was possible to establish an action pre-harvest interval based on an action threshold of 0.01 mg kg^?1 for the production of Brassica vegetables for baby food. Among the evaluated commodities, the speed of residue degradation was highest in head cabbage, medium in Chinese cabbage and lowest in cauliflower. The half-lives of pesticide in various vegetables were also determined: they ranged from 1.55 to 5.25 days in Chinese cabbage, from 0.47 to 6.54 days in head cabbage and from 1.88 to 7.22 days in cauliflower.     

Quality parameters of Brassica spp. grown in northwest Spain

The edible portions of different Brassica spp. grown in several areas of Northwest Spain (Galicia) were studied during 2007 and 2008. The aim of the study was to determine and compare the values of some physicochemical parameters (moisture, soluble solids, titratable acidity, pH, protein, ash, vitamin C, total phenolics, chlorogenic acid, caffeic acid, p‐coumaric acid, quercitin and chlorophyll) in different edible portions of turnip greens and turnip tops (Brassica rapa var. rapa), Galega kales (B. oleracea L. var. acephala), white cabbages (B. oleracea L. convar. capitata var. alba) and Savoy cabbage (B. oleracea L. convar. capitata var. sabauda). Different values were obtained for the parameters depending on the variety of plant. In general, the nutrient contents of the turnips and the Galega kales were higher than those of the cabbages. Variations within different edible portions were also observed. Moreover, the mean values of the parameters measured in leaves were higher than those measured in stems, except for moisture content. High concentrations of soluble solids, protein, vitamin C and phenolics were found in the different varieties of Brassica studied.     

Phenolic compound contents in edible parts of broccoli inflorescences after domestic cooking

Total flavonoid and individual hydroxycinnamoyl derivative (sinapic and caffeoyl‐quinic acid derivative) contents were evaluated in the edible portions of freshly harvested broccoli (cv Marathon inflorescences) before and after cooking and in the cooking water. High‐pressure boiling, low‐pressure boiling (conventional), steaming and microwaving were the four domestic cooking processes used in this work. The predominant sinapic acid derivatives were identified as 1,2,2′‐trisinapoylgentiobiose and 1,2′‐disinapoyl‐2‐feruloylgentiobiose. In addition 1,2‐diferuloylgentiobiose and 1‐sinapoyl‐2,2′‐diferuloylgentiobiose were also identified in broccoli inflorescences. The results showed large differences among the four treatments in their influence on flavonoid and hydroxycinnamoyl derivative contents in broccoli. Clear disadvantages were detected when broccoli was microwaved, namely high losses of flavonoids (97%), sinapic acid derivatives (74%) and caffeoyl‐quinic acid derivatives (87%). Conventional boiling led to a significant loss of flavonoids (66%) from fresh raw broccoli, while high‐pressure boiling caused considerable leaching (47%) of caffeoyl‐quinic acid derivatives into the cooking water. On the other hand, steaming had minimal effects, in terms of loss, on both flavonoid and hydroxycinnamoyl derivative contents. Therefore we can conclude that a greater quantity of phenolic compounds will be provided by consumption of steamed broccoli as compared with broccoli prepared by other cooking processes. Copyright © 2003 Society of Chemical Industry     

Improvement of Fermented Chinese Cabbage Characteristics by Selected Starter Cultures

Traditional fermented vegetables have inconsistent quality and high nitrite content, whereas a commercial starter culture could overcome these problems. A total of 34 lactic acid bacteria strains were screened from 2 homemade naturally fermented Chinese cabbages. Fermented characters of single starter or mixed cultures were examined, including acidification, growth rate, and nitrite depletion ability in the fermented culture. As a result, the combined starter culture (Lactobacillus delbrueckii IWQ and Lactobacillus paracasei J21) was selected. The fermented Chinese cabbage resulted from this mixed starter culture had higher sugar content residue (30.5 mg/mL for mixed culture and 22 mg/mL for control). And the titratable acid of the cabbage fermented by the mixed starter was 110°T, which was twice higher than that of control sample. The selected starter culture also had a better texture and sensory qualities than that the starter cultures from a local fermented Chinese cabbage plant, especially for its significantly lower nitrite content (3.00 mg/kg for mixed culture and 4.49 mg/kg for control). The findings of this study form a database for further studies on the development of starter cultures for fermented cabbage production and could replaced the local plant starter culture.     

Variation in the content of glucosinolates,hydroxycinnamic acids,carotenoids, total antioxidant capacity and low‐molecular‐weight carbohydrates in Brassica vegetables

Bioactive compounds were investigated in genotypes (cauliflower 10, white cabbage 10, curly kale 1) and plant parts of the three crops. The content of most of the major glucosinolates glucobrassicin, sinigrin and glucoiberin differed significantly between cultivars. Samples harvested in 2000 had higher amounts of several glucosinolates than samples from 1999. Within cauliflower the buds of the floret had 1.5 to 2.5‐fold higher concentration of glucobrassicin and 4‐methoxyglucobrassicin than the stalk. In white cabbage several glucosinolates had their highest content in the outer leaves (up to 2‐fold higher). Upper leaves of curly kale contained 5‐fold more of total glucosinolates than lower leaves. Chlorogenic acid was the dominating hydroxycinnamate in curly kale, which also contained at least ten times more of carotenoids (mainly lutein) than white cabbage. Total antioxidant capacity (TAC) assayed with the FRAP method was 0.76 (0.06) µmol/g fw (mean (SD)) in water‐soluble and 0.32 (0.04) in water‐insoluble extracts of cauliflower which was 62–68% higher than in white cabbage. Curly kale contained 6.4 and 6.1 µmol/g fw TAC in water‐soluble and water‐insoluble extracts. TAC did not differ between plant parts. Progoitrin and 4‐hydroxyglucobrassicin were correlated to water‐soluble TAC in white cabbage, probably reflecting a variation in other compounds. Cauliflower contained less glucose, fructose and sorbitol but more sucrose than white cabbage. Curly kale had lower contents of glucose (～2 times), fructose (～4–5 times) and sucrose (20 and 36 times, respectively) than cauliflower and white cabbage, while inositol was only found in curly kale. Storage of white cabbage reduced the amount of sorbitol and sucrose. The study shows that cultivar, plant part and storage affect the content of bioactive compounds in Brassica vegetables. The variation between years, as in cauliflower, is due to environmental factors. Since the cultivar ranking order was rather stable for several components the data could provide a basis for the selection of cultivars optimised for valuable health components for fresh market consumption. Copyright © 2005 Society of Chemical Industry     

1‐MCP does not improve the shelf‐life of Chinese cabbage

Chinese cabbages cv ‘Yuki’ (Brassica campestris L ssp pekinensis (Lour) Olsson) were treated with air containing 1‐methylcyclopropene (1‐MCP) at concentrations ranging from 0 to 1 µl l^?1 for 12 h at 22°C before storage for 9 weeks at 3°C. Quality, weight loss and trimming loss were measured before treatment, and before and after storage, but were not influenced by 1‐MCP. 1‐MCP at 0.1 and 1.0 µl l^?1 elicited increased levels of respiration and ethylene production which subsided when the cabbages were placed in cold storage. Copyright © 2004 Society of Chemical Industry     

添加紫甘蓝粉、花椰菜粉、麦胚粉对曲奇中丙烯酰胺生成的影响

目的 探究添加紫甘蓝粉、花椰菜粉、麦胚粉对曲奇中丙烯酰胺生成的影响,为优化焙烤食品配方、控制丙烯酰胺生成提供基础。方法 参考AACC方法,分别以一定比例的植物粉替代等量面粉制作曲奇,以未添加植物粉曲奇为对照,采用HPLC-MS/MS法测定曲奇中丙烯酰胺的含量。结果 三种植物粉对丙烯酰胺生成的影响不同。在添加量为1%~10%时,添加紫甘蓝粉、花椰菜粉的曲奇中丙烯酰胺含量随添加量增加而增大。添加量为10%时,丙烯酰胺含量分别为对照的26.25、68.52倍,而添加麦胚粉曲奇则影响不显著。结论 添加紫甘蓝粉、花椰菜粉和麦胚粉对曲奇中丙烯酰胺的生成有不同影响。     

The effects of cultivar and physiological age on quality and shelf-life of coleslaw mix packaged in modified atmospheres

Two cultivars of ‘Dutch’ cabbage were used to determine conditions whereby coleslaw made from them could be stored under modified atmospheres (MA) with minimal deterioration. The cabbage was sliced and mixed (4:1) with shredded carrot. The effects of storing the cabbages prior to processing, the cultivar identity, and use of low temperatures and MA storage on the quality and storage life were investigated. Quality in terms of appearance and aroma were measured as well as bacterial contamination before and during storage. Cultivar (cv.) Marathon rather than cv. Lennox gave a product of higher quality, with a better shelf‐life, particularly when packaged under micro‐perforated PA‐160 film rather than oriented polypropylene (OPP). Long‐term storage of cabbage prior to processing had detrimental effects on the acceptability of MA packaged coleslaw. Attempts were made to explain the findings in terms of differences in microbial counts. Guidelines were established that could be used in the production of high quality coleslaw mix packaged in MA.     

不同贮藏条件下白菜中亚硝酸盐含量的研究

以室温、冰箱、添加不同量（0g／100mL、2g／100mL、4g/100mL、6g／100mL、8g/100mL）绵白糖发酵为贮藏条件,研究不同贮藏条件、不同时间下,白菜中亚硝酸盐含量的变化,探究适宜贮藏条件。结果表明：室温、冰箱贮藏条件下,白菜中亚硝酸盐含量始终低于ADI值,相同时间下两者差异不显著。发酵条件下,各处理均出现“亚硝峰”,2d时亚硝酸盐含量均高于ADI值;8d时,亚硝酸盐含量均低于ADI值。4g／100mL、6g/100mL、8g,100mL糖添加量发酵条件下,“亚硝峰”比自然发酵、2g／100mL加糖发酵的提前出现,且相同时间下加糖量4g/100mL的亚硝酸盐含量最低。依据亚硝酸盐含量的变化情况表明,短期贮藏（2d内）以冰箱为宜,长期贮藏（多于8d）以发酵为宜,加糖发酵以4g／100mL绵白糖加入量为佳。     

Influence of blanching and freezing broccoli (<Emphasis Type="Italic">Brassica oleracea</Emphasis> var. <Emphasis Type="Italic">italica</Emphasis>) prior to storage and cooking on glucosinolate concentrations and myrosinase activity

Glucosinolates contribute to the chemoprotective effects of Brassica vegetables. The influence of blanching and freezing broccoli, followed by storage or cooking, on its glucosinolate concentration and myrosinase activity was investigated. Myrosinase activity was reduced by 93%, while glucosinolate concentration was unaltered after blanch-freezing broccoli. Blanch-frozen Brassica retained the glucosinolate content of its fresh counterpart after storage at T = −20 °C for up to 90 days. Fresh or blanch-frozen broccoli was stir-fried, boiled, boiled and kept hot for 2 h, or left uncooked. Stir-frying retained the highest glucosinolate concentration and myrosinase activity, regardless of pre-cooking. Boiling and keeping blanch-frozen broccoli hot completely denatured myrosinase and decreased glucosinolate concentration by 42%. Aromatic and indole glucosinolates were reduced to a larger extent than aliphatic glucosinolates, especially when boiled broccoli was kept hot. The final concentration of glucosinolates in Brassica is influenced by cooking, while the myrosinase activity is modified by pre-treatment and subsequent cooking.     

干水菜营养价值研究

以调羹白为原料制成干水菜在广东市场渐为流行,各类方便食品如方便面等也大多配以适量干水菜.实验选用新鲜调羹白,通过感官、Vc和氨基酸含量的分析,研究了长期储存的调羹白在各营养价值方面的缺失情况.结果表明,"干水菜"随储藏天数的增加,感官水平下降,Vc和氨基酸的含量都明显降低.因此,建议消费者从营养膳食角度出发减少干水菜的食用.     

Genotypic effects on the phytochemical quality of seeds and sprouts from commercial broccoli cultivars

Determining ontogenic diversity in vegetables, in general or Brassicas in particular, regarding the bioactive content, is an interesting task since the most promising Brassicaceae foods could have the highest nutritional and health-promoting properties. Therefore, vitamin C, phenolic compounds, glucosinolate content, and total antioxidant capacity were evaluated in commercial cultivars of broccoli (Brassica oleracea var. italica; cv. Nubia, cv. Marathon and cv. Viola) seeds and during the sprouting period. Vitamin C was not detected in dormant seeds and its content increased with the germination, reaching values ranging from 53 (cv. Nubia) to 64 (cv. Marathon) mg/100 g FW, at the end of the monitored period (14days). The total glucosinolate content in seeds and 3-day-old sprouts was higher in cv. Marathon (1005 and 556 mg/100 g FW, respectively), however cv. Viola sprouts registered the highest glucosinolate content 7 and 14 days after sowing (235 and 208 mg/100 g FW, respectively). Aliphatic glucosinolates were more affected by genetic factors than the indolic glucosinolates, being glucoraphanin the predominant glucosinolate in cv. Nubia and cv. Marathon, whereas glucoiberin was the major glucosinolate in cv. Viola. The flavonoid and total phenolic content was significantly higher in cv. Viola. Also, seeds of this cultivar showed the highest antioxidant capacity (2.7 mg Trolox/g FW).     

Stability and antioxidative properties of acylated anthocyanins in three cultivars of red cabbage (Brassica oleracea L. var. capitata L. f. rubra)

BACKGROUND: Red cabbage is rich in acylated anthocyanins. The aim of the experiment has been to determine the stability of anthocyanins in extracts of red cabbage cultivars and examine their antioxidative properties. The (high‐performance liquid chromatographic) HPLC profile of anthocyanins characteristic of each red cabbage cultivar has also been determined. RESULTS: We have used three red cabbage cultivars: cv. Koda, Haco POL and Kissendrup SWE. The HPLC assays enabled us to distinguish nine anthocyanin compounds, which were all classified as cyanidin derivatives. These compounds occurred in different proportions in the three culitvars of red cabbage. The differences were observed in the degradation index of anthocyanins in extracts from the red cabbage cultivars examined, both stored at + 2 °C and frozen. The highest trolox equivalent antioxidant capacity (TEAC) was attained for anthocyanins from cv. Haco POL red cabbage, whereas the lowest value was determined for cv. Koda. CONCLUSION: There were differences in the stability and antioxidative properties of anthocyanin compounds in red cabbage extracts among the cultivars evaluated (Koda, Haco POL and Kissendrup SWE). The highest stability and strongest antioxidative properties were assigned to anthocyanins in extracts from cv. Haco POL. The HPLC profiles imply differences in proportions of anthocyanin compounds present in the three red cabbage cultivars. Copyright © 2009 Society of Chemical Industry     

包菜-黄豆复合发酵保健饮料的研制

以包菜和黄豆为主要原料,通过乳酸菌发酵研制出集包菜和黄豆营养于一体的新型发酵保健饮料.采用正交试验筛选出最佳发酵条件:豆浆与包菜汁最佳配比为1:3,发酵时间24h,接种量8%,乳糖加入量1.25%.复合发酵保健饮料的最佳配方为100mL发酵饮料中加入8g蔗糖、0.25g果胶和0.5gCMC-Na时,饮料口感适中且营养丰富.