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研究了超声辅助提取葵花籽黄酮的最佳工艺。通过单因素实验选取超声功率、提取温度、液料比、提取时间为考察因素,利用响应面法Box-Behnken设计对提取葵花籽黄酮工艺参数进行优化,并用DPPH·法评价葵花籽黄酮体外抗氧化活性。结果表明:超声辅助提取葵花籽黄酮的最优工艺参数为超声功率120 W、提取温度64℃、液料比33∶1、提取时间28 min,在此条件下,葵花籽黄酮得率为1.91%;葵花籽黄酮对DPPH·清除率IC50为0.09 mg/m L,优于食品抗氧化剂BHT对DPPH·清除率(IC_(50)为0.11 mg/m L);与传统的索氏提取法对比,超声辅助法提取葵花籽黄酮时间短、节能和得率高。 相似文献
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微波辅助回流提取葵花籽粕绿原酸的研究 总被引:1,自引:0,他引:1
以微波辅助回流提取的方法从葵花籽粕中提取绿原酸。研究了微波辅助提取绿原酸过程中料液比、微波辐射功率、乙醇体积分数以及提取时间对绿原酸得率影响的单因素试验,并在单因素试验基础上进行了正交试验,得出优化的微波辅助回流提取参数为:料液比1∶18、微波辐射功率390 W、乙醇体积分数35%和提取时间20 min,在此条件下绿原酸提取率达到94.6%、得率为2.11%。对提取的绿原酸产品进行抗氧化试验,结果表明葵花籽粕绿原酸对DPPH自由基有显著清除作用,其对DPPH自由基的EC50值为2.6 mg/L。 相似文献
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沙棘叶中绿原酸提取工艺研究 总被引:1,自引:0,他引:1
在单因素试验的基础上,采用正交试验的方法,对水煎煮法和酶解法提取沙棘叶中绿原酸的工艺条件进行了优化。试验结果表明:水煎煮法最佳提取工艺条件为:料液比(g∶mL)1∶35,煎煮时间1.0 h,煎煮次数3次。该条件下,沙棘叶中绿原酸提取率为2.42%。酶解法最佳提取工艺条件为:以加5%纤维素酶的pH 4.5的酸性水为提取剂,料液比(g∶mL)1∶15,温度50℃,提取时间1.0 h。该条件下,绿原酸提取率为3.49%。酶解法与水煎煮法相比,绿原酸提取率提高了44.2%。 相似文献
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以脱去绿原酸后的葵花籽粕作为原料,以蛋白质提取率为指标,通过单因素和正交试验确定碱溶酸沉法制备葵花籽粕蛋白的最优工艺条件,使用蛋白层析仪通过阴离子交换层析对粗蛋白进行分离纯化。结果表明:葵花籽粕蛋白最优提取工艺为:料液比1:20,温度45℃,时间30 min,碱液pH12;在此条件下,葵花籽粕蛋白提取率为61.04%±0.24%,蛋白含量(以蛋白质含量计)为66.94%±0.24%;葵花籽粕蛋白质分离纯化最优工艺为:上样量3 mL、洗脱液流速0.4 mL/min,葵花籽粕蛋白含量(以蛋白质含量计)为93.20%±1.37%,比纯化前提高了39.23%。 相似文献
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Crushed sunflower, flax, or canola seeds in lactating dairy cow diets: Effects on methane production, rumen fermentation, and milk production 总被引:1,自引:0,他引:1
The objective of this study was to investigate the potential of reducing enteric methane production from dairy cows by incorporating into the diet various sources of long-chain FA varying in their degree of saturation and ruminal availability. The experiment was conducted as a crossover design with 16 lactating dairy cows maintained in 2 groups and fed 4 dietary treatments in four 28-d periods. Eight ruminally cannulated primiparous cows (96 ± 18 d in milk) were assigned to group 1 and 8 multiparous cows (130 ± 31 d in milk) were assigned to group 2. The dietary treatments were: 1) a commercial source of calcium salts of long-chain fatty acids (CTL), 2) crushed sunflower seeds (SS), 3) crushed flaxseed (FS), and 4) crushed canola seed (CS). The oilseeds added 3.1 to 4.2% fat to the diet (DM basis). All 3 oilseed treatments decreased methane production (g/d) by an average of 13%. When corrected for differences in dry matter intake (DMI), compared with CTL, methane production (g/kg of DM intake) was decreased by feeding FS (−18%) or CS (−16%) and was only numerically decreased (−10%) by feeding SS. However, compared with the CTL, feeding SS or FS lowered digestible DMI by 16 and 9%, respectively, because of lowered digestibility. Thus, only CS lowered methane per unit of digestible DM intake. Feeding SS and CS decreased rumen protozoal counts, but there were no treatment effects on mean ruminal pH or total volatile fatty acid concentration. Milk efficiency (3.5% fat corrected milk/DMI), milk yield, and component yield and concentrations were not affected by oilseed treatments. The study shows that adding sources of long-chain fatty acids to the diet in the form of processed oilseeds can be an effective means of reducing methane emissions. However, for some oilseeds such as SS or FS, the reduction in methane can be at the expense of diet digestibility. The use of crushed CS offers a means of mitigating methane without negatively affecting diet digestibility, and hence, milk production. 相似文献
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以油葵、食葵的葵花籽仁除油后乙醇提取物为研究对象,在测定其提取物中总酚酸含量的基础上,用K3[Fe(CN)6]测定了它们的还原力;采用D-脱氧核糖-铁体系、超氧阴离子自由基体系、二苯代苦味酰基自由基(DPPH.)体系进行抗氧化活性的研究,并同Vc进行了比较。结果表明:油葵、食葵的葵花籽仁粕乙醇提取物均有显著的抗氧化性,呈剂量效应关系,其中葵花籽仁粕乙醇提取物的抗氧化活性与其总酚含量密切相关。当葵花籽仁粕多酚浓度为0.05 mg/mL时,对DPPH.的清除率都超过了95%;当多酚浓度为0.2 mg/mL时,对超氧阴离子自由基的清除率,油葵、食葵分别为57.83%4、5.24%;对.OH的清除率,油葵、食葵分别达到77.61%6、8%;在实验浓度范围内0.005 mg/mL~0.2 mg/mL,葵花籽粕乙醇提取物的抗氧化性高于VC。 相似文献
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目的对葵花籽和南瓜子水分测定方法进行比较与分析。方法比较几种预处理条件下105℃恒重法和130℃定时定温烘干法对葵花籽和南瓜子水分含量的影响,以确定干燥温度对样品水分含量的影响。并于130℃定时定温烘干法对两种样品进行10次重复试验,确定同一干燥条件下,不同预处理方法对不同样品测得水分结果是否有显著差异。结果利用整粒粉碎方法处理葵花籽、南瓜子并在130℃定时定温烘干方法测出的水分含量更接近真实值。结论从快速、准确等方面综合考虑,建议使用130℃定时定温烘干法,用粉碎机整粒粉碎的方法对瓜子样品进行水分检测。 相似文献
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目的考察烹饪过程中葵花籽油的品质变化规律。方法选取非重复性的短时高温烹饪方式,考察器具材质、温度、时间和食品成分对葵花籽油过氧化值、酸值和脂肪酸组成的影响。结果葵花籽油的过氧化值变化受器具材质、烹饪温度和时间的交互影响,在不锈钢锅210℃高温烹饪8 min的条件下,食品成分(水、食盐、蔗糖、大豆分离蛋白)添加对过氧化值无明显影响。烹饪条件及食品成分添加对葵花籽油酸值的影响程度偏弱,但蔗糖添加可致酸值显著增加(P0.05)。葵花籽油主要由亚油酸(61.81%)、油酸(31.64%)、棕榈酸(2.50%)和硬脂酸(1.64%)组成,经不同条件烹饪处理后,其脂肪酸组成比例并未发生显著变化。结论作为食用油的质量评价指标,过氧化值、酸值和脂肪酸组成并不能有效反映其烹饪品质。 相似文献
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Aflatoxin content of 173 sunflower and safflower seeds was determined by HPLC with immunoaffinity column (IAC) clean-up and fluorometric detection. Aflatoxin B1 contamination was found in 111 samples: in 8 of the sunflower seed samples (16%) at a mean level of 40.68?ng?g?1 and in 103 safflower seed samples (83.7%) at a mean level of 2.81?±?0.44?ng?g?1. In 5 sunflower seed samples and 1 safflower seed sample, aflatoxin B1 levels were higher than the maximum levels of AFB1 under Iran regulations (5?ng?g?1). Aflatoxin B1 levels in 5 sunflower and 2 safflower seed samples were higher than the European Union maximum limit (2?ng?g?1). 相似文献
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为减缓葵花籽油进口对我国油葵产业的冲击,保障我国葵花籽油供给稳定,更好地满足我国居民对特色油脂不断增长的消费需求,在分析我国葵花籽油进口贸易特征的基础上,探究背后的成因并提出应对策略。结果表明:近年来,我国葵花籽油进口呈增长快、依存度高、来源地集中等特征;其原因主要有进口价格优势,国内产量增长慢,全球葵花籽生产分布相对集中。据此建议,扩大我国油葵种植面积,实现规模化种植,保障产量稳定增长;提高我国油葵生产效率,实现降本增效,提升国际竞争力;大力发展我国油葵压榨及相关产业,同时用好国外资源,有效满足我国葵花籽油的需求。 相似文献