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1.
长链脂肪醇开发研究   总被引:10,自引:0,他引:10  
本文介绍对米糠蜡等六种原料制取长链脂肪醇及其脂肪醇组成的研究。  相似文献   

2.
2009年,杭州开博化工有限公司公开了一种组成简单、适用范围较广的环保型混合废纸脱墨剂。该脱墨剂的组成成分有壬基酚聚氧乙烯醚、脂肪醇聚氧乙烯醚硫化钠、脂肪醇聚氧乙烯醚、磺酸、乙醇和水组成。其中,  相似文献   

3.
面包酵母酶解液中水不溶性沉淀的形成机理   总被引:2,自引:0,他引:2  
以导致面包酵母木瓜蛋白酶酶解液浑浊的沉淀物质为研究对象,分析了该沉淀物质的基本化学组成、氨基酸组成、分子量分布以及在不同溶剂和不同pH值缓冲液中的溶解度,从而探讨了该沉淀物的形成机理。研究结果表明,沉淀物质(以干基计)主要组成成分为:蛋白质62.00%、总糖22.80%和灰分15.50%;分离沉淀前后酶解液的分子量分布结果表明,有分子量小于1000 u的肽分子参与沉淀物的构成;氨基酸分析显示,沉淀物质中的疏水氨基酸含量占46%,高于酶解液中的32.03%,说明疏水作用可能是该沉淀物形成的主要推动力;沉淀溶解度定性与定量测定显示沉淀在水和氨水中微溶,且等电点在pH6.5附近。  相似文献   

4.
从提高葡萄酒质量的要求来看,予防葡萄酒的混浊沉淀具有非常重要的意义。为了制定瓶装葡萄酒的合理的工艺流程,研究的第一阶段是确定葡萄沉淀物的性质。测定葡萄酒沉淀物的系统分析法由予备试验和主要试验所组成,均按一定的程序进行。分析前沉淀物的处理如果沉淀很少,应把沉淀物离心或者过滤,离心管中的沉淀物(或者过滤纸上的沉淀物)用蒸馏水洗涤,而后用酒精洗。如果沉淀物易溶于酒精,证明它主要是单宁色素。湿的沉淀物在空气中(或者夹于两层滤纸间)风干。  相似文献   

5.
以导致面包酵母木瓜蛋白酶酶解液浑浊的沉淀物质为研究对象,分析了该沉淀物质的基本化学组成、氨基酸组成、分子量分布以及在不同溶剂和不同pH值缓冲液中的溶解度,从而探讨了该沉淀物的形成机理。研究结果表明,沉淀物质(以干基计)主要组成成分为:蛋白质62.00%、总糖22.80%和灰分15.50%;分离沉淀前后酶解液的分子量分布结果表明,有分子量小于1000 u的肽分子参与沉淀物的构成;氨基酸分析显示,沉淀物质中的疏水氨基酸含量占46%,高于酶解液中的32.03%,说明疏水作用可能是该沉淀物形成的主要推动力;沉淀溶解度定性与定量测定显示沉淀在水和氨水中微溶,且等电点在pH6.5附近。  相似文献   

6.
废报纸脱墨剂的研制   总被引:4,自引:1,他引:4  
本文研究了 T- 80、油酸钠、十二烷基磺酸钠、乙氧基脂肪醇等表面活性剂在废旧新闻纸脱墨中的应用效果,从中筛选出脱墨效果较好的表面活性剂,由它们组成复配脱墨剂,发挥各组分在脱墨中的协同作用.并考察了不同配比条件下的脱墨效果,开发出了 TM系列脱墨剂.  相似文献   

7.
研究了香蕉汁贮藏期间发生二次沉淀的原因。成分分析发现,香蕉汁二次沉淀物中总糖含量占干基的80.25%,气相色谱分析发现,总糖中85.72%的单糖是葡萄糖。沉淀物与碘液反应呈淡紫红色,波长扫描最大光吸收值在480~520nm范围,表明二次沉淀物主要是由糊精组成。虽然沉淀物中含有少量蛋白质与酚类化合物,但糊精老化凝沉是香蕉汁发生二次沉淀的主要原因。  相似文献   

8.
过滤清亮的啤酒也是胶体溶液,在氧化受热、光线、振动等条件下易形成悬浮物和沉淀物。在生产中,清酒和装瓶灭菌后的啤酒静置一段时间后,容易出现悬浮物和沉淀物。一、悬浮物和沉淀物的影响因素1.麦芽质量的影响啤酒生产中一直或断续的出现悬浮物和沉淀物,许多厂想到是麦芽质量有问题或糖化工艺不正确,就采用调换麦芽或对糖化工艺进行调整,如调换麦芽品种、产地、降低麦汁 PH,采用低温浸渍,低温  相似文献   

9.
每日清洗是隐形眼镜护理的重要环节,可是常常被忽略。做不到每天清洗隐形眼镜会加速沉淀物积聚,可能导致不良后果。 研究人员已确定几种与沉淀物有关的临床症状,包括异物感、畏光、红眼、刺激和不适。此外,隐形眼镜沉淀物会缩短戴用时间,增加顾客流失率,造成镜片变色,引起眼病如巨乳头状结膜炎等。 镜片沉淀物的表现形式 沉淀物的出现有多种形式,包括不规则膜、光滑的表面涂层、分散的颗粒或变色。镜片上的沉淀物通常是几种不同形式的混合。  相似文献   

10.
米糠油是一种理想的食用植物油,它不仅脂肪酸组成比较完整、合理,而且含有多种营养物质,例如阿魏酸酯(2~2.5%)、维生素E类同族物(0.2~0.3%)、不皂化物(脂肪醇、甾醇、角鲨烯、三萜烯醇等3.5~6.5%)。合理的脂肪酸结构及组成是其它植物油脂所不及的。这些对降低人体血清胆固醇、防止动脉硬化、高血压等症状具有良好的疗效。  相似文献   

11.
Six lactating Jersey cows were used in a 6 x 6 Latin square with 14-d periods to evaluate different ratios of canola oil and oleamide on nutrient digestibility, plasma fatty acids, and plasma hormones. The control diet contained no added fat. All other diets contained 3.5% added fat consisting of 0, 25, 50, 75, and 100% as oleamide and the remainder as canola oil. Data were collected during the final 4 d of each period. Dry matter intake was reduced by the addition of canola oil to the diet, and further reduced by replacing canola oil with oleamide. Milk yield was not affected by diet but increasing oleamide proportion in the fat supplement caused linear increases in cis-C18:1 and linear decreases in C4 to C16 fatty acids in milk. Adding canola oil reduced total tract digestibilities of fiber and fatty acids, but had no effect on the digestibilities of dry matter or protein. Replacing canola oil with oleamide increased protein digestibility linearly, and increased digestibility of fiber (quartic relationship) and fatty acids (quadratic relationship). Oleic acid concentration in plasma increased by adding canola oil to the diet, and was further increased by replacing canola oil with oleamide. Diet had no effect on plasma concentrations of insulin or IGF-I. Oleamide fed to Jersey cows in this study was highly digestible and had no deleterious effects on total tract digestility of fiber or protein. Increasing oleic acid concentration in plasma lipids while maintaining a constant level of added fat in the ration had no effect on circulating concentrations of insulin or IGF-I in Jerseys.  相似文献   

12.
测定了12种植物油的脂肪酸组成和含量,探讨了利用植物油脂肪酸的指标对不同种类的植物油进行分类和判别的可能性。采用气相色谱法对12种植物油脂肪酸的组成和含量进行测定,利用SPSS 22. 0统计软件进行主成分分析、系统聚类、 K-平均值聚类和判别分析。结果表明:12种植物油的主要共有组成为油酸(15.635%~66.569%)和亚油酸(10.521%~58.227%),其中棉籽油(16.285%)中单不饱和脂肪酸含量最低,橄榄油(67.628%)中单不饱和脂肪酸含量最高;橄榄油(11.284%)中多不饱和脂肪酸含量最低,核桃油(67.167%)中多不饱和脂肪酸含量最高;12种植物油中不饱和度最小为棉籽油3.235,最大为低芥酸菜籽油14.672。主成分分析降维得到5个主成分,利用主成分分析数据,依次进行聚类分析和判别分析,系统聚类和K-平均值聚类结果一致,可对12种植物油聚类区别,通过判别分析建立了3个典则判别函数,对不同植物油的分类和判别的效果良好。  相似文献   

13.
目的研究28种功能性食用油脂的脂肪酸组成,包括8种国家新食品原料(新资源食品)目录油脂。方法采用气相色谱-氢火焰离子化检测器(gas chromatography-flame ionization detection,GC-FID)方法对28种油脂的脂肪酸组成进行研究。在GC-FID图谱基础上,得出了所测的28种植物油脂中37种脂肪酸的指纹图谱。根据脂肪酸的保留时间和峰面积进行定性和相对定量,进而分析饱和脂肪酸(saturated fatty acid,SFA)、不饱和脂肪酸(unsaturated fatty acid,UFA)、多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)、单不饱和脂肪酸(monounsaturated fatty acid,MUFA)组成,从而分析样品的脂肪酸组成。结果在28种功能性油脂中,芍药籽油、芥花油、美藤果油、文冠果油、星油藤种子、翅果油等10种油脂UFA含量都在90%以上;MUFA含量最高为澳洲坚果油80.3%,其中,PUFA含量以美藤果油最多,达到82.0%,星油藤种子油次之,为81.1%,二者亚油酸(C18:2)和亚麻酸(C18:3)均含量高达40%;漆树种仁油、毗黎勒油、秋葵籽油、油瓜油的SFA含量均超过30%。结论该研究对探讨利用脂肪酸指标评价新型功能性油脂的营养价值及其开发利用具有指导意义。  相似文献   

14.
The aim of this study was to evaluate the inclusion of different oil sources and dietary supplementation with vitamin E on the composition of fatty acids in rooster meat. Two hundred and forty 30‐week‐old White Leghorn roosters were distributed in a completely randomized factorial arrangement of 5 × 2, using five oil sources (sunflower, soybean, canola, linseed and fish) and two levels of antioxidant (30 and 400 mg vitamin E kg?1 of diet). The intake of fish and canola oil in the diet reduced (P < 0.05) the content of saturated and unsaturated fatty acids in the thigh meat. Amongst the unsaturated fatty acids in the thigh, the fish and canola oil reduced (P < 0.05) the level of ω6 fatty acid, with a consequent decrease in the ratio ω6:ω3. The diet with fish oil increased (P < 0.05) the content of C22:6ω3 in the thigh meat. The use of linseed oil resulted in a significant reduction of the ratio of ω6:ω3 fatty acid in the thigh. The use of soybean oil in the diet increased (P < 0.05) the content of saturated and unsaturated fatty acids in the thigh, specifically in the content of ω6. The inclusion of vitamin E increased the polyunsaturated fatty acids in the chest meat, such as C18:3ω3, C20:5ω3 and C22:6ω3. Copyright © 2004 Society of Chemical Industry  相似文献   

15.
Oleamide was previously reported to resist ruminal biohydrogenation and elevate milk oleic acid concentration when fed to lactating Holstein cows. To determine if Jersey cows responded similarly to oleamide, four lactating Jersey cows (mean 417 kg of body weight and 64 days in milk) were fed four diets in a 4x4 Latin square with 2-wk periods. Diets were total mixed ration containing 47% corn silage and 53% concentrate (dry matter basis) and were supplemented with no added fat (control), or with 3.5% added fat from either higholeic canola oil, a commercial source of oleamide, or oleamide synthesized from oleic acid and urea. The canola oil supplement had no effect on milk yield or composition. Compared to canola oil, the oleamide supplements reduced milk yield, dry matter intake, and milk fat and protein contents. Milk oleic acid concentration increased from 17.4% of total fatty acids for the control diet to 22.1% for the canola oil diet. Both oleamides further increased milk oleic acid to 30.0 and 27.1% of total fatty acids for the commercial and synthesized oleamides, respectively. Milk palmitic acid was reduced and stearic acid was increased by all fat supplements but more so by the oleamides than by the canola oil. Consistent with previous reports that fatty acyl amides resist ruminal biohydrogenation, feeding oleamide to Jersey cows in this study increased milk oleic acid concentration but had negative effects on feed intake and milk yield.  相似文献   

16.
The objective was to determine the influence of dietary lipid on total and sn-2 fatty acid composition and triglyceride structure of milk fat in lactating Holstein cows. Five primiparous Holstein cows surgically fitted with ruminal and duodenal cannulas were used in a 4 x 5 incomplete Latin square. All cows received a basal diet. Treatments consisted of a basal diet with no supplemental canola oil (control), basal diet with canola oil added to the concentrate portion of the diet to provide 1.6% fat, basal diet with 330 g of canola oil infused directly into the rumen, and basal diet with 330 g of canola oil infused directly into the abomasum. Canola oil treatments decreased palmitic acid and increased oleic acid content of milk fat compared with the control. Stearate was higher when canola oil was rumen available compared with control and abomasal infusion. Abomasal infusion increased linoleic and linoleic acids in milk fat compared with the other treatments. The sn-2 fatty acid composition reflected total fatty acid composition. All canola oil treatments reduced palmitic acid and increased oleic acid content at the sn-2 position. Changes in sn-2 composition reflect specificity of the acyl transferases and substrate concentration. Triglyceride composition reported as carbon number was altered by canola oil. Triglycerides in carbon number C50, C52, and C54 were increased while C32, C34, and C36 were decreased.  相似文献   

17.
We determined the effects of feeding canola oil or infusing it into the abomasum on rumen fermentation, nutrient digestibility, duodenal flows of fatty acids, and milk composition in Holstein cows. Five ruminally and duodenally cannulated Holstein cows in late lactation were used in a 3 x 5 incomplete Latin square design. Treatments were 1) Control: basal diet (CON), 2) Control+supplementation of canola oil at 1 kg/d in the feed (FED), and 3) Control+abomasal infusion of canola oil at 1 kg/d (INF). Compared with CON, feed intake, ruminal fermentation characteristics, ruminal and total tract digestibilities of nutrients were not significantly affected by FED treatment but duodenal flows and milk concentrations of fatty acids (FA) such as trans-11 18:1 and cis-9 trans-11 18:2 (conjugated linoleic acid, CLA) were increased. In contrast to the effects of FED, INF reduced feed intake, total VFA production, intestinal flows of nutrients, FA digestibility and yields of milk and milk fat. Both FED and INF significantly reduced the proportions of saturated and medium-chain FA, and increased cis 18:1 in milk. Concentrations of 18:2n-6 and 18:3n-3 in milk were increased nearly 2-fold with INF relative to CON. Dietary or postruminal supplementation of canola oil to late-lactation cows reduced saturated FA and increased unsaturated C18 in milk but nutrient digestion was adversely affected with abomasal infusion of canola oil.  相似文献   

18.
Monola oil, a high oleic acid canola cultivar, and canola oil were evaluated as replacers of fish oil at three levels of inclusion (60%, 75% and 90%) in rainbow trout diets. After a 27-week grow-out cycle, the diet-induced effects on growth, fatty acid metabolism and final eating quality were assessed. Overall, no effects were noted for growth, feed utilisation or fish biometry, and the fatty acid composition of fish fillets mirrored that of the diets. Dietary treatments affected fillet lipid oxidation (free malondialdehyde), pigmentation and flavour volatile compounds, but only minor effects on sensorial attributes were detected. Ultimately, both oils were demonstrated to possess, to differing extents, suitable qualities to adequately replace fish oil from the perspective of fish performance and final product quality. However, further research is required to alleviate on-going issues associated with the loss of health promoting attributes (n-3 long chain polyunsaturated fatty acids) of final farmed products.  相似文献   

19.
双低菜籽营养调和油的研制   总被引:1,自引:1,他引:1  
双低菜籽油富含油酸,以双低菜籽油为主研制了两种适合不同人群的调和油,两种产品油酸含量接近50%,不饱和脂肪酸总量达80%以上,脂肪酸组成合理,n-6与n-3 PUFA比例为4.7:1和5.6:1.油品氧化稳定性良好,品质达到国家规定标准,且价格合适.  相似文献   

20.
The influence of seven cooking methods (boiling, conventional baking, microwave baking, grilling, deep-frying in soybean oil, canola oil, or partially hydrogenated vegetable oil) on the oxidation, proximate and fatty acid composition of silver catfish (Rhamdia quelen) fillets was evaluated. All the treatments reduced moisture and increased the protein content. The free fatty acid content of the fillets was significantly reduced by the different cooking methods, while conjugated diene levels and peroxide values decreased for all fried samples, but remained constant in the samples subjected to the other cooking methods. Boiling and baking increased thiobarbituric acid reactive substances (TBARS), while grilling and frying did not change TBARS. Boiling, baking, and grilling did not affect the silver catfish fillets fatty acid composition. Frying in canola oil increased n−3/n−6 ratio, while frying in soybean oil increased the general polyunsaturated fatty acid content, and frying in hydrogenated vegetable oil incorporated trans fatty acids in the fillets.  相似文献   

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