梭鱼脂肪及脂肪酸成分分析和评价

为了解梭鱼的应用价值,对江苏沿海滩涂池塘养殖梭鱼（均质量（445.8±26.9）g）6 种组织（鱼头、鱼皮、背肌、腹肌、肝脏、腹脂）的脂肪分布、性质、脂肪酸组成进行分析和评价。索氏提取法测定组织中脂肪含量,滴定法测定脂肪的碘值和酸价,气相色谱-质谱法分析脂肪酸的组成。结果表明：梭鱼体内各组织脂肪分布差异显著（P＜0.05）,其中背肌和腹肌中脂肪含量分别为3.66%、10.16%;各组织脂肪的不饱和程度较高,碘值为90～106 g/100 g;各组织脂肪酸价较高,介于4～9 mg KOH/g之间;梭鱼脂肪中C22∶6n 3和C20∶5n 3含量丰富,品质好;鱼头、背肌、腹肌中饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸构成比例约为1∶1.5∶（0.7～0.8）,n-3/n-6多不饱和脂肪酸比值在0.7～0.8之间,组成合理;肝脏和腹脂中脂肪含量丰富,其中含有大量的n-3和n-6多不饱和脂肪酸,因此梭鱼的内脏也具有较好的可利用前景。     

平榛脂肪及脂肪酸成分分析和综合评价

榛子为世界上四大木本油料坚果之一。本研究采用索氏提取法、气相色谱法分别对26个平榛优良单株和2个欧榛品种的果仁粗脂肪含量、油的脂肪酸组成进行测定。运用面积归一法、SAS方差和聚类分析结果表明：泰山平榛、蒙山平榛和2个欧榛的粗脂肪平均含量分别为59．02％、59．61％和58．83％,油酸平均含量分别为81．60％、85．45％和80．66％,亚油酸平均含量分别为13．44％、8．93％和11．53％。综合评价得出,泰山17个单株和蒙山4个单株为最优单株,其粗脂肪含量、油酸和亚油酸含量的平均值分别达到了60．52％、83．50％和11．58％。本文对榛子果仁成分及良种选择进行了评价。     

牦牛肝脏中脂肪含量与食用品质、脂肪酸组成的相关性

研究牦牛肝脏中脂肪含量与食用品质及脂肪酸组成之间的关系。以海北牦牛为研究对象、当地同龄黄牛为对照,采用内标法对肝脏的脂肪酸组成进行测定并对脂肪含量与食用品质、脂肪酸组成进行相关性分析。结果显示：牦牛肝脏色度a*值极显著高于对照组（P＜0.01）,失水率极显著低于对照组（P＜0.01）;饱和脂肪酸含量极显著低于对照组（P＜0.01）;两者的功能性脂肪酸有极显著差异（P＜0.01）;牦牛肝脏P/S值为0.51,符合世界卫生组织推荐的大于0.4的标准,n-6/n-3值小于营养学上建议的标准。相关性分析表明：肝脏脂肪含量与失水率呈极显著正相关（P＜0.01）;肝脏脂肪含量与饱和脂肪酸、单不饱和脂肪酸、硬脂酸、二十碳五烯酸、二十二碳六烯酸含量呈显著正相关（P＜0.05）,与多不饱和脂肪酸含量呈极显著负相关（P＜0.01）。因此,牦牛肝脏具有优良的食用品质和较高的营养价值。     

欧榛脂肪及脂肪酸成分分析及评价

采用索氏提取法、气相色谱法分别对13个欧榛品种和平榛的果仁粗脂肪含量、脂肪酸组成进行测定.运用面积归一法、SAS方差和聚类分析处理数据,结果表明:13个欧榛品种和平榛的粗脂肪平均含量分别为60.60%和58.96%,油酸平均含量分别为83.43%和82.08%,亚油酸的平均含量分别为9.19%和12.66%.综合评价表明,1#、2#、3#、5#、7#、41#、88#、H3#和H4#为优良品种,粗脂肪含量分别为61.33%、64.94%、65.99%、61.46%、64.24%、59.61%、62.23%、62.34%和61.41%,油酸含量分别为84.17%、85.13%、87.59%、83.69%、87.13%、86.99%、84.29%、86.61%和83.93%,亚油酸含量分别为8.92%、7.70%、6.02%、8.26%、6.59%、7.18%、10.59%、8.41%和4.67%.此外,还对果仁成分及良种选择进行了评价.     

大庆盐碱地角碱蓬籽粒含油量及其脂肪酸组成研究

研究了黑龙江省大庆盐碱地角碱蓬籽粒含油量及其脂肪酸的组成,采用索氏提取法和气相色谱分析法对大庆市盐碱地生长的角碱蓬籽粒含油量及脂肪酸成分进行了测定及分析.结果表明:大庆市盐碱地生长的角碱蓬籽粒含油量为25.34%,其中棕榈酸为5.71%、棕榈油酸为2.05%、硬脂酸为0.07%、油酸为10.44%、亚油酸为80.03%、亚麻酸为1.69%,亚油酸含量最高,不饱和脂肪酸的含量占94.21%.大庆地区盐碱地角碱蓬亚油酸的含量远高于紫苏的含量,与月见草和红花籽油的含量相当,具有较高的开发和利用价值.     

Fatty Acid Composition and Caloric Value of Ground Beef Containing Low Levels of Fat

Ground beef patties containing five different levels of fat – 5, 10, 15, 20, and 25%– were cooked by boiling, browning, pan-frying, microwaving, roasting or broiling. Proximate composition, fat retention, energy content (kcal/100g), and fatty acid composition of raw and cooked patties were examined. Percentage fat retention decreased as fat content of the raw patty increased. Microwaving to “well done” and boiling resulted in ground beef with less fat than other methods of cooking at the higher fat levels. The proportion of fatty acids changed very little with increasing fat percentage and because of cooking method.     

15种淡水鱼肌肉脂肪含量及脂肪酸组成分析

为比较淡水鱼肌肉脂肪酸在鱼类科、目以及种属间的差异,本文采用氯仿-甲醇(体积比=2:1)法提取15种淡水鱼背部肌肉的粗脂肪,运用气相色谱-质谱联用方法,分析了15种淡水鱼脂肪酸的组成。结果表明,15种淡水鱼肌肉粗脂肪含量在3.76%~14.74%,15种淡水鱼共检出24种脂肪酸,其中8种饱和脂肪酸(SFA),5种单不饱和脂肪酸(MUFA)和11种多不饱和脂肪酸(PUFA)。不同淡水鱼脂肪酸除个别有差异外,其他组成基本相同,但其含量因淡水鱼所在目、科和种属不同存在显著性差异,多不饱和脂肪酸含量最高,均在35%以上。不同鱼种的粗脂肪中EPA和DHA总含量有所差异,鲈鱼粗脂肪中DHA和EPA最高,总含量达到30%,而泥鳅粗脂肪中的EPA和DHA总含量仅为8.51%。部分鱼种可以作为EPA和DHA的良好膳食来源,具有较高的利用和开发价值。     

猪五花肉红烧过程中脂肪和脂肪酸的变化规律

目的：探讨以猪五花肉为原料的红烧肉加工过程中脂肪和脂肪酸的变化,以期对红烧肉的风味、营养、质地等研究提供参考。方法：对红烧肉加工过程中原料、油炸、炖煮过程样品（0～2 h,每30 min取样）以及成品的粗脂肪含量、过氧化值（peroxide value,POV）、硫代巴比妥酸（thiobarbituric acid reactive substances,TBARS）值以及脂肪酸含量进行测定。结果：五花肉红烧过程中脂肪含量显著下降（P＜0.05）,成品红烧肉脂肪含量比原料肉下降12.14%;POV先增大后减小,在炖煮30 min达到最大值;TBARS值逐渐增大,在炖煮过程中变化显著（P＜0.05）;油酸、棕榈酸、亚油酸和硬脂酸是五花肉脂肪中的主要脂肪酸,在红烧过程中饱和脂肪酸（saturatedfatty acid,SFA）含量变化不大（P＞0.05）,单不饱和脂肪酸（monounsaturated fatty acid,MUFA）含量显著上升（P＜0.05）,多不饱和脂肪酸（polyunsaturated fatty acid,PUFA）含量显著下降。结论：五花肉红烧过程中脂肪含量下降、脂肪发生适度氧化、脂肪酸组分构成发生了改变。     

不同部位牦牛肉氨基酸、脂肪酸含量分析与营养价值评价

为明确不同部位牦牛肉氨基酸、脂肪酸等营养物质含量,采集西藏那曲牦牛的上脑、里脊、外脊、米龙、臀肉、腱子肉、腹肉、肩肉及胸肉9 个部位分割肉,测定其蛋白质、脂肪、灰分、氨基酸和脂肪酸组成。结果表明：不同部位牦牛肉的蛋白质含量为19.30%～24.20%,其中腹肉中蛋白质含量最低,外脊中最高;脂肪含量为1.03%～22.47%,腹肉中脂肪含量显著高于其他各部位,米龙、外脊、臀肉和肩肉中脂肪含量较低,不足1.5%。在测定的18 种氨基酸中,谷氨酸含量最高,其次是赖氨酸、天冬氨酸、亮氨酸和精氨酸;腹肉中氨基酸含量显著低于其他部位（P＜0.05）,9 个不同部位牦牛肉中必需氨基酸占总氨基酸的比例为39.03%～40.00%,与联合国粮农组织/世界卫生组织的推荐值接近;里脊和外脊能够满足所有膳食氨基酸需要,上脑、米龙、臀肉、腱子肉、腹肉、肩肉及胸肉中,缬氨酸是限制性氨基酸。脂肪酸总量由大到小为腹肉＞上脑＞里脊＞臀肉＞外脊＞胸肉＞肩肉＞腱子肉＞米龙,油酸、棕榈酸和硬脂酸是牦牛肉中主要的脂肪酸,二十二碳六烯酸、二十碳五烯酸等n-3脂肪酸含量较少,n-6/n-3比值高于膳食推荐值。以常规营养组分、氨基酸组成和脂肪酸组成分别进行聚类分析,总体可分为腹肉、上脑与其他部位肉三大类。综上所述,不同部位牦牛肉中蛋白质、脂肪、氨基酸及脂肪酸等营养物质含量存在差异。     

Lipid Content and Fatty Acid Composition in Bamboo Shoots

Lipids from bamboo shoots (Phyllostachys pubescens), peeled and divided from top to base, were extracted and fractionated into three classes, and each class separated into constituent components by thin-layer chromatography (TLC). Fatty acid composition and amount of separated lipids were determined. Total lipids (TL) ranged from 800 (top) to 380 mg (base) per 100g fresh weight and the ratio of nonpolar lipids (NPL):glycolipids (GL):phospholipids (PL) was about 17:27:56. The main fatty acids of the three lipid classes were palmitic, linoleic and linolenic acids, but composition was remarkably different among these fractions. The fatty acid composition of triglycerides (TG) was similar to the original NPL. Palmitic acid was almost all located in 1-, 3-position, linoleic acid mainly located in 2-position of TG, while linolenic acid was distributed in each position. Digalactosyl diglyceride (DGDG) and monogalactosyl diglyceride (MGDG) were the main components of GL; the average of the former had about 37% linoleic and 29% linolenic acids, while the latter had about 25% linoleic and 62% linolenic acids. Bamboo shoots contained 9 PL fractions, the major being phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE). PC contained about 48% linoleic, 31% palmitic and 11% linolenic acids, and PE also had the similar tendency as PC.     

河北省核桃坚果蛋白质、脂肪及脂肪酸组成分析

目的:为深入了解河北省核桃资源现状,为优良核桃品种的选育和种质创新提供科学依据。方法:以河北省103份核桃资源为研究对象,对其蛋白质、脂肪及脂肪酸组分进行变异分析、相关性分析和聚类分析。结果:103份核桃资源脂肪、蛋白质的平均含量分别为62.15%、16.66%,油酸、亚油酸等不饱和脂肪酸的平均含量分别为17.31%、64.56%。各指标变异系数的变化范围为7.40%~31.41%,其中油酸的变异系数最大,亚油酸的变异系数最小;各指标的香农-威纳指数的变化范围为1.89~2.10,其中蛋白质的香农-威纳指数最高。相关性分析发现油酸含量与亚油酸、α-亚麻酸含量分别呈极显著负相关（P<0.01）,与花生烯酸呈极显著正相关（P<0.01）,且不饱和脂肪酸组分关联较紧密。聚类分析采用离差平方和方法,在欧氏距离D=9.75处可将103份核桃资源分为5个群组（I、II、III、 IV 和 V),各含有38、4、24、16和24个资源,其中群组Ⅱ为高蛋白、高脂肪、高亚油酸资源,群组Ⅴ为高油酸、低亚油酸资源。结论:本研究中,103份核桃资源的遗传多样性丰富,资源特色明显,王永久、史文海、王春安、早硕可作为高蛋白、高脂肪、高亚油酸资源进行研究,为河北省核桃特色油脂资源的开发利用和良种选育提供依据。     

3 种方法提取燕麦麸蛋白及其产物的比较

通过单因素和正交试验优化碱法、超声辅助碱法及超声辅助酶碱法提取燕麦蛋白的工艺。结果表明：在最佳条件下燕麦蛋白的提取率分别可达31.96%、39.31%、61.43%;根据燕麦蛋白在不同pH 值条件下的溶解性及沉淀率,确定碱法、超声辅助碱法和超声辅助酶碱法所提燕麦蛋白的等电点分别为4.6、3.6、3.8,沉淀率分别为57.92%、63.24%、72.24%;通过氨基酸组成分析和营养价值的评定,可知3 种提取方法所提取的燕麦蛋白符合FAO/WHO 推荐的模式,超声辅助酶碱法所提取的燕麦蛋白的必需氨基酸指数(EAAI)较其他两种方法的高,说明其营养价值较高。     

超临界-CO2 萃取燕麦麸油及其脂肪酸分析

采用正交试验考察超临界CO2 萃取燕麦麸皮中燕麦油的最佳工艺技术参数,用GC-MS 分析燕麦麸油的脂肪酸组成。结果表明：CO2 超临界萃取的最佳工艺参数为压力15MPa、温度35℃、时间3h,所得燕麦麸油澄清透明,呈金黄色,具有特殊的麦香味。超临界CO2 萃取燕麦麸油中的脂肪酸主要有棕榈酸17.60% 、硬脂酸1.32%、油酸40.15%、亚油酸37.55%、亚麻酸1.89% 和反油酸1.52%;而石油醚萃取燕麦麸油中的脂肪酸主要有15.90%、1.67%、38.38 %、41.67%、1.63% 和1.32%。超临界CO2 萃取与石油醚萃取燕麦麸油中的总不饱和脂肪酸分别占81.11% 和83.00%。     

Energy Value of a Fat High in Stearic Acid

A fat containing 92.1% stearic acid (tristearin) was evaluated for energy value using shortening (9 kcal/g) and mineral oil (0 kcal/g) as controls and young rats as the test model. Energy value was calculated based on efficiency of conversion of estimated gross energy intake to carcass energy over a 3-wk period. Rats fed the shortening-based diet deposited more than double the fat and significantly more protein in the carcass than rats fed the tristearin-based diet. Rats fed the tristearin-based diet deposited significantly more fat and protein than rats fed the mineral oil-based diet. Based on these observations, the estimated energy value of tristearin was calculated as 3 kcal/g.     

Trans Fatty Acid Content of Selected Foods in an African-American Community

ABSTRACT:  Trans fatty acid content was examined in several grocery foods and fast foods in an African-American community. Food samples were selected based on the frequency of use among this population group in the local community. Samples were collected 3 times with an interval of 1 wk. Total fat content was analyzed by Soxhlet method. Fatty acids profile, including trans fatty acids, was analyzed by GC–MS. In grocery foods, no trans fatty acids were detected in fish sticks, salad dressing, mayonnaise, muffin, and potato chips. Margarine contained the highest trans fatty acid at a level of 19.13%. The trans fatty acid level in crackers, cookies, butter, chicken patties, and biscuits mix ranged from 0.51% to 1.77%. In fast foods, no trans fat was detected in dressing. All the fried food and bakery food sampled in this study contain trans fat. The level varied from 2.07% to 10.30%. The principal trans fatty acid was trans 18:1. Other trans fatty acids found were trans 18:2, trans 19:1, and trans 16:1. In a total of 23 food samples, 16 of them were found to contain trans fatty acid. The results demonstrated that trans fat is commonly found in foods of the African-American community. The trans fatty acids content in tested samples varied from 0% to 19.13%.     

光山县长林系列油茶良种茶籽脂肪含量和脂肪酸组成分析

从河南省林木品种审定委员会认定的适宜在本地区推广的长林系列品种中选出具有代表性的主栽油茶品种长林18号、40号、53号和配栽油茶品种长林166号,采用气相色谱-质谱法(GC-MS)对4个油茶品种茶籽仁中脂肪酸组成和含量进行分析,检验了其干籽出仁率和脂肪含量,并对脂肪含量及脂肪酸组分进行了相关性分析。结果表明:3个主栽品种与1个配栽品种干籽出仁率的差异达到了显著水平(p0.05),但不同品种茶籽脂肪含量差异不大;共检测到了17种脂肪酸组分,其中,茶籽仁中常量组分顺-油酸的含量26.25%～30.82%、棕榈酸的含量2.86%～3.22%、亚油酸的含量3.25%～3.86%。长林40号茶籽中饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸比值为1:6.08:1.05,最接近国际营养学家提出油脂中三类脂肪酸的最佳供能比1:6:1。相关性分析显示,脂肪含量与棕榈酸有一定的相关性,相关系数达到了0.64。结合河南省林木品种审定委员会的研究结论可得,长林40号油茶良种不仅产量高、抗性强,而且干籽出仁率高、含油量高,茶籽脂肪酸组成合理,综合性状优于其他三个品种。     

Lipid and Fatty Acid Composition of Selected Fungi Grown on Whey Medium

The molds Aspergillus nidulans, Penicillium frequentans, and Fusarium lycopersicum were tested for lipid production when grown on a deproteinized whey medium. F. lycopersicum produced highest total lipid (38.56%) followed by A. nidulans LC-1 (16.90%) and P. frequentans (10.53%). Triglycerides and phospholipids were the predominant components in the neutral lipid fraction followed by partial glycerides, free fatty acids and nonsaponifiable matter. Phospholipid content was highest in P. frequentans. Palmitic, stearic, oleic and linoleic acids were the major fatty acids and their relative concentrations varied among the three fungi. Lower chain fatty acids were absent.