鱿鱼肝脏中鱼精油的制备技术及其脂肪酸成分分析

通过对鱿鱼肝脏中鱼油的研究,为鱿鱼及其下脚料的高效利用奠定了理论基础。采用高压蒸煮法和气相色谱/质谱法等技术对鱼油及其脂肪酸成分进行研究。实验得出:加入鱿鱼肝脏1.5倍体积的水,鱼油提取率最高。鱼油精制的条件为:添加体积分数80%磷酸脱胶;采用氢氧化钠脱酸,添加量为粗鱼油的实际酸价来确定;添加量为20%的活性炭脱色;旋转蒸发仪真空处理30min脱腥。经过上述条件处理后的鱼油,色泽为浅黄色、澄清,具有清淡的鱼香味,各项指标均达到了SC/T3502-2000鱼油的一级标准,其中主要物质EPA(16.9%)和DHA(21.2%)。     

石家庄地区牛乳脂肪中脂肪酸成分的分析

选取石家庄地区的牛乳样品，采用OP乳化剂提取出样品中的脂肪，对其进行甲酯化，用填充柱气相色谱法测定了其中的脂肪酸成分；采用面积归一法确定了主要的脂肪酸组成为月桂酸1．415％，豆蔻酸6．735％．十五烷酸0.646％，棕榈酸27．71％，棕榈油酸0．874％，十七烷酸0.46％，硬脂酸17．91％，油酸34．29％．亚油酸4．608％．亚麻酸1．013％，花生酸0．102％(均为质量分数)。     

木薯蚕蛹油中脂肪酸成分分析

采用气相色谱-质谱法(GC-MS)和气相色谱法(GC)分析木薯蚕蛹油中脂肪酸的组分及含量。通过GC-MS定性测定,木薯蚕蛹油中含有11种脂肪酸,通过面积归一法分析。各脂肪酸含量为α-亚麻酸43.41%,棕榈酸21.15%,油酸11.59%,亚油酸10.28%,硬脂酸8.08%,棕榈油酸1.88%,豆蔻酸0.93%,十五碳酸0.31%,反式6-油酸0.24%,月桂酸0.16%和9,10-甲基十九烷酸0.16%;通过GC定量测定,木薯蚕蛹油含α-亚麻酸57.63%,棕榈酸20.62%,油酸7.68%,亚油酸6.28%和硬脂酸3.38%。木薯蚕蛹中含有丰富的不饱和脂肪酸,特别是较多的α-亚麻酸。     

GC-MS分析中药白及中脂肪酸成分

目的气相色谱-质谱联用(GC-MS)分析中药材白及中脂肪酸成分。方法采用石油醚索氏抽提法提取白及中脂肪油,经三氟化硼乙醚甲醇溶液甲酯化处理,用GC-MS测定脂肪酸组成。结果共分离出13个峰,确定了12种脂肪酸成分,主要为亚油酸(9,12-十八碳二烯酸),棕榈酸(十六烷酸),山嵛酸(二十二烷酸),木蜡酸(二十四烷酸),肉豆蔻酸(十四烷酸)等。结论此法操作简单、迅速、灵敏、准确度高,可满足白及药材中脂肪酸成分的分析需要。     

两种不同酯化方法分析荞麦中脂肪酸成分

采用索氏提取法对荞麦油进行了提取,分别采用两种方法进行甲酯化处理,以气相色谱-质谱联用仪进行了分析,对脂肪酸组成和含量进行了比较。结果表明:两种酯化方法分别鉴定出8种脂肪酸,占荞麦油总量的98.64%和99.97%;方法1鉴定出的主要脂肪酸为:棕榈酸占脂肪酸总量的15.92%,亚油酸占脂肪酸总量的30.37%,油酸占脂肪酸总量的35.32%;方法2鉴定出的棕榈酸占脂肪酸总量的35.66%,亚油酸占脂肪酸总量的11.75%,油酸占脂肪酸总量的33.26%。     

野生软枣猕猴桃中脂肪酸成分分析

采用索氏提取法提取辽南地区的野生软枣猕猴桃全果及其籽中脂肪酸。甲酯化处理后,采用气相色谱- 质谱联用(GC-MS)方法分离和鉴定。结果表明：在野生软枣猕猴桃全果中分离鉴定出7 种脂肪酸,分别是棕榈酸(6.66%)、亚油酸(10.57%)、亚麻酸(77.78%)、硬脂酸(3.09%)、10,13- 十八碳二烯酸(0.2%)、11- 二十碳烯酸 (0.8%)、花生酸(0.14%);在野生软枣猕猴桃籽中分离鉴定出4 种脂肪酸,分别是棕榈酸(3.24%)、亚油酸(5.40%)、亚麻酸(42.49%)、硬脂酸(2.39%)。其中亚麻酸的含量最高,分别占77.78% 和42.49%。     

亚麻籽油中脂肪酸成分的GC-MS分析

用无水乙醚提取亚麻籽油，经皂化、甲酯化处理，采用气相色谱-质谱（GC—MS）联用技术对其脂肪酸组成进行了分析和鉴定。共分离鉴定了13种脂肪酸：含有4种饱和脂肪酸，占脂肪酸总量的12．71％，其中以十六烷酸（7．31％）、十八烷酸（5．04％）为主；含有9种不饱和脂肪酸，占脂肪酸总量的87．1％，其中以亚麻酸（49．05％）、油酸（22．34％）、亚油酸（13．73％）为主。可见作为一种富含w-3和w-6不饱和脂肪酸的功能性油脂，亚麻籽油具有营养保健和药疗功效。     

芝麻中脂肪酸成分的GC分析

选取黑芝麻和白芝麻两个品种,研碎,用甲醇和氯仿提取脂肪,将提出的脂肪甲基化,并用TLC分离纯化甲基酯,纯化的甲基酯通过100m×0.25mm的GC毛细管柱来测定脂类中脂肪酸组成.结果显示:芝麻中主要含有10种脂肪酸,不饱和脂肪酸为主要成分,其中单不饱和脂肪酸的含量分别为38.888%,40.041%,主要为油酸,其含量分别为38.616%,39.759%;多不饱和脂肪酸含量分别为44.695%,44.545%,主要为亚油酸,其含量分别为44.026%,44.119%.同时还发现有少量的共轭亚油酸的存在.分析表明,黑芝麻和白芝麻的脂肪酸组成相近.     

不同产地牡丹籽油脂肪酸成分检测

不同产地牡丹籽以超声波辅助提取,氢氧化钠甲醇酯交换法甲酯化后.用气相色谱技术对牡丹籽油中不饱和脂肪酸组分进行定量分析,用气相色谱一质谱联用技术对不同产地牡丹籽油中脂肪酸成分进行定性验证     

羊乳脂肪中脂肪酸成分的气相色谱分析

选取广州花都地区的羊乳样品,采用OP乳化剂提取出样品中的脂肪,对其进行甲醋化,用填充柱气相色谱法测定了其中的脂肪酸成分;采用面积归-法确定了主要的脂肪酸组成为乙酸9.48%,丁酸2.08%,已酸1.67%,辛酸3.62%,癸酸4.26%,月桂酸2.34%,豆蔻酸7.42%,十五烷酸0.65%,棕榈酸22.32%,棕榈油酸0.87%,硬脂酸10.04%,油酸23.78%,亚油酸6.54%,亚麻酸2.53%,其他脂肪酸2.30%（均为质量分数）,饱和脂肪酸和不饱和脂肪酸之比为1.39：1.     

核桃果实各部位脂肪酸的组成与含量分析

为评价核桃的营养价值并探讨核桃果实各部位的脂肪酸组成结构，通过气相色谱/质谱联用技术（GC/MS）对桃核各部位（核壳、核仁、种皮及青果皮）的脂肪酸成分进行比较分析，鉴定出亚油酸、亚麻酸、棕榈酸、硬脂酸、油酸等14种脂肪酸成分及其在核桃各部分中的相对含量。分析了桃核各组成部分中不饱和脂肪酸与饱和脂肪酸所占比例及营养价值。     

TUDIES ON THE FATTY ACID COMPOSITION OF HOP EXTRACT

Studies on fatty acids composition of hop extract obtained from Vurtenberg hop by extraction with a threecomponent mixture was carried out. It has been established that the content of fatty acids in hop extract is 0.3% ±5%. Fatty acids composition was determined by Gas-chromatographic analysis. The presence of the following unsaturated fatty acids has been proven: C_16:1; C_18:1; C_18:2; C_18:3; C_20:1 which represent about 40% of the general content of fatty acids in the extract.     

德昌水牛乳脂肪酸组成的气相色谱—质谱分析

分析德昌水牛及其杂交后代乳脂肪酸的组成特点.采集德昌水牛及其与尼里拉菲水牛的F1代常乳样品,提取脂肪后进行甲酯化,用气相色谱-质谱联用法测定脂肪酸组成.结果显示,德昌水牛及其F1代乳中的主要脂肪酸为肉豆蔻酸、棕榈酸、油酸、硬脂酸,乳中肉豆蔻酸、棕榈酸比例显著低于F1代,而硬脂酸、油酸比例显著高于F1代.德昌水牛乳脂肪酸组成与牛乳、牦牛乳相比存在一些差异.     

温度对海洋微藻生长及脂肪酸组成的影响

研究了不同温度下,三角褐指藻和等鞭金藻生长及脂肪酸组成.结果表明,三角褐指藻的最适生长温度为20℃,而等鞭金藻的最适生长温度为25℃.无论是三角褐指藻的EPA还是等鞭金藻的DHA,均随着培养温度的升高而下降.低温有利于三角褐指藻积累EPA和PUFAs,但PUFAs含量（W/W）在10-20℃之间差异不显著（P＞0.05）.虽然等鞭金藻DHA含量随着温度的上升而下降,但PUFAs在20℃时含量（W/W）最高,为10.5%.不同海洋微藻不仅具有不同的生长温度,且最适PUFAs合成的温度也不同.     

抽油烟机回收油的脂肪酸组成变化特征研究

食用油在烹饪过程中挥发,会在抽油烟机系统中凝结。分别以花生油、葵花籽油、茶籽油、玉米油和调和油5种不同植物油为食用油进行烹饪试验,收集经抽油烟机系统凝结的油脂。通过测定抽油烟机回收油和相应未烹饪油的脂肪酸,来分析回收油脂肪酸组成变化特征。结果表明,回收油的脂肪酸种类和含量显著性差别于未烹饪油(P0.05)。回收油增加了C14∶0、C16∶1n7c短碳链脂肪酸,其饱和脂肪酸的含量增加了,不饱和脂肪酸含量减少了,其脂肪酸不饱和度明显降低,仅是未烹饪油的50%~61%。回收油中短碳链脂肪酸有增加的趋势,长碳链脂肪酸含量有减少的趋势,而且新增了食用油本底很少或没有的C18∶3n3c和EPA脂肪酸。回收油的品质也开始变化,有些回收油的脂肪酸已严重偏离了正常植物油的特征值。因此,抽油烟机回收油已不适合再食用,烹饪过程中应降低烹饪温度以减少食用油的变质。     

LONG-CHAIN FATTY ACID COMPOSITION AS A CRITERION FOR YEAST DISTINCTION IN THE BREWING INDUSTRY

The diversity of yeasts isolated from brewing plants and its role on beer quality makes yeast distinction a major concern in industrial microbiological control. Several approaches have been tried to develop rapid and simple methods to perform such tasks. Among these, stands the utilization of long-chain fatty acid composition of total yeast biomass. In this paper results are reported showing the potential of this technique to characterize yeast flora isolated from industrial plants. Fatty acid profiles of brewing species are clearly differentiated from those of non-Saccharomyces strains using statistical data treatment by principal component analysis (PCA). Distinction between brewing and wild strains of Saccharomyces spp. was not apparent. In comparison, fatty acid profiling showed higher discriminating ability than growth on lysine medium for non-Saccharomyces strains. For distinction of S. cerevisiae var. diastaticus from other Saccharomyces strains, growth on starch medium showed to be necessary.     

THE VALUE OF LONG-CHAIN FATTY ACID COMPOSITION IN THE IDENTIFICATION OF SOME BREWERY YEASTS

The cellular long-chain fatty acids of 72 strains representing 29 species of brewery yeasts were extracted by saponification and analysed as methyl esters by gas chromatography. With this method, it was possible to distinguish between Saccharomyces cerevisiae and five other groups from the brewery industry, only four hours after they were obtained from 48 h old cultures under standard conditions. This compares favourably with the 7 to 10 days for conventional methods.     

粮食脂肪酸值测定方法的研究进展

脂肪酸值是粮食储存品质的重要指标。本文简要介绍提取粮食游离脂肪酸的各种溶剂,对滴定法、比色法和色谱法等粮食脂肪酸值测定方法的优缺点及其研究进展也作了探讨。     

SEASONAL VARIATIONS IN FATTY ACID COMPOSITION OF OIL IN DEVELOPING COCONUT

ABSTRACT

Studies on seasonal variation in oil and fatty acid profile of developing solid endosperm of two cultivars, West Coast Tall (WCT) and Chowghat Orange Dwarf (COD), and their hybrids indicated that oil percentage increased from 30% in 6‐month‐old nuts to 63% in matured nuts (12 months old). Nuts sampled during July from different levels of maturity had high oil percentage and followed by those sampled during April, October and January. During nut development to maturity, the percentages and contents of medium and long chain saturated fatty acids increased except that of palmitic and myristic acids. Concentration of long chain unsaturated fatty acids (LCUFAs) in developing coconut kernel were high at 5 and 6 months after fertilization and then decreased toward maturity. The LCUFAs were high in nuts developing during October; consequently, saturated to unsaturated fatty acid ratios were low during October. Results indicated that nuts matured during October had better nutritional quality for human consumption and those matured during January are more suitable for industrial purpose due to higher medium chain fatty acid concentrations.

PRACTICAL APPLICATIONS

Coconut is consumed either as the tender nut (5–6 months after fertilization) or as the kernel from mature nut (12 months after fertilization). Recent technologies of making snowball tender nut use the nuts aged 7–8 months old. Kernel also is consumed in this product. Apart from this, the coconut is being increasingly used for making different kernel‐based value‐added products. This information is useful, as the value‐added products are being developed using different maturities of coconut. Hence, it is of paramount importance that the fatty acid profile of coconut kernel is known in detail for assessing the safety of food consumption from the human health point of view. Apart from this, information on the seasonal variation in fatty acid profile of developing endosperm gives an integrated knowledge so as to optimize the usage of coconut kernel for both human consumption and industrial exploitation.