单不饱和脂肪酸的功能特性

单不饱和脂肪酸(MUFA)作为膳食脂肪酸中的一类，具有特殊的生理功能和独特的物理、化学特性，在日常饮食中也与我们接触密切。近年来，不少高校对单不饱和脂肪酸的功能性展开了新的研究。本文就单不饱和脂肪酸的的种类、来源，物理、化学和生理功能特性作了介绍。     

蛋黄不饱和脂肪酸的生理功能的研究进展

蛋黄因其独特而丰富的营养特性而备受关注,不饱和脂肪酸又由于具有预防糖尿病、抗炎症、抗氧化性等生理功能而受到各国研究者的重视,蛋黄中的不饱和脂肪酸已经成为食品领域的研究热点。该文就蛋黄中单不饱和脂肪酸(MUFAs)和多不饱和脂肪酸(PUFAs)的生理功能进行综述,阐述蛋黄不饱和脂肪酸具有提高视力和保护精子质量等生理功能,以期使蛋黄不饱和脂肪酸在医疗、保健和食品中得到更广泛的应用,并为相关领域研究者提供参考。     

肉类脂肪酸的营养与免疫调节作用

综述了肉类脂肪中饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸及共轭多不饱和脂肪酸构成特性及其对人体的营养与健康功能,以及肉类脂肪中三酰甘油、磷脂、固醇类等的免疫调节作用与疾病的关系。     

单不饱和脂肪酸与冠心病的关系

目的综述单不饱和脂肪酸与冠心病的关系。方法对国内外有代表性的文献加以归纳总结。结果与结论单不饱和脂肪酸通过对凝血功能、血脂和血压的影响,可降低冠心病的发病危险性。     

生物酶法合成单甘酯的研究进展

生物酶法合成单甘酯具有能耗低、产率高、产品安全性能高、反应时间短和无环境污染问题等优点。本文综述了生物酶法合成单甘酯的方法、反应体系和分离提纯方法,同时也介绍了单甘酯在食品中的应用,特别介绍了具有更好乳化性和抗菌性等特性的高含量不饱和脂肪酸单甘酯在食品中的应用。     

爱恨交织话脂肪(二)

正脂肪怎么吃上期让大家了解了脂肪,我们就知道含饱和脂肪(酸)和反式脂肪(酸)的油要少吃,尽量选择含不饱和脂肪(酸)的油。不饱和脂肪酸分为单不饱和脂肪酸和多不饱和脂肪酸。植物油中含单不饱和脂肪酸的典范就是橄榄油、茶油,有助于降低血糖、调节血脂、降低胆固醇。多不饱和脂肪是人体自身不     

食品添加剂不饱和脂肪酸单甘酯的测定与表征

建立了食品添加剂不饱和脂肪酸单甘酯定性表征和定量分析方法。采用气相色谱-质谱法对不饱和脂肪酸单甘酯和甘油进行定性、定量分析,结果表明:不饱和脂肪酸单甘酯主要含有5种脂肪酸,即十六烷酸(棕榈酸)、十八碳二烯酸(亚油酸)、十八碳烯酸(油酸)、十八烷酸(硬脂酸)、二十二烷酸(山嵛酸)。     

不饱和脂肪酸单甘油酯对大豆蛋白饮料稳定性的影响

不饱和脂肪酸单甘油酯具有优良的乳化分散性,兼具保健功能。以硬脂酸单甘油酯作为对照,采用分光光度法测定了油酸单甘油酯、亚油酸单甘油酯的乳化性能。脂肪酸单甘油酯作为乳化剂应用于大豆蛋白饮料配方,采用多重光散射法和离心分析法研究了乳化剂对大豆蛋白饮料分散体系稳定性的影响。结果表明:不饱和脂肪酸单甘油酯的乳化性能优于硬脂酸单甘油酯;添加单一乳化剂时,油酸单甘油酯及亚油酸单甘油酯的乳化稳定效果优于硬脂酸单甘油酯,不饱和脂肪酸单甘油酯的添加量对大豆蛋白饮料的稳定性影响不明显;油酸单甘油酯与蔗糖酯复配使用,质量比为1∶1和2∶1时,大豆蛋白饮料分散体系的稳定性较佳,且优于单独添加油酸单甘油酯时的稳定性。     

脂肪酸的营养功能

简述饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸的营养功能。     

小球藻不饱和脂肪酸碱提法工艺优化及其品质分析

本论文采用直接碱提法对小球藻油脂不饱和脂肪酸进行提取,在单因素试验的基础上进一步通过响应面试验对提取工艺进行优化。并以大豆油为参照,对小球藻的不饱和脂肪酸组成进行了测定。此外在大豆油中分别添加了不同浓度的小球藻不饱和脂肪酸并对其过氧化值和酸价等油脂品质特性指标进行分析。结果表明,小球藻不饱和脂肪酸的最佳提取条件为提取料液比1:25（g/mL）、提取温度50 ℃、提取时间60 min,在此工艺条件下小球藻不饱和脂肪酸得率达3.15±0.045%;小球藻不饱和脂肪酸的主要成分依次为亚油酸（62.96±0.86）%、棕榈油酸（12.14±0.025）%、棕榈酸（9.88±0.068）%、油酸（8.62±0.037）%,并富含其他多种脂肪酸;在大豆油中添加小球藻不饱和脂肪酸会提高油脂的过氧化值和酸价,但过氧化值和酸价的升高均在合理范围内,对油脂的品质无明显负面影响。     

厦门白姑鱼腌制加工过程中的脂肪酸变化分析

探讨厦门白姑鱼（Argyrosomus amoyensis）腌制加工过程中的脂肪酸的变化,并结合脂肪氧化相关指标：过氧化值（peroxide value,POV）及硫代巴比妥酸反应物（thiobarbituric acid reactive substance,TBARS）值,确定脂肪氧化对脂肪酸组成的影响。从腌制加工的7 个关键工序中取样,采用气相色谱-质谱联用法分析脂肪酸,同时考察POV及TBARS值。结果表明：厦门白姑鱼原料含26.41%的饱和脂肪酸（saturated fatty acids,SFA）、20.26%的单不饱和脂肪酸（monounsaturated fatty acids,MUFA）和53.33%的多不饱和脂肪酸（polyunsaturated fatty acids,PUFA）,共24 种,必需脂肪酸占12.49%,二十碳五烯酸（eicosapentaenoic acid,EPA）和二十二碳六烯酸（docosahexaenoicacid,DHA）占40.70%。在腌制加工中,SFA含量显著增加,MUFA含量和PUFA含量显著降低（P＜0.05）。POV和TBARS值都呈现了先增后减的趋势,分别在烘干1 d和3 d出现峰值。相关性分析表明,SFA与MUFA呈显著负相关（P＜0.05）,与PUFA呈极显著负相关（P＜0.01）,MUFA和PUFA没有相关性;SFA与POV和TBARS值呈现显著正相关（P＜0.05）,而PUFA与POV和TBARS值分别呈显著（P＜0.05）和极显著负相关（P＜0.01）。因此,厦门白姑鱼脂肪酸种类多,含有丰富的不饱和脂肪酸,腌制加工过程对主要8 种脂肪酸有显著影响,脂肪的氧化使SFA含量增加,同时使PUFA含量降低,PUFA更容易发生氧化。     

GC-MS法分析蚕蛾油与蚕蛹油的脂肪酸组成

采用超临界CO2 萃取雄蚕蛾与蚕蛹中的油脂,经甲酯化处理用气相色谱- 质谱联用仪进行分析,在雄蚕蛾油中分离鉴定出15 种脂肪酸,含量最高的是α- 亚麻酸(36.71%),其中直链饱和脂肪酸(SFA)54.52%;单不饱和脂肪酸(MUFA)6.89%;多不饱和脂肪酸(PUFA)38.63%。在蚕蛹油中共分离鉴定出14 种脂肪酸成分,含量最高的是亚油酸(39.03%),其次是α- 亚麻酸(33.22%),其中直链饱和脂肪酸(SFA)占25.73%;单不饱和脂肪酸(MUFA)占2.12%;多不饱和脂肪酸(PUFA)占72.25%。     

Fatty acid composition and oxidative susceptibility of fresh loin and liver from pigs fed conjugated linoleic acid in combination with monounsaturated fatty acids

Three levels (0%, 1% and 2%) of conjugated linoleic acid (CLA) were combined with two levels of monounsaturated fatty acids (MUFA) (low: 19% and high: 39%) for pig feeding. The fatty acid profile of neutral lipids (NL) and polar lipids (PL) of loin and liver and their oxidative susceptibility were studied. A dose-dependent enrichment in cis-9, trans-11 CLA and trans-10, cis-12 CLA in NL and PL of loin and liver was obtained. This effect was independent of the MUFA supplementation (except for NL of loin in which the CLA accumulation was higher at high MUFA levels). Regardless of the MUFA supplementation, dietary CLA increased the ratio of saturated fatty acids (SFA) to unsaturated fatty acids in both tissues and lipid fractions. The interaction between CLA and MUFA affected the SFA and polyunsaturated fatty acids contents of PL from loin. Regardless of the MUFA level of the diets, CLA supplementation decreased the induced peroxidation values in liver and did not change those of loin.     

Endogenous production of n-3 and n-6 fatty acids in mammalian cells

Polyunsaturated fatty acids (PUFA) are important components of mammalian diets, and the beneficial effects of n-3 PUFA on human development and cardiovascular health have been well documented. Caenorhabditis elegans is one of the few animals known to be able to produce linoleic (LA, 18:2n-6) and alpha-linolenic (ALA, 18:3n-3) essential fatty acids. These essential PUFA are generated by the action of desaturases that successively direct the conversion of monounsaturated fatty acids (MUFA) to PUFA. The cDNA coding sequences of the C. elegans Delta(12) and n-3 fatty acid desaturases were each placed under the control of separate constitutive eukaryotic promoters and simultaneously introduced into HC11 mouse mammary epithelial cells by adenoviral transduction. Phospholipids from transduced cells showed a significant decrease in the ratios of both MUFA:PUFA and n-6:n-3 fatty acids relative to control cultures. The fatty acid profile of transduced cellular phospholipids revealed significant decreases in MUFA and arachidonic acid (20:4n-6), and increases in LA, ALA, and eicosapentaenoic acid (20:5n-3). The fatty acid composition of triacylglycerols derived from transduced cells was similarly, but less dramatically, affected. These results demonstrate the functionality of C. elegans fatty acid desaturase enzymes in mammalian cells. Expression of these desaturases in livestock might act to counterbalance the saturating effect that rumen microbial biohydrogenation has on the fatty acid profile of ruminant products, and allow for the development of novel, land-based dietary sources of n-3 PUFA.     

Effect of dietary conjugated linoleic acid in combination with monounsaturated fatty acids on the meat composition and quality traits of dry-cured loin

Three levels (0%, 1% and 2%) of an enriched conjugated linoleic acid oil (CLA) were combined with two levels of monounsaturated fatty acids (MUFA) (low −19% average and high −39% average) for pig feeding. Composition, weight losses, lipid oxidation (thiobarbituric acid test, TBARs), change in the fatty acid content of the lipid fractions and sensory analysis of dry-cured loin as affected by dietary CLA, MUFA and CLA × MUFA interaction were studied. CLA and CLA × MUFA did not affect moisture and intramuscular fat content of dry-cured loin, weight losses during the processing, changes in the content of most fatty acids from lipid fractions and sensory traits. CLA and MUFA supplementation led to lower TBARs values (1.3 mg MDA/kg sample for 0% CLA and 0.9 mg MDA/kg sample for 2% CLA; 1.2 mg MDA/kg sample for low MUFA diets and 0.9 mg MDA/kg sample for high MUFA diets), the highest TBARs values being detected for 0% CLA-low MUFA diets [1.5 mg MDA/kg sample]. The combination of dietary CLA with different MUFA levels in pig diets did not affect most composition and quality traits of dry-cured loin. Dietary CLA and MUFA seemed to lead to lower lipid oxidation in this product.     

澳洲美利奴羊肉脂肪酸组成

选择3 只澳洲美利奴羔羊的背最长肌、臀肌及臂三头肌，利用气相色谱-质谱联用技术对其脂肪酸含量进行测定及分类探讨。结果表明：澳洲美利奴羊肉中共含有脂肪酸35 种，其中C15:1、C16:0、C17:1、C18:0、C18:1 n-9c脂肪酸含量较高，3 个部位肌肉中：不饱和脂肪酸含量＞饱和脂肪酸含量＞单不饱和脂肪酸含量＞多不饱和脂肪酸含量，且每个部位肌肉中单不饱和脂肪酸含量比多不饱和脂肪酸含量均高出2～3 倍；n-3脂肪酸亚麻酸甲酯（C18:3 n-3）在臂三头肌中的含量显著高于背最长肌（P＜0.05）；与另外2 个部位相比，臂三头肌总脂肪酸、饱和脂肪酸、不饱和脂肪酸、中链脂肪酸及长链脂肪酸含量均最高；臂三头肌中多不饱和脂肪酸与饱和脂肪酸含量比值最高，背最长肌中最低。     

Composition and estimation of intramuscular and subcutaneous fatty acid composition in Spanish young bulls

Sixty Pirenaica yearling intact bulls were raised and slaughtered at 519±50kg live weight and 371±18 days of age. Fatty acid composition of intramuscular lipids in longissimus dorsi muscle and subcutaneous fat were determined by capillary gas chromatography. Carcass conformation and fatness, carcass weight, ether extractable intramuscular fat percentage, marbling, dorsal fat thickness, and ultrasonic parameters were recorded to study the relationship between these traits and fatty acid profile. Lipids of subcutaneous adipose tissue had higher monounsaturated fatty acids (MUFA) percentage (49% vs. 33%) but lower saturated fatty acids (SFA) (51% vs. 46%) and polyunsaturated fatty acids (PUFA) (16% vs. 5%) percentages than intramuscular fat depots (p<0.001). Fatter carcasses had higher MUFA percentage and lower PUFA percentage (p<0.01) in intramuscular fat. Carcass weight and conformation would contribute to explain the fatty acid profile of subcutaneous fat (p<0.05). Ultrasound readings reflected the effect of fatness on fat composition.     

Fatty acid composition of Celta pig breed as influenced by sex and location of fat in the carcass

BACKGROUND: The influence of sex and location of fat in the carcass on the fatty acid profile of Celta pigs was studied. Twenty pigs (10 castrated males and 10 females) from the Carballina line were used. RESULTS: The fatty acids composition was predominated by monounsaturated fatty acids (MUFA; approximately 48% of total methyl esters), followed by saturated fatty acids (SFA; approximately 40% of total methyl esters) and, finally, polyunsaturated fatty acids (PUFA; approximately 12% of total methyl esters). The sex and location of fat in the carcass showed significant differences in PUFA and SFA content while both factors were not significantly different with respect to MUFA content. Linoleic, linolenic, eicosatrienoic and arachidonic fatty acids showed the largest difference among the three locations (intramuscular, subcutaneous ventral and subcutaneous dorsal) of the fat in the carcass. CONCLUSION: The fatty acid profile that we observed in the fat of the Celta pigs does not differ greatly from those described by other authors in other autochthonous pig breeds. Principal component analysis offered a good separation of the mean samples according to the sex and location of fat of the pigs. Copyright © 2011 Society of Chemical Industry     

四棱豆油脂、脂肪酸、蛋白质、氨基酸的分析

以4 个四棱豆品种的种子为材料,采用索式提取法、毛细管柱测定总脂肪含量及分析各脂肪酸含量;利用凯氏定氮法、全自动氨基酸分析仪测定蛋白质总量及各蛋白氨基酸组成。结果表明,四棱豆种子中油脂总量在20%～22%,主要含有28 种脂肪酸,油酸占单不饱和脂肪酸的90.7%;多不饱和脂肪酸主要为亚油酸、α - 亚麻酸和EPA;饱和脂肪酸平均含量为25.76%,主要为棕榈酸和硬脂酸。蛋白质总量在38% 左右,必需氨基酸含量丰富。     

Determination of the seasonal changes on total fatty acid composition and ω3/ω6 ratios of carp (Cyprinus carpio L.) muscle lipids in Beysehir Lake (Turkey)

The muscle lipid and fatty acid composition of carp, Cyprinus carpio in Beysehir Lake the largest freshwater lake in Turkey, was determined. Polyunsaturated fatty acids (PUFA) of carp, the most abundant fish species in Beysehir Lake, were found to be higher than those of saturated fatty acids (SFA) in spring, summer and autumn and also the monounsaturated fatty acids (MUFA) in spring and summer. Palmitic acid was the major SFA (14.6–16.6%) in all seasons. Oleic acid was identified as the major MUFA (15.1–20.3%). Docosahexaenoic acid (DHA) was the major PUFA in summer and winter, whereas linoleic acid (LA) was the major PUFA in spring and autumn. The percentages of total ω3 fatty acid were higher than those of total ω6 fatty acid in the fatty acid composition of carp in winter. It was shown that the fatty acid composition in the muscle of carp was significantly influenced by feeding period and seasons.