Conjugated Linoleic Acid and Fatty Acid Composition of Yogurt Produced from Milk of Cows Fed Soy Oil and Conjugated Linoleic Acid

ABSTRACT: Yogurt was processed from milk from Holstein cows whose diets were supplemented with soy oil (5%) and/or conjugated linoleic acids (CLA, 1%) to determine the effect of processing and dietary supplementation on CLA and fatty acid composition. Processing and storage for 7 d did not significantly affect CLA or fatty acid composition. CLA contents of milk and yogurt increased 2.8- and 2-fold by soy oil and CLA supplementation, respectively. Contents of saturated fatty acids decreased and trans -octadecenoic acids increased with the soy-oil-supplementation. The addition of CLA to soy-oil-supplemented diets did not significantly affect the CLA and fatty acid composition of the yogurt.     

功能性调和菜籽油制备及脂肪酸组成分析

以菜籽油、亚麻籽油、青藏高原牦牛酥油为原料,分别按照牦牛酥油∶亚麻籽油∶菜籽油质量比为1∶2∶7(A)、1∶1∶8(B)、2∶1∶7(C)制备调和油,通过单因素试验和正交试验分别确定3种调和油中牦牛酥油溶解率的最佳工艺条件;利用气相色谱-质谱法（gas chromatography-mass spectrometry,GC-MS）分别对3种调和油及其沉淀进行脂肪酸组成分析。结果表明,3种调和油均无异味,酸值、过氧化值均符合国家食用油标准,油脂品质高、稳定性强、不易变质;所有调和油及其沉淀物质共检出脂肪酸44种,单一样品脂肪酸检出种类在39种～44种之间;共检出8种支链脂肪酸,其中,调和油C中支链脂肪酸含量最多,为2.92%;3种调和油中检出的主要脂肪酸为棕榈酸、亚麻酸、亚油酸、油酸,ω-6、ω-3脂肪酸含量的比值在1.29～1.80之间,从营养价值角度出发,调和油A中ω-6脂肪酸和ω-3脂肪酸比值较小,脂肪酸含量的比例更接近1∶1。     

Fatty Acid Profiles of Lipid Depots and Cholesterol Concentration in Muscle Tissue of Finishing Pigs Fed Ractopamine

Ractopamine (RAC) enhances lipolysis and depresses lipogenesis in pigs. We hypothesized that depression of fatty acid (FA) formation from six carbon precursors may enhance enrichment of depot lipids from long chain FA in corn-soybean meal finishing diets. We tested that hypothesis as well as the effect of RAC on muscle cholesterol concentration. Finishing pigs were fed 16% protein corn-soybean diets containing 0 or 20 ppm RAC. RAC feeding had only a minor effect on fatty acid profiles (FAP) of lipid depots of finishing pigs. Adipose tissue lipids of pigs fed RAC had lower 18:0 (wk 4) and higher 18:3 (wk 4) and 18:2 (wk 6) compared to controls. Muscle lipid effects were quite variable. Total cholesterol concentration of muscle was not significantly affected by RAC feeding.     

Yield, Lipid, Cholesterol and Fatty Acid Composition of Spent Hens Fed Full-Fat Oil Seeds and Fish Meal Diets

Yield, proximate and fatty acids composition of white and dark meats and whole carcasses were determined in spent hens fed flax or canola seeds, fish meal and a control diet. Live weights and percent carcass cut-up yield were not affected by the diets fed. However, hens fed flax seed diets contained significantly (P< 0.05) lower levels of cholesterol in the dark meat than the control group. The inclusion of oil seeds, in particular flax seeds in the hens diet, enriched the meats with omega-3 fatty acids (C18:3ω>3; C20:5ω3; C22:5ω3). Omega-3 fatty acids enriched poultry meats from spent hens could be useful in the development of “health oriented” further processed poultry products.     

品种和部位对川味腊肉脂肪氧化及脂肪酸组成的影响

以杂交猪和土猪的背部、腹部、腿部为原料制作川味腊肉,研究不同品种和部位的原料猪肉对川味腊肉脂肪氧化及脂肪酸组成的影响。结果表明:土猪及杂交猪的背部、腹部和腿部腊肉的酸价、过氧化值、硫代巴比妥酸(thiobarbituric acid,TBA)值等氧化特性存在较大差异;脂肪含量在25.98%~62.27%之间;棕榈酸(C_(16:0))、硬脂酸(C_(18:0))、油酸(C_(18:1))、亚油酸(C_(18:2))、花生一烯酸(C_(20:1))含量较高;同一部位的土猪和杂交猪腊肉的油酸含量差异显著(P0.05),不同品种和部位的腊肉样品中硬脂酸、花生一烯酸和亚油酸含量均差异显著(P0.05)。因此,原料肉的品种和部位对川味腊肉脂肪氧化及脂肪酸组成影响较大。     

Palatase 20,000L催化对黄油脂肪酸和风味特征的影响

研究了脂肪酶Palatase20,000 L催化对黄油脂肪酸和风味物质的影响。采用薄层层析(TLC)和气相色谱(GC)相结合分析黄油及其酶解物的脂肪酸,采用顶空固相微萃取-气相-质谱(SPME-GC-MS)分析风味物质。Palatase 20,000 L脂肪酶催化黄油显著改变了脂肪酸的组成,促进了风味物质(特别是主要风味物质:辛酸和癸酸)的释放(P<0.05)。结果表明,Palatase 20,000 L脂肪酶催化改变了黄油脂肪酸和风味物质的种类和含量。因此,Palatase20,000 L脂肪酶催化能够提高黄油的营养价值和应用领域。     

PaIatase 20，000L催化对黄油脂肪酸和风味特征的影响

研究了脂肪酶Palatase20,000L催化对黄油脂肪酸和风殊物质的影响。采用薄层层析（TLC）和气相色谱（GC）井目结合分析黄油及其酶解物的脂肪酸,采用顶空固相微萃取-气相-质谱（SPME-GC-MS）分析风味物质。Palatase20,000L脂肪酶催化黄油显著改变了脂肪酸的组成,促进了风味物质（特别是主要风味物质：辛酸和癸酸）的释放佃〈0．05）。结果表明,Palatase20,000L脂肪酶催化改变了黄油脂肪酸和风味物质的种类和含量。因此,Palatase20,000L脂肪酶催化能够提高黄油的营养价值和应用领域。     

核桃油脂理化特性与脂肪酸成分的研究

对核桃油脂理化指标、脂肪酸含量进行测定,结果表明随着贮藏期延长,种仁酸败严重,酸价、丙二醛含量增高,碘价下降;油脂理化指标与不饱和脂肪酸含量间存在明显的相关性,油酸含量与碘价极显著负相关,亚油酸含量与碘价极显著正相关,亚麻酸含量与碘价显著正相关.     

Fatty Acid Composition of Lean and Fat Tissue of Swine Fed Various Dietary Levels of Sunflower Seed

Two replicates of 24 pigs each were divided into four treatment groups on the basis of weight and sex. Treatment 1 was a typical barley-soybean meal (SBM) diet. Sunflower seed was substituted for barley-SBM at the levels of 13, 26, and 39% of the diet. Linoleic acid ranged from a low of 7.5% in treatment 1 for intramuscular fat to a high of 54.2% in treatment 4 for inner backfat. Dietary treatments resulted in decreases in both saturated (myristic, palmitic, and stearic) and unsaturated fatty acids (palmitoleic, oleic, and linolenic) at all locations but were not always significant. Because of deleterious carcass effects, diets for growing-finishing swine should contain less than 13% sunflower seed (oil varieties).     

金枪鱼乳化液中脂肪酸提取及组成分析

金枪鱼在加工过程中产生大量乳化液,严重影响产品的外观和风味。以脂肪酸提取率为指标,利用动物蛋白水解酶对乳化液进行处理并对提取脂肪酸的工艺条件进行了研究。结果表明,最佳酶解条件为:加酶量400 U/g,反应时间4 h,pH7.5,固液比1︰0.5。应用气相色谱分析所提脂肪酸的组成,其中饱和脂肪酸含量约为38%,不饱和脂肪酸约为60%。多不饱和脂肪酸(PUFA)的含量达32.80%,其中C20:5(EPA)和C22:6(DHA)的含量分别为8.32%和18.46%。该脂肪酸澄清透明呈淡黄色,略带鱼腥味,各项理化指标均达到SC/T3502-2000标准的鱼油一级要求,是一种潜在的功能性脂肪酸资源。     

鲟鱼卵脂质的提取及脂肪酸组成分析

以西伯利亚鲟鱼卵为原料,比较不同提取方法对鲟鱼卵脂质提取率、脂肪酸及脂质组成的影响。采用索氏提取、酶辅助有机溶剂和超临界CO2三种不同的方法提取鲟鱼卵中的脂质,并分析鲟鱼卵脂肪酸组成及脂质组成。结果显示,不同提取方法对所得到的鲟鱼卵脂质的提取率和脂肪酸的相对含量有显著的影响（P＜0.05）,对鲟鱼卵脂质的脂肪酸种类和脂质组成没有显著影响（P＞0.05）。索氏提取法的提取率为（23.71±1.82）%,中性蛋白酶酶解辅助有机溶剂法的提取率为（15.47±1.21）%,超临界CO2萃取法的提取率为（10.43±2.16）%。鲟鱼卵脂质中含有17 种脂肪酸,包括6 种饱和脂肪酸,4 种单不饱和脂肪酸,7 种多不饱和脂肪酸,其中总不饱和脂肪酸含量达到70%以上,多不饱和脂肪酸含量达到17%以上。不同提取方法提取鲟鱼卵脂质中均含有甘油三酯、胆固醇、极性脂质,其中甘油三酯相对含量达到89%以上。     

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。     

母乳及婴幼儿配方奶粉中脂肪酸的组成及分布特点

母乳是婴幼儿成长最自然、最安全、最理想的食品,是婴幼儿营养的最佳来源。近年来,国内外对母乳脂肪酸的研究逐渐增多,不仅关注其中的长链多不饱和脂肪酸对婴幼儿生长发育的功能性质,并逐渐意识到母乳中甘油三酯独特的组成特点,尤其是母乳脂肪酸在甘油三酯中的位置分布对婴幼儿消化吸收具有重要影响。本文对母乳及婴幼儿配方奶粉中乳脂的组成特点进行综述并提出一些参考建议,旨在为婴幼儿配方奶粉生产企业提供一定的指导。     

煎炸猪油掺杂比例对猪油低场核磁共振弛豫特性及脂肪酸组成的影响

研究不同比例煎炸猪油掺入食用猪油样品的低场核磁共振（low field-nuclear magnetic resonance,LF-NMR）弛豫特性及脂肪酸组成,并分析了二者间的相关性。结果表明：随着煎炸猪油掺杂比例的增加,猪油样品的T21峰起始时间显著减小（P＜0.05）、峰面积比例S21和S22/S23线性增加（R2＞0.968 1）,S22的增长规律符合二项式关系（R2=0.988 6）,峰面积比例S23、单组分弛豫时间T2W、不饱和脂肪酸C18∶1＋C18∶2的含量及不饱和脂肪酸含量/饱和脂肪酸含量（相对不饱和度）均线性降低（R2＞0.956 2）,而T22峰起始时间呈阶梯下降趋势,T23峰起始时间与掺杂比例间的规律性不明显。此外,样品的棕榈油酸C16∶1、棕榈酸C16∶0、亚油酸C18∶2、硬脂酸C18∶0、C18∶1+C18∶2含量及相对不饱和度与LF-NMR弛豫特性S21、T21、S22、T23、T2W存在良好的相关性（R2为0.942～0.995）。研究表明可通过样品的LF-NMR弛豫特性有效反映脂肪酸组成和含量的变化,并对煎炸猪油掺杂比例进行预测。     

基于函数拟合碘值及脂肪酸成分配制功能性复合油的研究

为解决红花籽亚麻籽多不饱和脂肪酸复合油(以亚麻籽油制备的游离多不饱和脂肪酸与红花籽油复配, LA∶ALA=1∶1～2)在实际生产中难以按功能需求的脂肪酸比例快速简便而准确复配的难题,本研究将碘值与脂肪酸GC-MS成分分析结合,应用"连续函数求和原理"和"复合函数连续定理"制定红花籽亚麻籽多不饱和脂肪酸复合油的"碘值-脂肪酸复配标曲",再选取LA∶ALA任意值,利用所制定的标曲复配制备相应的复合油,利用GC-MS检测和碘值检测验证,证实所制定的标曲实用可行,基于"连续函数求和原理"和"复合函数连续定理"函数拟合碘值及脂肪酸组分分析,制定相应的碘值-脂肪酸复配标曲,可用于多元不饱和脂肪酸油脂的快速且脂肪酸比例准确的复配。     

Effect of Breed on Fatty Acid Composition and Lipogenic Enzyme Abundance in the Subcutaneous Adipose Tissue of Pigs

This study investigated the role of lipogenic enzyme expression in breed‐specific fat deposition in pigs. Objectives: (i) determine effect of breed on the relative abundance of the key lipogenic enzymes stearoyl‐CoA desaturase (SCD), delta‐6 desaturase (Δ6D), and fatty acid synthase (FAS) in pig subcutaneous adipose tissue. (ii) Investigate breed‐specific relationships between lipogenic enzyme abundance and fatty acid composition. Large White × Piétrain, Piétrain, and Duroc × Piétrain pigs were used. Expression of SCD, Δ6D, and FAS was analyzed by Western blotting. Fatty acid composition was determined by gas chromatography. FAS protein in Large White × Piétrain pigs was similar to the Piétrain breed, but was significantly higher than Duroc × Piétrain. A positive relationship was found between FAS abundance and the saturated fatty acids (SFAs), for Large White × Piétrain pigs, but not for the other breeds. Δ6D was significantly higher in Large White × Piétrain compared with Duroc × Piétrain and Piétrain. This was accompanied by significantly higher total n?3 poly‐unsaturated fatty acids (PUFAs) in the Large White × Piétrain when compared to the other breeds. Conclusions: (i) increased subcutaneous adipose tissue SFA content in Large White × Piétrain pigs (but not Piétrain and Duroc × Piétrain) is related to increased abundance of FAS protein; (ii) high n?3 PUFA content in Large White × Piétrain pigs is related to activation of Δ6D protein synthesis; (iii) SCD and Δ6D abundance does not contribute to between‐breed differences in MUFA and n?6 PUFA content of pig subcutaneous adipose tissue.     

海鞘中产油脂共附生真菌的筛选及脂肪酸组成成分分析

从20株海鞘共附生真菌中筛选产油脂菌。采用苏丹混合溶液染色法初筛,摇瓶复筛,酸热法提取油脂油脂,气相色谱-质谱联用法（GC-MS）测定其脂肪酸组成,形态学观察结合分子生物学鉴定产油脂真菌。结果表明：经初筛和复筛得到3株油脂含量均达20.00%以上的菌株,分别为菌株P2-18、P1-17和P2-4,脂肪酸组成分析不饱和脂肪酸分别占其脂肪酸组成的93.90%、55.80%和65.00%。其中γ-C18:3(γ)亚麻酸、C16:1棕榈一稀酸和C18:1油酸含量最多。P2-4含23.2%的γ-C18:3(γ)亚麻酸,约占其不饱和脂肪酸的24.50%。3株真菌经形态学鉴定,结合分子生物学ITS区序列鉴定,菌株P2-4为桔青霉（Penicillium citrinum）,P1-17为青霉属（Penicillium sp. 12 BRO-2013）,P2-18为土曲霉（Aspergillus terreus）。因此,该海鞘共附生真菌具备开发微生物功能性油脂的潜力,具有良好的开发应用前景,值得进一步研究。