二十二碳六烯酸和花生四烯酸在婴儿配方奶粉中的应用

介绍了乳母中天然存在的两种不饱和脂肪酸二十二碳六烯酸（DHA）和花生四烯酸（AA）在婴儿生长发育中的作用及其在配方奶粉中强化对非母乳喂养婴儿营养的重要性。并介绍了各专家组织对DHA和AA在婴儿配方奶粉中补充的推荐及目前的应用情况。探讨了HDA和AA的两种来源，即天然来源和利用生物技术发酵生产。DHA和AA的天然来源主要是鱼油和蛋黄，而目前商业上大都利用生物技术以薇藻和真菌发酵生产DHA和AA。介绍了生物技术发酵生产DHA和AA的工艺，并讨论了发酵产品在婴儿配方奶粉中应用的安全性。     

花生四烯酸在酸性乳饮料中的应用研究

对花生四烯酸(AA)与二十二碳六烯酸(DHA)微胶囊粉剂在酸性乳饮料中的应用情况进行了研究.结果表明,合适比例的AA与DHA加入到这两种产品中,不会改变产品的口感和风味,不会影响产品的稳定性,也不会影响产品的货架期.     

二十二碳六烯酸(DHA)、二十碳五烯酸(EPA)、亚油酸、亚麻酸和花生四烯酸(AA)在婴幼儿配方奶粉中的测定

建立了气相色谱法同时测定婴幼儿奶粉中的DHA,EPA,亚油酸,亚麻酸和花生四烯酸AA含量的方法。采用色谱柱为脂肪酸型色谱柱DB-23,氢火焰离子化检测器（FID）,优化了色谱条件。结果表明,DHA,EPA,亚油酸,亚麻酸和花生四烯酸AA分离效果很好。DHA的最低检出限为0.02g/L,回收率为99.8%,变异系数为0.88%;EPA的最低检出限为0.01g/L,回收率为94.9%,变异系数为1.01%;亚油酸的最低检出限为0.02g/L,回收率为97.7%,变异系数为0.80%;亚麻酸的最低检出限为0.01g/L,回收率为99.9%,变异系数为0.95%;AA的最低检出限为0.01g/L,回收率为98.9%,变异系数为0.93%。     

二十碳五烯酸和二十二碳六烯酸气相色谱法的测定

介绍了一种快速测定鱼油及乳制品中二十碳五烯酸和二十二碳六烯酸的方法。样品采用三氟化硼-甲醇溶液酯化,用质量分数为5%DEGS+质量分数为1%H3PO4高效色谱柱分离。结果:EPA、DHA的回收率分别为96.2%±3%和95.8%±4%;标准偏差分别为1.68%和2.11%;进样量为1μL,最低检出量分别为2.0×10-8g和6.0×10-8g。该方法酯化简单、快速、完全,色谱分离度高,是测定鱼油制品和乳制品中EPA、DHA的理想方法。     

用豆制品废水发酵生产花生四烯酸和二十碳五烯酸

为探讨用豆制品废水生产花生四烯酸(AA)和二十碳五烯酸(EPA),研究了不同培养时间、碳源浓度、氮源浓度和黄泔水稀释倍数对轮梗霉产这两种脂肪酸的影响.研究结果表明,有利于EPA高产的条件为:黄泔水稀释6倍、添加30g/L碳源、2g/L氮源、培养8 d.有利于AA高产的条件为:黄泔水稀释5倍、添加10g/L碳源、1g/L氮源、培养4 d.最大生物量获得条件和产脂肪酸最佳条件不一致.进一步优化条件,有希望通过豆制品废水获得低成本的EPA和AA产品.     

花生四烯酸在液态奶中的应用研究

阐述了AA液态奶市场开发的必要性及AA在液态奶中的应用。     

花生四烯酸在液态奶中的应用研究

阐述了AA液态奶市场开发的必要性及AA在液态奶中的应用。      

婴幼儿奶粉中亚麻酸、亚油酸、花生四烯酸和二十二碳六烯酸的测定

采用气相色谱法测定婴儿配方乳粉中亚麻酸(LA)、亚油酸(LNA)、花生四烯酸(AA)和二十二碳六烯酸(DHA)含量。试验结果表明:LA、LNA、AA和DHA分离效果较好,得到LA,LNA,AA和DHA的检出限分别为0.057、0.06、0.085和0.25μg/mL;其重复性在0.64%～5.46%之间,回收率在82.1%～105.7%之间。     

花生四烯酸在奶粉中的应用

0引言花生四烯酸(AA)是一种长链多不饱和脂肪酸,在人体内具有重要的生理作用。它可以益智健脑和提高视敏度,对婴幼儿的生长发育以及大脑和视网膜的功能完善具有特别重要的意义,因而被认为是人类早期发育的必需营养素;AA具有改善记忆力和视力、调节血脂和血糖、降低血清胆固醇、预防心血管疾病、辅助抑制肿瘤、预防癌变、神经功能调节等作用。作为一种新型的营养强化剂,AA添加到配方奶粉中,能加快婴幼儿配方奶粉的母乳化进程;上一期我们详细介绍了AA在液态奶中添加及应用工艺,应国内多家奶粉生产企业的要求,本期我们继续介绍AA在配方奶粉…     

花生四烯酸在乳制品中的应用及市场前景

０引言在日常饮食中，牛奶是营养最为全面、最易被吸收的优良营养食品。但牛奶营养的全面和丰富也是相对而言的，仍有一些人体必需的营养素，在牛奶中没有或者含量不足，需要进行必要的补充强化。这一点，对于婴幼儿配方奶粉显得尤为必要，因为它很可能是婴幼儿唯一的营养来源。乳品行业的发展，体现在奶源基地的建设、技术设备水平的提高、产品结构的调整等方面。“九五”期间，国内乳品行业在前两个方面取得了长足的进步，奶源基地建设、奶源管理方面取得突破性进展，技术落后、设备陈旧的状况得到了根本转变。产品结构的调整虽取得了一些…     

气相色谱法测定鱼油中的二十碳五烯酸、 二十二碳六烯酸和二十二碳五烯酸

目的通过优化鱼油中二十碳五烯酸(eicosapentaenoic acid,EPA)、二十二碳六烯酸(docosahexaenoic acid,DHA)和二十二碳五烯酸(docosapentaenoic acid,DPA)的测定条件,建立鱼油中EPA、DHA和DPA气相色谱定量检测分析方法。方法采用正己烷处理样品,经色谱柱(Agilent,Elite-WAX,30 m×0.25 mm,0.25μm)分离鱼油中的EPA、DHA、DPA甲酯标准品,并进行定量检测。结果 EPA浓度在0.36~3.6 mg/m L、DHA浓度在0.37~3.7 mg/m L、DPA浓度在0.16~1.62 mg/m L的范围内与峰面积的线性良好,相关系数r0.999。在80%、100%、120%添加水平下,EPA、DHA和DPA的检出限分别为0.01%、0.03%、0.009%,EPA、DHA和DPA的回收率分别为96.2%、96.4%、95.7%。结论气相色谱法灵敏度高、准确、重现性好,适用于鱼油中EPA、DHA和DPA的含量测定。     

气相色谱法多重检验海豹油中二十碳五烯酸、 二十二碳五烯酸和二十二碳六烯酸方法研究

目的建立多重检验海豹油中二十碳五烯酸(eicosapentaenoic acid,EPA)、二十二碳五烯酸(docosapentenoic acid,DPA)和二十二碳六烯酸(docosahexaenoic acid,DHA)的气相色谱法。方法用氢氧化钾甲醇溶液将样品中EPA、DPA和DHA甲酯化,气相色谱程序升温同时分析3个ω-3多不饱和脂肪酸,分别用外标法和内标法进行定量。结果 3个ω-3多不饱和脂肪酸的外标法定量线性范围为50~5000μg/m L,相关系数均0.999,精密度相对标准偏差均10%,回收率均90%;内标法定量的精密度相对标准偏差均10%,回收率均85%;外标法和内标法对3个ω-3多不饱和脂肪酸的结果比较,CV%均小于10%。结论该方法操作简单快捷,适用于进口海豹油中EPA、DPA和DHA的含量简便和准确的测定。     

Disappearance of docosahexaenoic and eicosapentaenoic acids from cultures of mixed ruminal microorganisms

Previous studies showed conflicting results regarding the ability of ruminal microorganisms to hydrogenate docosahexaenoic acid (C22:6, DHA) and eicosapentaenoic acid (C20:5, EPA). To determine the disappearance of DHA and EPA from mixed ruminal cultures, 2 ruminal in vitro experiments were conducted using graded levels of DHA and EPA. The first experiment examined DHA added at 0, 5, 10, 15, and 20 mg per culture flask. In the second experiment, EPA was added at 0, 5, 10, and 15 mg per culture flask. Docosahexaenoic acid and EPA were incubated in triplicate in 125-mL flasks, and 5 mL of culture contents was taken at 0, 12, and 24 h for fatty acid analysis by gas liquid chromatography. After 24 h of incubation, 4.1, 4.1, 4.0, and 3.3 mg of DHA disappeared from the 5, 10, 15, and 20 mg of DHA cultures, respectively. In the second experiment, 5, 8.3, and 7.1 mg of EPA disappeared after 24 h of incubation for the 5-, 10-, and 15-mg EPA cultures, respectively. Addition of DHA to cultures increased trans-C18:1 fatty acid accumulation by 105, 91, 82, and 74% for the 5, 10-, 15-, and 20-mg cultures, respectively, compared with control. The addition of EPA increased trans-C18:1 fatty acid accumulation by 56, 64, and 55% for the 5-, 10-, and 15-mg EPA cultures, respectively, compared with control. Addition of DHA and EPA to cultures caused a reduction in C18:1 n-9 and C18:2 n-6 biohydrogenation compared with control. Results from these experiments clearly demonstrate the ability of ruminal microorganism to transform DHA and EPA to other fatty acids causing their disappearance from cultures.     

气相色谱法测定鱼油软胶囊中二十碳五烯酸和 二十二碳六烯酸的柱前衍生化方法改进

目的建立柱前衍生-气相色谱法测定保健食品中二十碳五烯酸(eicosapentaenoic acid,EPA)和二十二碳六烯酸(docosahexaenoic acid,DHA)含量的分析方法。方法鱼油软胶囊经皂化后用1%的硫酸-甲醇甲酯化,用气相色谱法测定,FID检测器检测,色谱柱为DB-FFAP(30 m×0.25 mm,0.25μm),进样口温度250℃,检测器温度260℃,柱温215℃,直接进样,外标法定量。结果 EPA和DHA在0.05~5 mg/mL范围内线性良好(r_(EPA)=0.9999,r_(DHA)=0.9999),EPA和DHA的回收率分别为93.1%~102.3%和92.2%~103.9%,EPA和DHA的相对标准偏差均小于3%。结论该方法操作简便、快捷,避免了有毒试剂的使用,定量准确,重现性好,适合大批量样品的快速检测。     

Stability of docosahexaenoic acid and eicosapentaenoic acid in breads after baking and upon storage

Wholemeal bread and white bread were prepared by substituting shortening with refined menhaden fish oil (0.5%, 1.0% and 1.5% w/w). The stability of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were evaluated over 5 days of storage through gas chromatography (GC) analysis along with peroxide and anisidine value determinations. Sensory analysis was also performed by evaluating the fishy flavour, palatability and palatability differences compared to the control bread upon storage. The recoveries of EPA and DHA in breads after baking were 68.7%–72.8% with no further significant changes (P < 0.05) upon storage for both types of breads. Results from GC analyses correlated well with peroxide and anisidine value analyses, which showed relatively low values throughout the storage time. Omega‐3‐fatty acids from Menhaden fish oil can be incorporated into breads by substituting the shortening at a fish oil level of 0.5% (w/w) with acceptable palatability even after a 3‐day storage period.     

Gas-liquid chromatography and the arachidonic acid content of Atlantic food fish

Some gas-liquid chromatographic analyses have overlaps among fatty acid chain lengths. In fish depot fats the resulting peak coincidence of docosenoic acids with arachidonic acid can lead to exaggeration of the indicated content of arachidonic acid in edible flesh of marine fish. Modern wall-coated open-tubular columns also resolve the isomers of docosenoic acid, creating potential further problems in fatty acid identifications. Case histories for Atlantic food fish and recent publications are used to emphasize that only accurate marine fish fatty acid data should be used for dietary fatty acid-blood lipid dietary correlations.     

Anti-obesity effects of conjugated linoleic acid, docosahexaenoic acid, and eicosapentaenoic acid

Obesity has become a prevailing epidemic throughout the globe. Effective therapies for obesity become attracting. Food components with beneficial effects on "weight loss" have caught increasing attentions. Conjugated linoleic acid (CLA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) belong to different families of polyunsaturated fatty acids (PUFA). However, they have similar effects on alleviating obesity and/or preventing from obesity. They influence the balance between energy intake and expenditure; and reduce body weight and/or fat deposition in animal models, but show little effect in healthy human subjects. They inhibit key enzymes responsible for lipid synthesis, such as fatty acid synthase and stearoyl-CoA desaturase-1, enhance lipid oxidation and thermogenesis, and prevent free fatty acids from entering adipocytes for lipogenesis. PUFA also exert suppressive effects on several key factors involved in adipocyte differentiation and fat storage. Despite their similar effects and shared mechanisms, they display differences in the regulation of lipid metabolism. Moreover, DHA and EPA exhibit "anti-obesity" effect as well as improving insulin sensitivity, while CLA induces insulin resistance and fatty liver in most cases. A deeper and more detailed investigation into the complex network of anti-obesity regulatory pathways by different PUFA will improve our understanding of the mechanisms of body weight control and reduce the prevalence of obesity.     

Improved physical stability of docosahexaenoic acid and eicosapentaenoic acid encapsulated using nanoliposome containing α‐tocopherol

This study aimed to develop a nanoliposomal formulation containing α‐tocopherol loaded with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and to characterise the formulation by its physical stability. For this purpose, different nanoliposomal formulations with dipalmitoyl phosphocholine were prepared using a modified thin‐film hydration method and evaluated by particle size, polydispersity index (PDI), transmission electron microscopy, differential scanning calorimetry and determining the encapsulation efficiencies of DHA and EPA. A physical stability study was conducted by investigating the change in the vesicle encapsulation efficiency, particle size, PDI and shape when stored at 4, 30 and 40 °C for 3 months. High encapsulation efficiency of DHA and EPA (89.1% ± 0.6% and 81.9% ± 1.4%) and appropriate particle size (82 ± 0.8 nm) were obtained for liposomes composed of α‐tocopherol. The optimum formulation was stable for 90 days when kept at 4 °C. This study demonstrated that α‐tocopherol had a protective effect on the physical stability of the nanoliposomes containing DHA and EPA.