研发生产富含Omega-3脂肪酸食品是改善民众营养健康状况的重要饮食策略（网络首发、推荐阅读）

Omega-6和Omega-3脂肪酸都是对细胞结构和功能非常重要的必需营养素,但人体不能合成,必须从食物中获得。这两类脂肪酸在代谢和功能上不同,并拮抗调节许多生理和病理过程。因此,Omega-6和Omega-3脂肪酸之间的相对平衡对健康至关重要。然而,现今的饮食中Omega-6过多,而Omega-3过少,导致严重失衡,大多数人体内的Omega-6/Omega-3 脂肪酸比率很高（>10）。许多证据表明,这个失衡是导致现代慢性疾病发生和发展的关键因素。越来越多的实验室及临床研究结果表明,通过增加机体组织中的Omega-3脂肪酸和/或减少Omega-6脂肪酸来均衡Omega-6/Omega-3脂肪酸的比例,对许多危及生命的慢性疾病的防治和促进公众健康都非常有益。因此,开发和生产富含Omega-3脂肪酸的食品应作为每个国家的一项健康重点工程,以平衡必需脂肪酸的摄入,从而改善人们的营养和健康状况。     

新时期国民膳食脂质摄入推荐的几点建议（网络首发、推荐阅读）

随着社会经济水平的快速提高,我国居民膳食结构发生了明显的改变。膳食脂质是膳食结构的重要组成部分,其推荐摄入量对改善居民膳食结构,实现新时期健康中国建设目标的都有着重要影响。对中国居民膳食脂质参考摄入量的修订提出几点建议。（1）我国18岁及以上居民的膳食脂肪供能比可接受范围上限（U-AMDR）是30%E,低于欧盟和北美国家的35%E。有学者建议提高我国成年人膳食脂肪供能比的U-AMDR,但仍缺乏足够的证据,暂不宜做修改。然而,考虑到老年人需要高能量和营养密度膳食的特点,应考虑提高老年人膳食脂肪的U-AMDR。（2）一些研究表明n-6/n-3多不饱和脂肪酸比值（n-6/n-3PUFA）与多种慢性非传染性疾病发生风险密切相关。我国居民膳食中n-6/n-3PUFA比值的平均值达到8.6,在某些人群中甚至更高。因此,建议将膳食中n-6/n-3PUFA比值的推荐值纳入新版膳食脂质参考摄入量推荐中。（3）尽管开展了大量研究,但膳食胆固醇摄入量与心血管疾病等多项慢性疾病发生结局之间的关系仍不明确。我国城市居民平均每日胆固醇摄入量为264.0 mg,农村居民为168.8 mg,处于正常范围。基于目前的研究证据,仍无法针对一般成年人群制订膳食胆固醇摄入限量。对于心脑血管疾病等慢性疾病的患者,建议参考相应疾病指南中膳食胆固醇摄入量的推荐。     

基于CBAM-InceptionV3迁移学习的食品图像分类（网络首发、推荐阅读）

为提高食品图像自动识别分类的准确率,提出一种嵌入通道注意力机制和空间注意力机制的卷积块注意力模块(CBAM)的“开端”第三版(Inception V3)分类模型。将带有图像网络(ImageNet)预训练权重参数的InceptionV3模型拆分后,在每个Inception块后嵌入CBAM模块,再重新组装成新模型,共嵌入11个CBAM模块。将此模型用于经过填充和缩放到299×299像素的Food-101食品图像数据集进行迁移学习,最高准确率达到82.01%。与原始的InceptionV3模型相比,CBAM模块能够有效提升模型的特征提取和分类能力;同时迁移学习与从头开始训练相比也可以大幅提高准确率、缩短训练时间。与其它几类主流卷积神经网络模型进行对比实验,结果表明该模型具有较高的识别准确率,可为食品图像分类识别提供有力支撑。     

不同贮藏环境和时间对大米质量影响的研究（网络首发、推荐阅读）

为研究龙粳31大米在高温高湿普通米桶、高温高湿负压米桶、室温普通米桶和室温负压米桶贮藏期间品质变化的规律,探究贮藏环境和时间对大米质量状况的影响。检测和分析大米外观、脂肪酸值、食味值、直链淀粉、蛋白质、脂肪酸组成和含量、米粉糊化特性等指标,并在贮藏环境和贮藏时间两个维度上对数据进行可视化雷达图分析。结果表明高温高湿和贮藏时间的延长能加速大米品质的劣化,不同贮藏环境和时间对峰值黏度（1 991 ~ 2 859 cP）、最终黏度（2 650 ~ 3 334 cP）、最低黏度（1 459 ~ 2 182 cP）、脂肪酸值（2.74 ~ 32.58 mg/100 g）、油酸（1.12 ~ 1.81 mg/g）、亚油酸（2.68 ~ 3.53 mg/g）和食味值（68.72 ~ 80.30分）等指标具有显著的影响（P < 0.05）。雷达图分析表明,高温高湿普通米桶贮藏大米品质劣化的品质指标主要为脂肪酸值、油酸和亚油酸;高温高湿负压米桶贮藏大米品质劣化的指标主要为峰值黏度和最终黏度;室温普通米桶和室温负压米桶贮藏大米品质劣化的指标为峰值黏度和最低黏度。不同贮藏时间上,峰值黏度和最低黏度呈现出先上升后下降的趋势,脂肪酸值持续升高,油酸和亚油酸含量在贮藏到15天后急剧下降,食味值逐渐降低。综上,短时间（15天）的大米贮藏,负压米桶能更好地保持大米的品质状况;长时间（15天以上）的大米贮藏,普通米桶和负压米桶差异不显著。     

常见亲水胶体对烘焙食品品质影响的研究进展（网络首发、推荐阅读）

亲水胶体具有良好的功能特性,如改善食品的乳化、胶凝、溶解性和质构等特性。在烘焙食品中,亲水胶体用于改善面团、面包和蛋糕特性,提高感官质量以及延长食品货架期。已经有研究报道了亲水胶体在面包、饼干、蛋糕和面食制备中的潜在用途。综述常见的亲水胶体（黄原胶、瓜尔胶、阿拉伯胶、K-卡拉胶、刺梧桐胶、海藻酸盐、甲基纤维素、羧甲基纤维素和羟丙基甲基纤维素）对焙烤食品的流变学、理化、质构以及其它品质特性的影响,亲水胶体的加入使得产品的颜色、外观、风味和整体可接受性显著改善。     

基于棕榈仁油的特医脂肪乳液制备及其对小鼠血脂的影响（网络首发、推荐阅读）

中链甘油三酯是特医脂肪组件的重要组成成分,棕榈仁油是其天然食物来源。为开发基于棕榈仁油的特医脂肪乳液产品,依据《特殊医学用途配方食品通则》《中国居民膳食营养素参考摄入量》等进行脂肪酸均衡型乳液油相配方设计,并分析其脂肪酸组成;以Zeta电位、粒径为指标优化脂肪乳液制备工艺,并对研发产品进行稳定性评价,通过小鼠试验研究其对血清血脂的影响。结果表明,油相不饱和脂肪酸中n–6与n–3比值为5.16±0.05;采用分步乳化法,最佳乳化工艺为乳化速度10 000 r/min,乳化时间20 min, 乳化温度50 ℃;初乳液经高压均质机50 MPa均质三次,121 ℃高压灭菌10 min,在上述条件下制备的脂肪乳液产品质量稳定。动物试验结果表明,该脂肪酸均衡型脂肪乳液具有显著降低小鼠血清甘油三酯（Triglycerides,TG）含量（P<0.01）、降低血清总胆固醇（Total cholesterol,TC）含量（P<0.01）,以及降低低密度脂蛋白胆固醇（Low-density lipoprotein cholesterol,LDL-C）含量（P<0.05）和升高高密度脂蛋白胆固醇（High-density lipoprotein cholesterol,HDL-C）含量（P<0.01）的作用,对于调节血脂水平具有一定意义。     

加工条件及关键组分对烘焙食品品质的影响（网络首发、推荐阅读）

烘焙食品市场规模巨大且保持着高速增长的趋势。原料组成、加工条件等因素的变化都会对烘焙制品品质产生影响,了解影响烘焙食品质量的因素,对高品质烘焙食品的加工和生产具有重要意义。本文综述了发酵条件、加工工艺、原料组成对烘焙食品品质的影响,其中涉及了对特殊营养成分添加或者低糖、无糖等功能型烘焙食品的研究,这些新型烘焙食品更符合当下人们对营养健康饮食理念的追求,以期为高品质烘焙食品的设计和生产提供参考,促进烘焙食品行业的发展和升级。     

基于传质特性研究油种类对煎炸薯条质构的影响（网络首发、推荐阅读）

以\"荷兰十五\"品种的马铃薯和4种食用油为研究对象,考察煎炸过程中油种类对薯条质构、失水吸油动力学常数、水分空间分布、晶体结构以及微观结构的影响。结果表明:棕榈油和米糠油炸制薯条的表面硬度高于其它两种油。水分损失动力学结果表明使用棕榈油炸制薯条的表面水分损失速率最快(0.053 6 s^-),其次是米糠油(0.027 5 s^-),高油酸葵花油最慢(0.021 6 s^-1)。核磁共振影像也证实了这一结果。X-射线衍射结果表明米糠油和棕榈油炸制薯条的淀粉-脂质复合物含量高于其它两种油。扫描电镜结果表明棕榈油和米糠油炸制薯条的表面比其它油更致密。表面失水快、淀粉-脂质复合物含量高以及表面的致密性对薯条质构的增加起到重要的作用。     

亚麻籽油浓度对WP/KGM协同稳定的类蛋黄酱稳定性影响（网络首发、推荐阅读）

针对传统蛋黄酱的高胆固醇、高脂、高热量的问题,以乳清蛋白（whey protein,WP）和魔芋葡甘聚糖（Konjac glucomannan,KGM）代替蛋黄、以亚麻籽油为油相,制备无胆固醇、高ω-3不饱和脂肪酸的类蛋黄酱,并探究亚麻籽油浓度对类蛋黄酱外观、微观粒径与结构、堆叠性、挤出成型等物理稳定性及流变特性的影响。结果表明：随着油相浓度的增加,液滴粒径从30.8μm降低至17.1μm,且液滴的均一性增加;体系中液滴具有良好的分散性,微观结构观察显示液滴间无絮凝现象;油相浓度从40%增加到80%时,类蛋黄酱样品的流变特性从流体性质（40%时,G′G″）,粘度、弹性模量与粘性模量均随着油相浓度的增加而增加,抵抗一定外力作用下形变及变形后恢复原状能力逐渐增强,堆叠性、挤出成型亦随油相浓度的增加而增加。综上,可通过调控类蛋黄酱中亚麻籽油的浓度,制备较低粘度、流动性强的类蛋黄酱（油浓度40%～60%）应用于流动性和分散性要求高的酱汁类调味品中,或制备较高粘度、堆叠性强的的类蛋黄酱（油浓度70%～80）应用于有成型、涂沫要求的调味...     

Past and Present Insights on Alpha-linolenic Acid and the Omega-3 Fatty Acid Family

Alpha-linolenic acid (ALA) is the parent essential fatty acid of the omega-3 family. This family includes docosahexaenoic acid (DHA), which has been conserved in neural signaling systems in the cephalopods, fish, amphibian, reptiles, birds, mammals, primates, and humans. This extreme conservation, in spite of wide genomic changes of over 500 million years, testifies to the uniqueness of this molecule in the brain and affirms the importance of omega-3 fatty acids. While DHA and its close precursor, eicosapentaenoic acids (EPA), have received much attention by the research community, ALA, as the precursor of both, has been considered of little interest. There are many papers on ALA requirements in experimental animals. Unlike humans, rats and mice can readily convert ALA to EPA and DHA, so it is unclear whether the effect is solely due to the conversion products or to ALA itself. The intrinsic role of ALA has yet to be defined. This paper will discuss both recent and historical findings related to this distinctive group of fatty acids, and will highlight the physiological significance of the omega-3 family.     

Omega-6/Omega-3 Essential Fatty Acid Ratio and Chronic Diseases

Several sources of information suggest that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids (EFA) of ∼1 whereas in Western diets the ratio is 15/1-16.7/1. Western diets are deficient in omega-3 fatty acids, and have excessive amounts of omega-6 fatty acids compared with the diet on which human beings evolved and their genetic patterns were established. Excessive amounts of omega-6 polyunsaturated fatty acids (PUFA) and a very high omega-6/omega-3 ratio, as is found in today's Western diets, promote the pathogenesis of many diseases, including cardiovascular disease, cancer, and inflammatory and autoimmune diseases, whereas increased levels of omega-3 PUFA (a lower omega-6/omega-3 ratio), exert suppressive effects. In the secondary prevention of cardiovascular disease, a ratio of 4/1 was associated with a 70% decrease in total mortality. A ratio of 2.5/1 reduced rectal cell proliferation in patients with colorectal cancer, whereas a ratio of 4/1 with the same amount of omega-3 PUFA had no effect. The lower omega-6/omega-3 ratio in women with breast cancer was associated with decreased risk. A ratio of 2-3/1 suppressed inflammation in patients with rheumatoid arthritis, and a ratio of 5/1 had a beneficial effect on patients with asthma, whereas a ratio of 10/1 had adverse consequences. These studies indicate that the optimal ratio may vary with the disease under consideration. This is consistent with the fact that chronic diseases are multigenic and multifactorial. Therefore, it is quite possible that the therapeutic dose of omega-3 fatty acids will depend on the degree of severity of disease resulting from the genetic predisposition. A lower ratio of omega-6/omega-3 fatty acids is more desirable in reducing the risk of many of the chronic diseases of high prevalence in Western societies, as well as in the developing countries, that are being exported to the rest of the world     

Omega-3脂肪酸磷脂制备方法综述

Omega-3脂肪酸磷脂生理功能明确,生物利用度高,在医药、保健品领域具有巨大的市场潜力,其制备方法是全球磷脂研究开发的新动向。综述了目前Omega-3脂肪酸磷脂的制备方法,包括天然提取法、酶促转化法、化学合成法及微生物发酵法。天然提取法是最早获得Omega-3脂肪酸磷脂产品的方法,主要包括溶剂萃取法、膜分离法、柱层析法和盐沉淀法;酶促转化法主要包括酶促酯交换法和酶促酯化法,是目前Omega-3脂肪酸磷脂合成效率最高、最常用的方法;化学合成法及微生物发酵法处于初步研究阶段,为Omega-3脂肪酸磷脂的制备提供了新的思路。     

Proximate and fatty acids composition of the muscles and viscera of Asian catfish (Pangasius bocourti)

The objective of this research was to analyse the distribution pattern of proximate composition and fatty acid profiles in different portions of Asian catfish (Pangasius bocourti). The lipid content was found amongst different portions, ranging from 2.95% to 93.32%, being lowest in the caudal–dorsal portion and highest in the viscera. Protein, moisture and ash contents were inversely proportional to the lipid content amongst the body portion. There was no specific tendency for the changes of each fatty acid composition from the different portions. Monounsaturated fatty acid (MUFA) was the most predominant fatty acid found in all tissues, ranging from 32.7% to 39.9%, followed by saturated fatty acids (SFA) ranged from 30.2% to 36.5% of total fatty acid, whereas the total polyunsaturated fatty acids (PUFA) content was the lowest, ranging from 14.8% to 24.0%. This study revealed that the proximate compositions and fatty acids deposition in Asian catfish varied markedly throughout the body portion.     

功能性油脂的研究进展

概述了油脂对健康的重要作用及目前油脂与健康的研究动态,并综述了功能性油脂和功能性脂肪酸在保健食品方面的一些研究和应用.提示人们应重视油脂食用与健康问题的研究,在吃好的同时应注意吃出营养与健康.     

多不饱和脂肪酸干预脱发症的研究现状及作用机制

脱发症是皮肤科常见疾病之一,发病率较高但临床治疗手段有限。大部分脱发症与毛囊周期的改变有关,而Omega-3及Omega-6多不饱和脂肪酸被证实通过促进或抑制毛囊细胞释放信号分子,从而促进毛囊生长、改善毛囊周期以及促进毛囊的再生。对多不饱和脂肪酸干预脱发症的研究现状及作用机制的国内外相关研究进行综述,期望能够为多不饱和脂肪酸对各类脱发症的治疗提供新思路及深入探讨脱发症的治疗方法及治疗机制提供借鉴,为利用现代分子生物技术改善脱发症提供理论依据。     

Antibacterial activity of eicosapentaenoic acid (EPA) against foodborne and food spoilage microorganisms

Eicosapentaenoic acid (EPA), a long-chain polyunsaturated fatty acid of ω-3 type was evaluated for its antimicrobial action against the range of foodborne and food spoilage pathogens, using agar disc diffusion assay in Luria broth (LB) media. The EPA exhibited antimicrobial activity against Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19166, Staphylococcus aureus ATCC 6538, S. aureus KCTC 1916 and Pseudomonas aeruginosa KCTC 2004. The minimum inhibitory concentrations (MICs) of the EPA against the tested bacterial strains were found in the range of 500-1350 μg/ml using broth dilution method. EPA reduced the viability of S. aureus at 250, 125 and 62.5 μg/ml after 15 min exposure and a steep decline in colony forming units (CFUs) was observed at 125 μg/ml after 30 min exposure, while similar reduction in CFU rate was exhibited by EPA when treated with 62.5 μg/ml after 180 min. EPA also reduced the CFU numbers of P. aeruginosa at all the concentrations used in this study after 15 min exposure. On the other hand, scanning electron microscopy (SEM) study of bacterial cells clearly exhibited the antibacterial effect of EPA as evidenced by the damages found in the outer membrane of the cells when treated with EPA. The results demonstrated that EPA exerted significant bactericidal and bacteriostatic effects against both P. aeruginosa and S. aureus.