Unbalanced omega-6/omega-3 ratio in red meat products in China

Dietary meats play a crucial role in human health. The objective of this survey was to determine the fatty acid content and omega-6/omega-3 polyunsaturated fatty acids （n-6/n-3 PUFA） ratio of fresh red meat （beef and pork） from four cities （Shanghai, Nanjing, Yinchuan and Hohhot） in China. The results showed that the n-6/n-3 PUFA ratio from all the samples ranged from 6 to 23. The total n-6 PUFA concentrations ranged from 290.54 mg/100 g in beef from Nanjing to 1601.48 mg/100 g in pork from Hohhot, whereas the total concentrations of n-3 PUFA ranged from 46.34 mg/100 g in beef from Nanjing to 96.03 mg/100 g in pork from Nanjing. The results indicated that the n-6/n-3 ratio in the red meat from all four regions is unbalanced and is much higher than that （〈 5：1） rec- ommended by the WHO/FAO. The total amount of n-3 PUFA was far lower than the required daily dose. There- fore, potential solutions to increase the n-3 PUFA content in meat products or to provide alternative source of n-3 PUFA should be explored.

Red meat intake and the risk of endometrial cancer:Metaanalysis of observational studies

AIM:To evaluate whether red meat intake is related to the risk of endometrial cancer(EC) using meta-analysis.METHODS:We searched Pub Med,EMBASE,and the Cochrane Library up to June 2013,using common keywords related to red meat and EC.Case-control studies and cohort studies comparing the risk of endometrial cancer among categories by the amount of intake were included.Eleven case-control studies and five cohort studies met our criteria.We performed a conventional and a dose-response meta-analysis of case-control studies using the Der Simonian-Laird method for random-effects.For cohort studies we performed a conventional meta-analysis.Publication bias was evaluated using Egger's test.RESULTS:In the meta-analysis of 11 case-control studies including 5419 cases and 12654 controls,higher red meat consumption was associated with an increased risk of EC [summary relative risk(SRR) = 1.43,95%CI:1.15-1.79;I2 = 73.3% comparing extreme intake categories).In a dose-response analysis,for red meat intake of 100 g/d,SRR was 1.84(95%CI:1.64-2.05).In contrast,in the meta-analysis of five prospective studies including a total of 2549 cases among 247746 participants,no significant association between red meat intake and EC risk(SRR = 0.97,95%CI:0.85-1.11;I2 = 4.9% comparing extreme intake categories) was observed.CONCLUSION:Our meta-analysis found a significantlinear association between red meat intake and EC risk based on case-control studies but this was not confirmed in prospective studies.

An Assessment of Barriers to MSMEs’ Adoption of CSA in Livestock Red Meat Value Chain, Kajiado County, Kenya

Climate change poses great risks to poverty alleviation, food security and livelihoods sustainability in sub-Saharan Africa, declining crop yields and livestock productivity, especially in ASALs that suffer from fragile ecosystems characterized by frequent droughts and low rainfall. Climate-Smart Agriculture (CSA) objectives of improving productivity and incomes, adaptation, resilience to climate change and mitigation on GHGs emissions, are responses to these climate risks. CSA technologies, innovation and management practices (TIMPs) in general do exist, however they are concentrated in crop farming neglecting livestock production and especially in marginalized areas such as ASALs, which forms 85% of Kenyan land mass and is dominated by pastoral and nomadic livestock production. Most CSA practices are mainly at the production level and hardly extend to the entire value chain, and diffusion is slow due to several barriers. A mixed method approach was used to evaluate barriers to actors’ adoption of CSA in the pastoral Livestock red meat value chain starting from input suppliers, producers, to consumers (pasture to plate). This study used six broad perspectives to examine the barriers: 1) Knowledge and institutional;2) Market and financial;3) Policy and incentives;4) Networks and engagement platforms;5) Cultural and social;6) Physical infrastructure barriers. These barriers can be surmounted with concerted efforts from the government, development partners, pastoral communities, value chain actors and public private partnership among others. Efforts such as modernization of the pastoral red meat value chains, integration of MSMEs into the livestock systems, access to affordable financing, availability of context based, affordable CSA TIMPs, incentives, policies and institutional support, which currently remains inadequate. Institutional barriers like lack of capacity, coupled with knowledge and behavioral barriers hinder adoption. Financial institutions and cooperative societies can be enablers, however, their reluctance to invest in the sector is a barrier too.

Association of Red Meat Usual Intake with Serum Ferritin and the Risk of Metabolic Syndrome in Chinese Adults: A Longitudinal Study from the China Health and Nutrition Survey

Objective The present study aimed to investigate the association of red meat usual intake with metabolic syndrome(Met S),and explore the contribution of red meat usual intake to serum ferritin.Methods Based on the data from the longitudinal China Health and Nutrition Survey(CHNS),2,797 healthy adults aged 18–75 years without hypertension,diabetes,and Met S were selected in 2009 as subjects and follow-up studies were carried out till 2015.We used the National Cancer Institute(NCI)method to estimate the usual intake of foods.Multivariable logistic regressions were performed to evaluate the association between red meat usual intake and the risk of Met S.Quantile regression analysis was used to study the relationship between red meat consumption and serum ferritin levels.Results After adjusting for potential confounders,red meat,and fresh red meat were positively associated with the risk of Met S(RR=1.41,95%CI:1.05–1.90 and RR=1.37,95%CI:1.02–1.85,respectively).These relationships showed increasing trend(P<0.05).The level of serum ferritin increased significantly with the number of Met S components(P<0.05).The quantile regression analysis showed that red meat and fresh red meat usual intake had a significant positive association with serum ferritin levels across the entire conditional serum ferritin distribution(P<0.05).Processed red meat did not exhibit a similar association.Conclusion Higher red meat usual intake was associated with an increased risk of Met S and elevated serum ferritin levels.

Natural radioactivity measurements of frozen red meat samples consumed in Iraq

Purpose In the present study,the activity concentrations of long-lived gamma-ray emitters(^(238)U,^(232)Th and ^(40)K)in ten dif-ferent types of frozen red meat samples selected from markets in Iraq were measured.Methods The technique of gamma spectrometer equipped with scintillation detector NaI(Tl)was used.Results The annual effective dose was estimated in adults and kids.The results showed that the concentrations of ^(238)U,^(232)Th and ^(40)K were found in the range of permissible limits of 30,32 and 400 Bq kg−1,respectively.On the other hand,the maximum values of ^(238)U and ^(232)Th in beef samples are higher than in lamb meat samples.The annual effective dose of adults and kids was observed to be below the limit(1.0 mSv)recommended by ICRP.Conclusion The frozen red meat samples are safe for human consumption and have gamma-ray emitter concentrations lower than the maximum permissible levels.

Red Meat Is Strongly Linked to Cancer

营养学家认为,人们应减少红肉和加工肉类(如香肠、腊肉、火腿、腌肉 等)的摄入量,因为大量食用红肉容易导致肠癌,他们建议人们用白肉(鱼肉、鸡 肉、鸭肉)代替红肉(牛肉、猪肉、羊肉等)。

Consumption of red and processed meat and esophageal cancer risk:Meta-analysis

To summarize the evidence about the association between red and processed meat intake and the risk of esophageal cancer,we systematically searched the PubMed and EMBASE databases up to May 2012,with a restriction to English publications,and the references of the retrieved articles.We combined the studyspecific relative risks(RRs) and 95%CI,comparing the highest with the lowest categories of consumption by using a random-effects model.A total of 4 cohort studies and 23 case-control studies were included in the meta-analysis.The combined RRs(95%CI) of the cohort studies comparing the highest and lowest categories were 1.26(1.00-1.59) for red meat and 1.25(0.83-1.86) for processed meat.For the case-control studies,the combined RRs(95%CI) comparing the highest and lowest categories were 1.44(1.16-1.80)for red meat and 1.36(1.07-1.74) for processed meat.Findings from this meta-analysis suggest that a higher consumption of red meat was associated with a greater risk of esophageal cancer.

性别对红骨绵羊肌肉食用和营养品质的影响

为探究盐源县不同性别红骨绵羊的肉质特性,本试验以该绵羊的背最长肌为材料,测定其肉质理化指标和营养指标,研究性别对红骨绵羊肉品质特性的影响。结果表明盐源红骨绵羊肉的pH值、熟肉率、剪切力和色差等指标在公母之间均无显著性差异(P>0.05),营养指标中常规营养成分、氨基酸、重金属等指标在公母之间均无显著性差异(P>0.05),矿物质含量中钙元素在公母之间具有显著性差异(P<0.05),表明性别对红骨绵羊肉除矿物质元素钙以外的pH值、嫩度、熟肉率、常规营养成分、氨基酸及重金属含量等指标均没有显著的影响。

皮山红羊肉用性状的研究分析

试验旨在探究皮山红羊的背膘厚度、眼肌面积和眼肌深度等肉用性状指标与体重的相关性,为皮山红羊的生产和选育提供参考。试验选择饲养管理均相同的506只6月龄皮山红羊,利用便携式B超诊断仪测量背膘厚度、眼肌深度和眼肌面积等肉用性状指标和体重,采用SAS 9.2进行影响因素的分析,采用SPSS 25.0软件进行相关性分析。结果显示,产羔类型、性别和群别分别对背膘厚度、眼肌深度和眼肌面积有显著或极显著影响(P<0.05或P<0.01)。单羔的眼肌深度极显著高于三羔(P<0.01),且双羔眼肌深度显著高于三羔(P<0.01),单羔眼肌面积极显著高于多羔(P<0.01),双羔眼肌深度显著高于三羔(P<0.05),且显著高于四羔(P<0.05)。性别对于3个肉用性状指标具有极显著影响(P<0.01),其中公羔在背膘厚度、眼肌深度和眼肌面积方面均高于母羔。眼肌面积与体重的相关性最高,其次为眼肌深度和背膘厚度,眼肌面积对于皮山红羊直接作用最大,其次是眼肌深度和眼肌面积。研究表明:6月龄羔羊的背膘厚度、眼肌深度和眼肌面积三个肉用性状受到羔羊出生类型、性别及其饲养管理方式的影响,在绵羊饲养管理和选种选育时应考虑它们对6月龄羔羊上述性状的影响,提高对上述肉用性状选育及遗传评估准确性。

基于生物技术的红肉鱼副产物高值化利用研究进展

青皮红肉鱼是一类产量高却利用率低的低值海产品,将其加工副产物利用生物技术进行高值化利用成为研究重点。有研究证明海洋生物活性肽是一类极具开发潜力的新型药物来源。目前,对红肉鱼生物活性肽制备技术和生物应用方面的研究较少。综述了以青皮红肉鱼加工副产物为原料制备生物活性肽,以及体内体外的生物活性表征。介绍了红肉鱼生物活性肽的抗氧化、抗糖尿病、降血压、抗菌等功能活性,以便为开发新型海洋药物提供理论依据。

三种天然红色素在素肉肠中的应用比较研究

为探究天然红色素在素肉制品中的着色效果,比较了番茄红、红曲红、高粱红在素肉肠熟化前后,不同光照、真空度、贮藏温度及反复冻融条件下的着色稳定性,以感官评分为指标评价了3种色素在素肉肠中应用效果。结果表明,番茄红素肉肠在熟化前后,不同光照、真空度、贮藏温度及反复冻融条件下的稳定性优于红曲红及高粱红。

火龙果果皮红色素抑菌活性及对鳙鱼肉新鲜度的指示效应

本研究通过超声波辅助乙醇浸提法提取火龙果果皮红色素,采用药敏试纸抑菌圈检验法、DPPH自由基清除法比较两种果皮红色素的抑菌活性和总抗氧化能力,同时结合果皮红色素提取物对pH变化的响应和色差值评估指标,优选红色素提取物浓度制作指示卡。通过检测常温放置过程中鱼肉的pH、脂质过氧化值变化评估指示卡对鳙鱼鱼肉新鲜度的指示效果。结果表明,红肉红皮火龙果果皮红色素对大肠杆菌(Escherichia coli)和金黄色葡萄球菌(Staphylococcus aureus)的抑菌活性和总抗氧化能力均显著高于白肉红皮火龙果果皮红色素(P<0.05),且其红色素提取物水溶液对pH2~13具有较灵敏的呈色变化反应。应用10 g/L红肉火龙果果皮红色素提取物制备的指示卡,评估鳙鱼鱼肉变化可知,25℃常温放置12 h过程中鱼肉的pH先微降后上升,TBA脂质过氧化值持续升高为0 h的1.96倍,揭示鱼肉的新鲜度下降;同期,放置鱼肉的指示卡色差值ΔE也从起始时1.40(0 h)上升到18.30(12 h),指示卡外围呈色从淡红色向玫红色及土黄色转变,对放置的鲜切鳙鱼肉新鲜度的衰减表现出较为直观的指示效应。本研究为火龙果果皮天然红色素的综合利用提供前期的科学依据,也为水产类预制菜行业的新型食品包装应用提供初步参考。

The significance of N‑carbamoylglutamate in ruminant production

Improving the efficiency and production of grazing ruminants to support food and fiber production,while reducing the environmental footprint and meeting the welfare needs of the animals,is important for sustainable livestock production systems.Development of new technologies that can improve the efficiency of nitrogen(N)utilization in ruminants,and that are effective and safe,has important implications for ruminant livestock production.N-carbomoylglutamate(NCG)is a functional micronutrient that stimulates endogenous synthesis of arginine,which can improve survival,growth,lactation,reproductive performance,and feed efficiency in mammals.There is a growing body of evidence to support the potential of dietary NCG supplementation to improve the productive capacity and N utilization efficiency of ruminants.This review summarizes the current literature on the effects of dietary supplementation with NCG in ruminants and impacts on production and potential to reduce the environmental footprint of farmed ruminant livestock.The current literature highlights the potential for commercial application in ruminant livestock to improve productivity and N utilization efficiency.

红肉及肉制品摄入与炎性肠病相关性的研究进展

炎性肠病(IBD)是一种慢性复发性疾病,其病因及发病机制复杂,至今尚未明确。饮食习惯与IBD的相关性是近年研究的热点,红肉及肉制品摄入过多与IBD的患病风险增加显著相关。该饮食习惯可通过改变肠道菌群、破坏肠道黏膜完整性、减少肠道内有益短链脂肪酸的含量、产生有害气体促进肠道内各种免疫反应产生,进而导致肠道炎症。因此,深入研究红肉及肉制品摄入与IBD的关系及其发病机制,并优化饮食结构,可为预防和治疗IBD提供新策略。

平凉红牛生长性能、胴体及肉质性状分析

【目的】通过研究平凉红牛的生长性能、胴体性状和肉质性状,深入挖掘平凉红牛的肉用特征和遗传特性,为平凉红牛新品种选育提供参考。【方法】试验选取24头平凉红牛阉牛,经强度育肥180 d后屠宰,年龄在24-36月龄,对其体尺、屠宰性能、胴体指数进行测定,并选取其中3头的外脊和大黄瓜条进行肉质测定分析。【结果】经育肥后的成年平凉红牛体重、体高、十字部高、胸围、管围相较于2019年测定的22-28月龄的平凉红牛分别增长6.96%、4.61%、4.43%、4.28%、7.90%,体斜长减少3.52%;胴体重为(417.01±56.94)kg、净肉重为(372.48±54.60)kg、屠宰率为61.56%±1.86%、净肉率为54.92%±2.60%,相较于2010年测定的24月龄平凉红牛数据分别增长12.61%、19.16%、-1.91%、3.82%,肉骨比为8.65±2.00,相较于2012年测定的22-27月龄数据增长27.96%;此外高档肉块重(里脊、外脊、眼肉、上脑)为(51.59±7.92)kg,优质肉块重(臀肉、霖肉、米龙、大黄瓜条、小黄瓜条、辣椒条、肩肉)为(62.62±5.56)kg,分别占净肉重的13.91%±1.45%和17.07%±2.24%,平凉红牛的生长性能和产肉性能良好。在肉品质方面,外脊和大黄瓜条的剪切力分别为2.72 kg和4.43 kg,比市场购买的A3级雪花牛肉分别低19.58%和64.82%,但差异不显著(P>0.05);外脊和大黄瓜条的粗蛋白含量均达到了20%以上,且平凉红牛外脊的粗蛋白含量显著高于雪花牛肉(P<0.05)。外脊和大黄瓜条的EAA/NEAA比值分别为71%和68%,较高于FAO/WHO的标准值(60%);EAA/TAA比值分别为42%和41%,略高于FAO/WHO的标准值(40%)。相较于市场购买的A3级雪花牛肉,平凉红牛外脊和大黄瓜条的必需氨基酸和呈味氨基酸含量高;对外脊和大黄瓜条肉块进行氨基酸评分分析,平凉红牛外脊和大黄瓜条的赖氨酸均高于FAO/WHO氨基酸评分标准模式;此外,大黄瓜条中硒含量极显著较高(P<0.01),铁、锌、PUFA含量、n-6/n-3和PUFA/SFA比值均显著较低(P<0.05);外脊中EPA含量显著较高(P<0.05)。【结论】经过改良和选育,平凉红牛的体格增大、胸围增长,体躯紧凑,肉用性能提高;平凉红牛肉质具有细嫩鲜美、风味浓厚、营养价值高的特点,极具开发利用价值。

基于顶空-气相色谱-离子迁移谱分析蒸制过程中草鱼肉挥发性成分的变化

为提高蒸制草鱼的风味品质,通过顶空-气相色谱-离子迁移谱(headspace-gas chromatography-ion mobility spectroscopy,HS-GC-IMS)结合主成分分析(principal component analysis,PCA)及感官评定研究了草鱼白肉和红肉在蒸制过程中挥发性成分的变化。在鱼肉中共鉴定出40种化合物,其中白肉(34种)和红肉(37种)共有的挥发性化合物有30种,主要是醛类、醇类、酮类和酯类。蒸制处理会促进鱼肉中挥发性化合物(异丁醛、戊醛、己醛、庚醛、2-乙基己醇和2-戊酮)的形成;蒸制后,红肉中挥发性成分的数量和相对含量都高于白肉。PCA结果表明,在蒸制过程中,红肉的风味变化较白肉更为丰富。在蒸制时间到达9 min时,鱼肉整体的风味趋于稳定,鱼肉中的挥发性成分可以代表熟草鱼肉的风味。感官评定的结果也显示,蒸制9 min的草鱼肉具有较好的风味和整体可接受度。综上,HS-GC-IMS和PCA的组合可以较好地描述不同蒸制时间的草鱼白肉和红肉挥发性化合物的变化,并为确定草鱼适宜的蒸制时间提供依据。

平凉红牛CD36基因外显子8(exon 8)多态性及其与肉质性状相关性分析

试验旨在研究平凉红牛CD36基因外显子8(exon 8)多态性及其与肉质性状的关联性。试验利用PCR-SSCP技术、DNA测序技术、实时荧光定量PCR(qPCR)技术进行SNPs位点基因型分型和mRNA表达量测定,分析其与肉质性状的相关性。结果显示,平凉红牛CD36基因exon 8检测出1个SNP位点(g.79219 C>A,aa.Lys>Thr),基因型分为CD和CC型,CD基因型宰前活重、肌内脂肪含量、眼肌面积、胴体重明显高于CC基因型(P<0.05);CD36基因在不同组织器官均表达m RNA,腿肌、背最长肌mRNA表达量较高。研究表明,CD36基因对平凉红牛肉用性状影响较大,可作为改善肉品质的候选分子标记基因。

北京地区孕早期孕妇膳食蛋白质摄入与妊娠期糖尿病的关系

目的了解北京地区孕早期孕妇膳食蛋白质摄入情况,探讨膳食蛋白质摄入频率与妊娠期糖尿病(gestational diabetes mellitus,GDM)的关系。方法本研究数据来自北京出生队列研究(Beijing Birth Cohort Study),最终纳入10320例于2018年9月至2020年12月在首都医科大学附属北京妇产医院门诊进行常规产检的孕6~16周健康单胎孕妇,通过食物频率法了解孕早期孕妇膳食蛋白质摄入情况。于孕24~28周行75 g口服葡萄糖耐量试验,根据国际糖尿病与妊娠研究组(International Association of the Diabetes and Pregnancy Study Groups,IADPSG)标准诊断GDM。采用χ^(2)检验分析研究对象基线特征与GDM发病率的关系,采用多因素Logistic回归分析方法探讨膳食蛋白质摄入频率与GDM发病率的关系。结果①本研究纳入的10320例孕妇中确诊为GDM的有1585例,发病率为15.4%。②单因素分析结果显示,总蛋白质类食物、动物蛋白、红肉的摄入频率与GDM的发生风险有关(P<0.05),每周摄入频率越高,GDM发病率越高;而植物蛋白、白肉摄入频率与GDM的发生风险无关(P>0.05)。进一步分析显示,猪肉的摄入频率与GDM的发生风险有关(P<0.05),摄入频率越高,GDM发病率越高。③多因素Logistic回归分析结果显示,在控制了年龄、学历、产次、孕前体质量指数(body mass index,BMI)、糖尿病家族史后,孕早期蛋白质类食物总摄入频率增加会增加GDM的发生风险(OR=1.504,95%CI:1.138~1.988);其中动物蛋白摄入频率对GDM发生有影响(OR=1.429,95%CI:1.122~1.984),而未发现植物蛋白摄入频率对GDM发生有影响。进一步分析显示,红肉的摄入频率增加会增加GDM的发生风险(OR=1.288,95%CI:1.072~1.547),而未发现白肉摄入频率对GDM发生有影响。在红肉类别中,猪肉的摄入频率增加会增加GDM的发生风险(OR=1.025,95%CI:1.007~1.044)。结论北京地区孕早期孕妇膳食蛋白质的主要来源为动物蛋白中的肉类。较高的动物蛋白摄入频率,特别是以猪肉为主的红肉,是GDM发生的危险因素,而白肉和植物蛋白摄入频率与GDM发生无关。妇幼保健人员应该开展孕早期,甚至备孕期的营养宣教,以利于GDM的预防。

饲粮中添加牛至精油后平凉红牛肌肉品质、脂肪酸及氨基酸的组成和含量

选取健康状况良好、初始体重相近的9头平凉红牛阉牛,分为3组,每组3头。对照组(CON组)饲喂基础饲粮,试验组则在基础饲粮基础上每头每天添加10 g(L组)、20 g(H组)牛至精油,预试期14 d,正试期570 d,取左半胴体半腱肌测定肉品质、脂肪酸和氨基酸含量,研究长期添加牛至精油后平凉红牛肌肉品质、脂肪酸及氨基酸的组成和含量变化。结果表明:1)排酸时间相同牛至精油添加量不同时,排酸0 h,L组失水率显著低于CON组(P <0.05),H组熟肉率显著高于CON组(P <0.05),L组剪切力显著低于CON组(P <0.05)。排酸72 h后,H组肌肉亮度值显著高于CON组(P <0.05),试验组滴水损失显著低于CON组(P <0.05),L组蒸煮损失显著低于CON组(P <0.05)。牛至精油添加量相同排酸时间不同时,CON组中,72 h肌肉亮度、红度值、黄度值、失水率和蒸煮损失显著高于0 h(P <0.05),0 h pH和熟肉率显著高于72 h(P <0.05)。L组中,72 h肌肉亮度值、黄度值和失水率显著高于0 h(P <0.05),0 h pH显著高于72 h(P <0.05)。H组中,72 h肌肉亮度值、红度值、失水率和蒸煮损失显著高于0 h(P <0.05),0 h pH和熟肉率显著高于72 h(P <0.05)。2)试验组硬脂酸(C18:0)、油酸(C18:1n9c)和不饱和脂肪酸(USFA)含量显著高于CON组(P <0.05),L组山嵛酸(C22:0)显著高于CON和H组(P <0.05)。3)试验组苏氨酸、缬氨酸、蛋氨酸、异亮氨酸、亮氨酸、苯基丙氨酸、赖氨酸、丙氨酸、天冬氨酸、丝氨酸、脯氨酸、酪氨酸、精氨酸、必需氨基酸、非必需氨基酸和氨基酸总量显著高于CON组(P <0.05),L组谷氨酸含量显著高于CON组(P <0.05)。综上所述,长期饲喂牛至精油可以改善育肥后期平凉红牛的肌肉品质并提升肌肉中脂肪酸和氨基酸含量。