Analysis of preference for domestic grass‐fed beef in Japanese youths

A questionnaire based on sensory evaluation of completely domestic grass‐fed beef was carried out on 157 Japanese undergraduate students aged between 18 and 22 years in Kitasato University. The sensory evaluation sheet consisted of 10 questions concerning preference for domestic grass‐fed beef, and three demographic/lifestyle questions. Using principal component analysis and cluster analysis, the respondents were divided into four groups (G1–G4). G1 accepted almost all properties. G2 accepted most properties but disliked chewiness. G3 accepted juiciness and flavor but disliked the color and texture of the meat. G4 tended to dislike almost all properties. According to chi‐square test, most G2‐people statistically liked other commercial beef and G4‐people had neutral and negative impressions. G1‐ or G3‐people did not have any significant tendency as regards beef preference. These results indicate that most of the young respondents who preferred domestic grass‐fed beef could not accept its texture, and some respondents could accept its juiciness and flavor. It is also suggested that a part of the people who like commercial beef do not prefer chewiness of grass‐fed beef. Such information will aid grass‐fed beef cattle breeders, producers and packers to improve the quality of beef and its evaluation.     

苜蓿多叶品系BC2群体农艺性状改良效果研究

为研究苜蓿(Medicago sativ a L.)多叶品种回交后代的农艺性状改良效果,本研究以'淮阴苜蓿'为轮回亲本,多叶苜蓿'PL34HQ'为非轮回亲本,获得BC2(回交二代)材料,对其株高、多叶率、分枝数等数据进行相关、聚类和主成分分析.结果显示:BC2群体材料在综合性状上偏向于轮回亲本'淮阴苜蓿',但仍有不少植...     

Microarray analysis of Longissimus thoracis muscle gene expressions in vitamin A‐restricted Japanese Black steers in middle fattening stage

Vitamin A (VA) restriction in beef cattle improves meat marbling; however, the underlying molecular mechanisms remain incompletely understood. We performed microarray analysis to clarify the effect of VA restriction on Longissimus thoracis gene expressions in Japanese Black steers. Six Japanese Black steers 13–14 months of age were divided into two groups: S group (n = 3), which received VA supplementation, and R group (n = 3), in which dietary VA intake was restricted. Steers were fattened for 7 months, following which tissue samples were obtained. Extracted RNA samples were analyzed by Affymetrix Genechip Bovine Genome Array. Lists of genes highly expressed in the R and S groups were obtained. The lists were functionally interpreted using functional annotation software, DAVID. In the R and S groups, 48 and 40 genes were significantly highly expressed, respectively. The gene list of the R group included CD36, LPL, GPAM, DGAT2, and SCD and additional genes annotated ‘PPAR signaling pathway,’ ‘lipid biosynthesis’ and ‘mitochondrion,’ whereas that of the S group included COL1A2, FN1 and DCN and additional genes annotated ‘extracellular matrix.’ Changes in the expression of these genes are possibly involved in marbling improvement in beef cattle by VA restriction.     

Search for an index for the taste of Japanese Black cattle beef by panel testing and chemical composition analysis

To search for an index for chemical composition related to superior taste in Japanese Black beef, we conducted panel tests and analyzed the chemical composition of seven beef brands. Thirty‐five sirloin beefs from five heifers were used in this study, sold under seven beef brands graded as more than A4 on the Japanese Meat Grade scale. The chemical composition analyses assessed both raw and roasted meat, the latter of which was roasted under the same conditions as those used for the panel test. Results of the panel test and chemical composition analyses revealed that fatty acid composition, sugar content, adenosine triphosphage (ATP)‐related compounds, amino acid composition and odor composition in the sirloin meat differed among beef brands. Furthermore, the correlations of chemical compositions between roasted and raw meat were significantly high. Sugar content and ATP‐related compounds in roasted meat were significantly correlated with the item ‘overall evaluation’ of the panel test. ATP‐related compounds, such as inosinic acid, carnosine and taurine, in roasted and raw meat were correlated significantly with the item ‘umami intensity’ of the panel test. These results suggest that the composition of these components is important for an index related to the overall evaluation of beef.     

Comparison of feeding systems: feed cost,palatability and environmental impact among hay‐fattened beef,consistent grass‐only‐fed beef and conventional marbled beef in Wagyu (Japanese Black cattle)

The objective of this article is to compare feed cost, palatability and environmental impacts among feeding systems of high concentrate (HC), high hay (HH) and grass‐only‐fed (Gof) groups. Feed cost was the sum of costs paid for feed intake times the price of feed per kilogram. Palatability was measured by a panel taste test using HH and Gof beef and analyzed for differences. Environmental impacts were calculated based on 1 kg of Japanese beef yield of CO₂ equivalents (eq) and animal end weights at each feeding stage. Results showed that the HH and Gof feeding systems could significantly reduce feed costs by approximately 60% and 78%, respectively, from the HC. In the panel taste test, 50% and 47.50% of panelists indicated that HH beef was ‘extremely delicious’ and ‘acceptable,’ respectively, while 15% indicated that Gof beef was ‘extremely delicious’; 62.50% indicated that Gof beef was ‘acceptable.’ Environmental impacts of each feeding system in terms of CO₂ equivalents (eq) were 9.32, 6.10 and 2.04 tonnes of eq for the HC, HH and Gof, respectively. The HH was an economical system that produced moderate impacts on the environment and had impressive taste.     

Application of highly differentiated SNPs between Japanese Black and Holstein to a breed assignment test between Japanese Black and F1 (Japanese Black x Holstein) and Holstein

Two taurine breeds, Japanese Black and Holstein, established from geographically distant origins and selected for different uses, beef and dairy, were extensively genotyped using a genome‐wide single nucleotide polymorphism (SNP) chip with more than 1000 animals of each breed. The genetic structure was examined by principal component analysis, in which the first principal component clearly separated the two breeds and explained more than 15% of the variance. Highly differentiated SNPs were detected throughout the genome, some of which were clustered within small regions on BTA4 (79.2–79.7 Mb, Btau4.0) and BTA26 (22.2–23.6 Mb). A breed assignment test was developed using 18 highly differentiated SNPs to distinguish Japanese Black from F₁ (Japanese Black × Holstein) and Holstein. The error rate that an F₁ or Holstein animal is misjudged as Japanese Black was expected to be < 0.8%, while the error rate that a Japanese Black animal is misjudged as F₁ or Holstein was expected to be < 0.001%. This test provides a reliable and powerful method to detect breed label falsification in retail beef.     

基于SSR分子标记的13个白三叶(Trifolium repens L.)品种指纹图谱构建

白三叶(Trifolium repens L.)是一种多年生冷季型豆科牧草,因其具有产量高、品质优良等特点,已成为我国西南地区重要的优质牧草.为分析国外引进的白三叶新品种的遗传多样性,本研究利用简单重复序列(Simple sequence repeats,SSR)分子标记对13个白三叶品种进行品种鉴定及DNA指纹图谱的...     

LAL试验快速检测肉品细菌污染程度及鲜度的研究

对不同鲜度的猪肉、牛肉、羊肉、鸡肉和鱼肉进行活菌总数、革兰氏阴性菌数、大肠菌群数及挥发性直基氮（TVB－N）测定，并与LAL试验（鲎变形细胞溶解物试验）进行平行对比研究，证实肉品的鲜度与其细菌总数、革兰氏阴性菌数及LAL指数呈负相关性。应用LAL试验可在短时间（1－2小时）内快速判定肉品的细菌污染程度及鲜度，比传统的细菌培养计数法大大缩短了时间，适合现场大批量肉品细菌污染程度及鲜度的快速检测。     

47份箭筈豌豆品种(系)在青海作秋绿肥的能力评价北大核心CSCD

箭筈豌豆是我国重要的肥饲兼用绿肥作物之一,麦田套复种箭筈豌豆是青海等西北地区重要的农牧结合措施。在青海农区,田间条件下分析了47份箭筈豌豆品种(系)分枝期和初花期地上部生物量、氮磷钾累积量及土壤速效养分含量变化。运用主成分分析和聚类分析对不同箭筈豌豆品种氮磷钾吸收能力进行综合评价,以期筛选出适宜青海地区作绿肥栽培的品种(系)。结果表明,47份箭筈豌豆资源初花期鲜草产量及氮磷钾累积量分别为21.33~47.31 t·hm^(-2)、100.34~212.51 kg·hm^(-2)、10.31~25.25 kg·hm^(-2)和63.89~140.41 kg·hm^(-2)。匈牙利初花期鲜草产量、氮钾累积量均最高,比当地主栽品种西牧333分别提高了58.92%、44.78%和54.40%。7501磷累积量最高,比西牧333提高了27.78%。两个时期生物量及氮磷钾累积量10个指标的主成分分析显示排名前五的品种分别为匈牙利、草原79-1、清水河麻箭豌(麻色)、324和黑皮741箭豌,匈牙利综合得分最高(6.84),751箭豌得分最低(-3.87)。聚类分析显示,氮磷钾素吸收能力均聚为强、中、弱3类。氮素方面,吸收能力强的有4份资源,占8.51%,包括初花期氮累积量最高的匈牙利;吸收能力居中的有33份资源,占70.21%;吸收能力弱的有10份资源,占21.28%。磷素方面,吸收能力强的有7份资源,占14.89%,包括初花期磷素累积量最高的7501;吸收能力居中的有28份资源,占59.58%;吸收能力弱的有12份资源,占25.53%。钾素方面,吸收能力强的有8份资源,占17.02%,包括初花期钾累积量最高的匈牙利;吸收能力居中的有37份资源,占78.72%;吸收能力弱的有2份资源,占4.26%。47份箭筈豌豆资源的氮磷钾吸收能力表现出明显的差异,氮磷钾吸收强的分别有4、7和8份,这些资源平均吸氮量、吸磷量和吸钾量分别达到200.62 kg·hm^(-2)、23.10 kg·hm^(-2)和115.23 kg·hm^(-2)。种植箭筈豌豆可显著降低分枝期和初花期土壤无机氮、有效磷和速效钾含量,能够充分利用休闲期土壤养分。综合来看,主成分分析显示排名前五的品种中匈牙利、草原79-1、清水河麻箭豌(麻色)和324表现较强的氮、钾吸收能力,草原79-1和匈牙利表现出较强的磷、钾吸收能力,可作为青海省有潜力的箭筈豌豆品种(系)在生产中验证。     

宁夏引黄灌区2个苜蓿品种不同行比混播模式研究

试验采用单因素随机区组设计,探讨了宁夏引黄灌区滴灌条件下苜蓿(Medicago sativa)品种'三得利'与'巨能7'单播及以1:1,1:2,1:3行比混播对草地生产性能、品质的影响,并利用主成分分析方法(Principal compo-nent analysis,PCA)进行综合评价,以期得到该区域2个苜蓿品种混播...     

LAL试验快速检测牛羊肉细菌污染程度的研究

对２１份牛羊肉进行微生物及鲜度指标测定衣与ＬＡＬ试验（鲎变形细胞溶解物试验）结果进行平行对比研究。发现ＬＡＬ试验结果与微生物及鲜度指标测定结果呈正相关,根据ＬＡＬ指数,可快速判定肉品的细菌污染程度及鲜度。     

Japanese consumer categorisation of beef into quality grades,based on Meat Standards Australia methodology

The objective was to evaluate the sensory categorisation of beef by Japanese consumers, based on Meat Standards Australia methodology. Various cuts of beef, with a wide range of quality (from Australian and Japanese cattle) and three cooking methods (grill, yakiniku, shabu shabu), were evaluated by 1620 Japanese consumers in Tokyo and Osaka. Consumers rated each sample for four sensory attributes (tenderness, juiciness, flavor and overall satisfaction), then selected one of four grades (unsatisfactory/2‐star, good everyday/3‐star, better than everyday/4‐star, and premium quality/5‐star), based on the quality of the beef within each cooking method. Meat quality scores, denoted as MQ4 scores (weighted combination of the four sensory attributes) were calculated from the Japanese consumer test results, to describe the Japanese consumer rating of beef. The distribution of the Japanese consumer MQ4 scores showed a clear distinction between grades, with the majority of scores being included within the boundaries of each grade. The MQ4 score allocated approximately 64% of the samples to their correct consumer grades. The MQ4 score showed potential to be used as a tool in developing and monitoring a consumer‐focused grading system that is able to predict Japanese consumer satisfaction of individual beef cuts prepared by different cooking methods.     

基于主成分分析综合评价23份白沙枇杷果实营养品质

为了科学的评价不同白沙枇杷品种果实品质指标,建立高效白沙枇杷果实品质评价体系,本研究通过相关性分析法和主成分分析法对23份白沙枇杷果实的11个品质指标进行了系统分析。结果表明,不同品种的果实各个品质指标之间存在较大差异,且具有不同程度的相关性。采用主成分分析法从11个品质指标中提取出4个主成分因子。综合相关性分析和主成分分析,可溶性糖、可滴定酸、氨基酸(AA)和单果重作为白沙枇杷果实品质性状评价的核心指标。采用相关性分析和主成分分析综合评价方法为评价品质优良的白沙枇杷品种提供参考依据。     

2019年北京、上海和广州消费者猪肉消费习惯以及偏好的调查分析

文章通过问卷访问调查的方法，分析北京、上海以及广州消费者猪肉消费习惯以及对猪肉品质特征的考量。笔者分析发现，在生鲜猪肉的购买地点上，北上广消费者有着不同的消费习惯。北京消费者主要在超市购买猪肉，而广州消费者主要在农贸市场购买猪肉。在猪肉品质的考量上，北上广消费者均对猪肉卫生安全最为敏感，其次是猪肉的新鲜程度，最后是价格和口感。但各个城市对猪肉品质特征的偏好也有明显的差异。笔者发现，北京消费者更加偏好食品卫生安全，上海的消费者比较重视猪肉的口感，而广州消费者比较重视新鲜程度。此外北上广消费者在肉类食品消费结构上有显著的差异。北京消费者的猪肉和羊肉消费量相对较高，上海消费者牛肉消费量相对较高，而广州消费者鸡肉消费量相对较高。     

不同紫花苜蓿种质材料萌发期耐盐性鉴定与综合评价

通过对59份紫花苜蓿种质材料耐盐性鉴定和指标筛选,从而为紫花苜蓿耐盐育种、耐盐机制以及耐盐基因克隆等研究提供基础材料。本试验采用220 mmol·L^-1的NaCl溶液对不同来源的紫花苜蓿种质材料进行盐胁迫,测定紫花苜蓿萌发期8个相关指标,用主成分分析、逐步回归分析和聚类分析等方法对其耐盐性进行综合评价和耐盐指标筛选。结果表明：各指标对照组与处理组间的差异达到极显著水平（P<0.01）;根长、根芽比、发芽指数和活力指数的耐盐系数全部分布在0～0.4范围内且分布频率均为100%,对盐胁迫的敏感程度较高;活力指数、发芽指数和萌芽指数在主成分分析中具有较高载荷;发芽率、萌芽指数、发芽指数、活力指数、发芽势与耐盐性度量值（D值）和加权耐盐系数（Weight salt resistance coefficient,WSC）关联度均较大;根据D值、综合耐盐系数（B值）和WSC值得出的逐步回归方程决定系数R²均大于0.99;综合评价中依据B值、WSC值耐盐性程度排前10的种质编号为：38,46,20,54,43,56,48,41,19,32,依据D值耐盐性程度排前10的种质编号为：38,46,54,43,20,19,56,32,41,48。聚类分析将59份种质材料划分为5类,根据类群中D值大小可认为38号材料具有极强的耐盐能力,27,29,47号材料耐盐能力极弱。综上可知,发芽指数和活力指数可作为紫花苜蓿种质资源萌发期耐盐性评价指标;紫花苜蓿萌发期耐盐性强的种质材料有‘爱开夏’、‘WL903’、‘WL404HQ’、‘东德’、‘康赛’,盐性弱的种质材料有‘敖汉’、‘金皇后’、‘挑战者’。     

不同梨品种品质分析

选取梨不同品种果实为研究对象,分析不同梨品种品质指标差异,筛选出影响梨品质的关键指标,并根据品质指标对60个梨品种进行分类。结果表明：通过相关性分析得出不同梨品种果实各项品质指标存在差异,前4个因子特征值均大于0.9,累积贡献率达78.35%。第1主成分味道因子,其大小主要由SSC、TA、pH、乙醇和乙醛决定;第2主成分甜酸度因子,其大小主要由SSC/TA决定;第3主成分粗糙度因子,其大小主要由石细胞含量决定;第4主成分重量因子,其大小主要由单果重决定;10个品质指标中有7个指标对前4个因子贡献率最大,包含了大部分信息,因此筛选SSC、TA、SSC/TA、pH、石细胞、乙醇和乙醛作为梨品质的关键指标。聚类分析将60个梨品种分成三大类。综合分析得出不同梨品种品质存在一定的差异,但各品质指标存在一定的相关性,并且同一品系的梨品种不一定具备相同的品质特点。     

不同贮藏温度市售热鲜牛肉新鲜度变化研究

为了探究不同贮藏温度对市售热鲜牛肉新鲜度的影响，试验以市售热鲜牛肉为研究对象（采自4头锦江黄牛背最长肌），测定其在不同贮藏温度（5、15、25和35℃）和相对湿度（relative humidity，RH）为80%条件下，pH、L^*、a^*、b^*值、菌落总数、硫代巴比妥酸（thiobarbituric acid reactive substances，TBARS）和挥发性盐基氮（total volatile basic nitrogen，TVB-N）含量随贮藏时间（0、6、12、24、48、72、96和120 h）的变化情况。结果表明，随着贮藏时间延长，不同贮藏温度处理组热鲜牛肉的pH均呈先降低后上升的趋势，L^*、a^*和b^*值呈先上升后降低趋势，菌落总数、TBARS和TVB-N含量呈上升趋势；且贮藏温度越高，各指标随时间变化的趋势加剧。综合分析各指标的变化规律，为了保证热鲜牛肉的新鲜度和食用安全性，在5、15、25和35℃下贮藏的热鲜牛肉，其货架期分别不能超过96、72、24和12 h。     

基于主成分分析的燕麦品种生产性能的比较研究

为进一步改造利用好萨迦县高海拔区域的中低产田,本研究以6个燕麦(Avena sativa)品种为材料,用主成分分析法对其18个农艺性状指标进行综合评价,以期筛选出生产性能较好的燕麦品种,为该地发展营养体农业提供参考.结果表明:6个品种中除'青海444'能进入蜡熟期外,其余品种均处于乳熟期,且仅'青海444'和'青引1号...