当雄牦牛肉的营养和风味特性

以市售西门塔尔牛肉（下文简称“市售牛肉”）作为对照组,研究当雄牦牛肉的营养和风味特性。采用高效液相色谱、气相色谱-质谱联用、凯氏定氮等方法分别分析当雄牦牛肉和市售牛肉中蛋白质、氨基酸、脂肪酸、挥发性风味物质、矿物质和维生素差异。结果表明：当雄牦牛肉中蛋白质含量（22.89 g/100 g）显著高于市售牛肉（P＜0.05）,剪切力及蒸煮损失率显著低于市售牛肉（P＜0.05）;当雄牦牛肉中VB1、VE含量显著高于市售牛肉（P＜0.05）,2 种牛肉中的VB2、VA含量无显著差异;当雄牦牛肉中总氨基酸、必需氨基酸、总脂肪酸及不饱和脂肪酸含量均显著高于市售牛肉（P＜0.05）;微量元素分析结果发现,当雄牦牛肉中锰、硒、镁、铁、钙元素的含量均显著高于市售牛肉（P＜0.05）;当雄牦牛肉及市售牛肉中分别检测出58、43 种挥发性风味物质,牦牛肉中醇类和酯类的种类及含量均高于市售牛肉,而市售牛肉中酚类、醛类、酮类及含氮化合物的含量均较高。因此,当雄牦牛肉具有较好的食用营养品质。     

大豆红曲对红腐乳风味及感官品质的影响

该研究以市售红腐乳为对照，采用大豆红曲（RFS）替代红曲米制备红腐乳，采用分光光度法、高效液相色谱法及气相色谱-质谱联用法分别测定红腐乳的色价、莫纳可林K含量及挥发性风味物质，并对红腐乳进行感官评价，考察大豆红曲对红腐乳品质的影响。结果表明，大豆红曲红腐乳的色价（3.76 U/g）与市售红腐乳无显著差异（P<0.05），莫纳可林K含量为0.43 mg/g。红腐乳中共检测出26种挥发性风味物质，大豆红曲红腐乳与市售红腐乳的共有挥发性风味物质主要为己酸乙酯、庚酸乙酯和十四酸乙酯。与市售红腐乳相比，大豆红曲红腐乳中风味物质类别（7种）较多，其特有风味物质为甲氧基苯肟与戊基苯，其中甲氧基苯肟来自大豆红曲。以大豆红曲为辅料所得红腐乳可满足红腐乳感官要求，感官评分为40.57分。     

两广地区8种大米酿制市售低度白酒的风味物质比对

目的 明确两广地区市售大米酿制低度白酒的风味差异。方法 采用气相色谱法、液相色谱法、气相色谱-质谱法和电子鼻, 分别对8种低度白酒(5种米香、2种豉香型白酒和1种韩国烧酒)进行香气物质、乳酸和整体风味定量比对。结果 韩国烧酒的主要风味物质及含量明显低于国产酒(P<0.05); 国产低度白酒间的主要风味物质分布差异也较大, 如醇(不含β-苯乙醇)酯比0.4~2.5、酯酸比0.20~0.51、乳酸乙酯:乙酸乙酯1.0~3.1、乳酸:乙酸0.66~2.01、β-苯乙醇23.6~51.4 mg/L; 在8个样品中共检出96种化合物, 再次确认了韩国烧酒风味组成简单与国产酒之间存在明显风味差异; 从国产酒鉴定出共有的6种醛、5种醇、1种酮、22种酯; 在2个豉香型样品中除鉴定出已知的特征烯醛、二元酸二乙酯外, 还检出苯甲酸异丁酯、反-2-辛烯酸乙酯、甲酸庚酯3种特有成分; 电子鼻分析显示硫化合物、烷类、氮氧化合物应是区分白酒的主要特征风味物质。结论 本研究证实了国产大米酿制的低度白酒间的风味存在较大差异, 为将来利用风味分析定向优化市售低度白酒提供了前期数据支持。     

哈萨克羊肉和市售普通羊肉营养品质与风味特性的对比分析研究

为了研究哈萨克羊肉质与市售普通羊肉的区别,采用凯氏定氮、液相色谱、气相色谱-质谱连用等方法分别测定蛋白质、氨基酸、脂肪、矿物质、维生素、挥发性风味物质等营养品质与风味特性的指标。结果表明:哈萨克羊肉的蛋白质、必需氨基酸含量分别为20.81%、86.69 mg/g,显著高于市售样品(P0.05);哈萨克羊瘦肉中单不饱和脂肪酸中的油酸和多不饱和脂肪酸中的亚油酸、亚麻酸、花生四烯酸含量显著高于市售样品(P0.05);与市售样品相比,哈萨克羊肉中Fe、Cu和VE的含量较高,两者的VA含量并无显著差异(P0.05);哈萨克羊肉中挥发性风味物质的种类明显多于市售样品,且酮类物质、酯类物质和含硫类物质含量较高,反,反-2,4-癸二烯醛、3,6-二甲基-2-辛酮、茨酮仅在哈萨克羊肉中检出。     

市售盐水鸭挥发性风味物质研究分析

为探明南京盐水鸭挥发性风味物质,以不同品牌和不同产品执行标准的6种市售盐水鸭为研究对象,采用固相微萃取-气相色谱-质谱联用技术(SPME-GC-MS)、电子鼻和全自动氨基酸分析仪三种技术,对不同品牌盐水鸭的气味和滋味从微观及宏观角度进行分析。SPME-GC-MS结果表明:从6种盐水鸭中共鉴定出65种挥发性化合物,其中醛类16种、烃类19种、酯类4种、酮类5种、醇类6种、酸类4种与其它11种。6种样品共有化合物为10种(醛类7种、烃类2种与醇类1种)。采用"OAV值"法确定盐水鸭关键风味化合物主要为醛类。由于各样品间挥发性化合物成分不完全相同,导致各品牌盐水鸭整体香气存在差异,该试验结果与电子鼻分析结果一致。氨基酸分析结果显示,盐水鸭样品氨基酸总含量在700~1400 ng/20μL之间,氨基酸种类和含量无明显差异(p0.05),市售盐水鸭在滋味上差异不大。     

基于气相-离子迁移谱技术分析烤羊肉串的挥发性风味成分

为构建市售烤羊肉串特征风味指纹图谱,采用气相-离子迁移谱（gas chromatography-ion mobility spectroscopy,GC-IMS）对5家烧烤店的市售烤羊肉串风味物质进行测定与分析。结果表明:共检测鉴定出82种挥发性风味化合物,包括单体和二聚体,其中烤羊肉串样品共有的物质有:醛（戊醛、壬醛、辛醛、己醛、庚醛、异戊醛、苯甲醛、3-甲硫基丙醛）,酮（2-庚酮、2-丁酮、甲基庚烯酮、3-羟基-2-丁酮、γ-丁内酯）,醇（戊醇）和酯（乙酸乙酯）。通过构建加香辛料烤制和未加香辛料烤制的羊肉串风味指纹图谱,可明显观察不同市售烤羊肉串样品异同,羊肉串在加入香辛料烤制后甲基庚烯酮的含量降低;2-庚酮、丙酮和戊醇的含量升高;己醛、壬醛、庚醛、异戊醛、苯甲醛、3-羟基-2-丁酮的含量几乎不变,可能为羊肉串烤制后本身的特征风味物质。依据指纹图谱信息对烤羊肉串样本进行主成分分析（Principal Component Analysis,PCA）,结果显示,不同市售烤羊肉串样本特征风味具有一定的差异。综上,气相-离子迁移谱可检测烤羊肉串挥发性化合物风味成分和进行多变量分析,为烤羊肉串风味评价提供一定的理论和实际应用价值。     

3种干腌火腿中细菌群落结构和风味的差异及相关性分析

为比较不同产地干腌火腿微生物多样性对风味的影响,对3种火腿（金华、宣威和如皋火腿）中的游离氨基酸、挥发性风味物质及微生物群落结构进行比较分析。结果表明,金华火腿中鲜味和甜味氨基酸含量显著高于宣威火腿（P＜0.05）,风味物质中壬醛和苯甲醛的含量高于宣威火腿,己醛含量低于宣威火腿;金华火腿中优势微生物为葡萄球菌属和四联球菌属,如皋火腿中科贝特氏菌属和宣威火腿中盐单胞菌属相对丰度高于金华火腿。葡萄球菌属与谷氨酸、蛋氨酸等游离氨基酸的产生呈显著正相关（P＜0.05）、且葡萄球菌属和四联球菌属有利于壬醛和苯甲醛等风味物质的产生,盐单胞菌属与己醛含量的变化呈正相关。该研究阐明了3种火腿中微生物菌群结构差异以及与风味相关的主要微生物,为后续筛选功能微生物与提升火腿品质提供理论基础。     

冻融对冷冻新疆馕坯及其品质的影响

为探究储运过程中冻融频次对冷冻新疆馕坯品质的影响，模拟设计冻融频次试验（0～4次），利用低场核磁共振仪、流变仪、扫描电子显微镜与傅里叶变换红外光谱仪等检测、分析冷冻新疆馕坯的水分结合状态、流变学特性、微观结构及蛋白质二级结构等的变化，并通过烘焙试验综合评价冷冻新疆馕坯的感官品质，考察其烘焙特性。结果表明：随着冻融频次增加，冷冻新疆馕坯拉伸强度与拉伸距离明显降低；其流变学特性（弹性模量G''与黏性模量G''）呈明显下降趋势；其强结合水不断流失，弱结合水先下降后上升又下降，自由水略有增加；内部微观结构观察显示，冷冻新疆馕坯出现明显的空洞与凹痕；蛋白质内部β-折叠含量降低，β-转角含量增加，有序的蛋白质二级结构变得松散、无序；同时，反复冻融也会导致冷冻新疆馕坯烘焙特性降幅增大，包括馕坯比容降低、硬度升高、综合感官评分降低等，储运过程中冷冻新疆馕坯冻融频次不宜超过4次。     

皮蛋风味物质的测定

采用固相微萃取法,结合气相色谱-质谱（GC-MS）技术对减压法制作的皮蛋挥发性风味物质进行了分析检测,并与市售皮蛋的风味物质进行了对比研究。减压法皮蛋的加工条件为：温度23℃,真空度-0.06 MPa,抽空时间10 h。结果表明：在检出的48种减压法皮蛋的挥发性风味物质中,有贡献的主要挥发性物质为2-甲基环戊醇、1-辛烯-3-醇、苯甲醛、1-甲基环庚醇、2,6-二叔丁基对甲基苯酚等;而检出的28种市售皮蛋的挥发性风味物质中,有贡献的主要挥发性物质为1,2,5-三甲基吡咯、2-甲基环戊醇、4-氨基吡啶、1-辛烯-3-醇、2-乙基-6-甲基吡嗪等;减压法皮蛋与市售皮蛋相比,在挥发性风味物质组成及其相对含量上均存在着明显差异,不但证实了减压法加工皮蛋的可行性,且发现减压法皮蛋风味比市售皮蛋要好,醇香味更浓厚,这与嗅觉判断和品尝评定的结果相符。     

宁夏滩羊肉质量属性及与内蒙古羊肉品质差异分析

以察哈尔羊、苏尼特羊和市售羊肉作为对照,对滩羊肉蛋白质、粗脂肪、水分、脂肪酸、氨基酸、游离氨基酸、解冻损失、主体风味特征、色泽、挥发性有机物,以及熟制羊肉的主体风味和滋味特性进行分析。结果显示,在营养属性方面,察哈尔羊肉蛋白质含量最高(P0.05),市售羊肉蛋白质含量最低;苏尼特羊和察哈尔羊肉粗脂肪含量最高,市售羊肉粗脂肪含量最低;市售羊肉水分含量最高,苏尼特羊和察哈尔羊肉水分含量最低;苏尼特羊和市售羊肉必需氨基酸含量最高,且以苏尼特羊肉必需氨基酸与非必需氨基酸含量比值最大(P0.05);察哈尔羊肉脂肪酸含量最高(P0.05),市售和苏尼特羊肉脂肪酸含量最低。察哈尔羊肉解冻损失较低(P0.05),苏尼特羊肉解冻损失较高。在感官品质方面,滩羊肉颜色值优于其它样品,且冻融后得到增强;各样品及其熟制品均具有独特的风味特征,通过主成分可区分生鲜样品;熟制样品中,除市售羊肉和察哈尔羊肉风味相似外,其它样品间也可通过主成分进行区分;醛类是羊肉风味呈现的主体物质,滩羊肉中甲氧基-苯基-肟含量较高,熟制滩羊肉苦味较为明显。结论:综合营养属性、理化性质和感官特征可以对羊肉进行差异化分析。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.