钙处理对干装苹果罐头质地的影响

采用质地多面分析方法(TPA),以清水处理为对照,研究碱性钙(氧化钙、氢氧化钙)、无机钙(氯化钙、碳酸钙、硫酸钙)、有机钙(乳酸钙、醋酸钙、丙酸钙)对干装苹果罐头质地参数(硬度、回复性、弹性指数、咀嚼性、内聚性)的影响,并对TPA参数之间及其与感官品质间的相关性进行了研究.结果表明:与对照相比,除硫酸钙以外,各处理对干装苹果罐头质地均有明显的影响,经碱性钙(氧化钙和氢氧化钙)处理的干装苹果罐头硬度适中,回复性、弹性指数、咀嚼性、内聚性、感官品质均较好.回复性、弹性指数、咀嚼性、内聚性之间的相关性均显著,硬度与感官品质之间呈显著正相关关系.表明碱性钙对干装苹果罐头有较好的作用,并保持良好的质构.     

醋豆产品的质地分析(TPA)试验研究

介绍了TPA质地分析方法及TPA质地参数的定义,并对醋豆产品进行TPA测试,探讨了测试速率、压缩距离、探头类型、两次压缩的间隔时间等条件对醋豆质地参数的影响和变化规律.在一定的检测条件下,对比了休闲型和成人型醋豆的硬度、弹性、耐咀性、内聚性和回复性的差异.对质地分析方法在醋豆口感品质的控制和快速检测中的应用有一定的参考价值.     

基于质地多面分析法对不同苹果品种果肉质构特性的分析

为了细致研究"华红"苹果贮藏期间果肉质地变化和不同苹果品种质构特性差异,本实验以套袋和未套袋"华红"苹果为试材,应用质地多面分析法定期测定贮藏期间果肉质地参数;以及以不同熟期"华红"、"华苹"、"寒富"、"红星"、"嘎拉"、"津轻"为试材,比较不同苹果品种果肉质地品质差异,同时分析各质地参数之间相关性。"华红"套袋和未套袋果肉质地参数在常温贮藏过程中变化趋势基本一致,且未套袋果肉的各项质地参数稍高于套袋的。硬度呈下降趋势,在黏附性、内聚性、弹性、咀嚼性、回复性方面,贮藏0 d的果实与48 d相比稍有升高。"华红"果肉贮藏期间质地参数变化相关性和6个苹果品种之间质地参数相关性有相似处,内聚性与弹性、回复性、咀嚼性都呈正相关,弹性与回复性、咀嚼性都呈较好地正相关,回复性与咀嚼性呈较好的正相关。不同的是,"华红"果肉硬度与黏附性、内聚性呈负相关,而不同品种之间果肉硬度与内聚性、弹性、回复性、咀嚼性呈高度正相关。不同品种之间各质地参数也进行了量化比较。综上说明本实验选用的P5探头测定的果肉内聚性、弹性、回复性、咀嚼性能反映"华红"果肉质地变化规律,适用于苹果果肉质地品质的客观评价。硬度、内聚性、弹性、回复性、咀嚼性质地参数中的一项或多项可以作为评价"华红"果肉质地和比较这6个苹果品种果肉质地差异性的重要参数。     

广式月饼感官评分与TPA参数的相关性

针对目前我国月饼品质缺乏客观性评价标准的问题,通过分析测试条件对月饼TPA参数的影响,确定月饼TPA测试的最佳条件为,测试速度5 mm/s、压缩程度75%、停留时间0.5 s、触发力5 g、半圆形样品形状;采用感官评定中的质地多面剖析方法,制定蓉沙类广式月饼感官评分细则,包括最初值、咀嚼中和剩余质地3个阶段中的外形、色泽、硬度、脆性、弹性、粘性、舌对形状的感受、破碎速率、破碎情况、水分吸收和口腔感觉共11个量化指标;通过分析感官评分和TPA参数的相关性,发现月饼的硬度、凝聚性和回复性均与其感官评分呈显著负相关(P<0.05)。由此提出以硬度、凝聚性和回复性3个TPA参数来客观评价月饼品质。     

酶解鸡肉蛋白对鸡肉肠品质的影响

在鸡肉肠中添加不同水解时间下得到的功能鸡肉蛋白,采用TPA质构测试和感官实验,研究功能鸡肉蛋白对鸡肉肠质构(脆性、硬度、弹性、内聚性、胶黏性、咀嚼性和回弹力)和感官质量的影响。结果表明,添加不同功能鸡肉蛋白的鸡肉肠的硬度、弹性、内聚性、胶黏性、咀嚼性和回弹力等质构指标值的变化趋势基本一致,都是先增大,然后减小。水解3 h得到的鸡肉水解蛋白可以使鸡肉肠的各项质构指标达到最大。水解时间为2 h~4 h的功能鸡肉蛋白相对应的鸡肉肠的外观、气味、风味和质地等感官指标分值最大,感官质量最佳。     

枣泥馅料质构参数与感官品质的相关性

针对目前枣泥馅料品质缺乏客观性评价标准的问题,通过分析测试条件对枣泥馅料TPA参数的影响,确定枣泥馅料质构仪质地分析法(Texture Profile Analysis,TPA)在探头的测试速度5 mm/s,对枣泥表面的压缩程度为50%,测试停留时间为5 s,探头对枣泥馅料的触发力为5g时,此时得到的TPA参数对枣泥馅料的测验条件最佳;通过采用感官评定中的质地多面剖析方法,制定了枣泥馅料评分细则。结合对感官评分之间的相关性进行皮尔逊分析结果得知感官评定指标的粗糙度与易碎性、硬度、紧密性之间具有不同程度的影响(皮尔逊系数r在0.9～1之间,p0.01);对TPA参数与感官评分的相关性分析得出,质构仪(TPA)分析参数中硬度、黏附性、凝聚性、咀嚼性和回复性与感官评分都在0.01水平上显著相关。由此提出以硬度、黏附性、凝聚性、咀嚼性和回复性5个TPA参数作为客观评价馅料品质的指标。     

胭脂萝卜质地特性分析研究

采用食品物性仪对重庆涪陵胭脂萝卜进行质地特性测试,分析了各质地指标间的相关性,找出了能评价胭脂萝卜质地特性的代表性指标,并和感官评定进行了相关性分析。结果表明:最佳测试条件是测试速度100mm/min、样品形变量70%、TMS 25.4圆柱形探头、触发力0.2N、回程高度15mm。在质地特性指标分析中,胭脂萝卜的硬度与脆性相关性达0.961,呈现极显著相关;咀嚼性与内聚性、回复性相关性分别达0.959和-0.893,均呈现极显著相关,而其他质地指标间未显现出显著的相关性。感官评定与质地特性的相关性分析表明,感官硬度与质地特性的硬度、脆性的相关系数分别为0.943和0.905,总体口感与咀嚼性的相关系数为0.933,均呈现极显著相关;硬度、脆性、咀嚼性指标能够反映出胭脂萝卜的感官质地品质;硬度、脆性、咀嚼性可作为胭脂萝卜最具有代表性的质地特性指标。研究结果为胭脂萝卜质地品质分析和进一步开发利用提供了帮助。     

质构分析(TPA)及测试条件对新鲜湿面品质的影响

简要介绍质构分析(Texture Profile Analysis)的方法,具体阐述TPA质构参数的含义,并对新鲜湿面进行TPA测试,研究压缩速率、压缩程度及停留时间对测试结果的影响.结果表明,压缩速率对F1及弹性影响显著,对硬度影响极显著,对内聚性、耐咀性及回复性影响不显著.而压缩程度对6个参数影响均为极显著.停留时间对F1、硬度、内聚性、耐咀性及回复性影响不显著,而对弹性影响显著.     

豆酱自然发酵过程中质地变化及相关性分析

采用质地多面分析法(TPA)对东北传统豆酱自然发酵过程中硬度,黏着性,内聚性和胶着性的变化情况进行探讨,分析了测定参数的变化与感官评价指标间的相关性,结果表明,随着发酵时间的延长,黏着性和内聚性呈上升趋势,硬度和胶着性呈先上升后下降趋势。黏着性和内聚性与感官评价指标间呈极显著正相关关系。以仪器测定参数硬度、黏着性、内聚性和胶着性为变量建立感官评定预测模型,结果表明,黏着性和内聚性对感官评价指标影响较大。     

基于质地剖面分析的干制红枣品质评价

为探索不同温度下干制红枣品质的评价方法,采用TPA分析法(质地剖面分析)和化学分析法分别测定了50(27 h)、60(18 h)、70℃(12 h)热风干燥,自然阴干(35 d)和糖心枣(ck)5种样品的质地参数(硬度、黏着性、弹性、内聚性、咀嚼性、回复性)及糖酸比,通过相关性分析并对质地参数进行聚类分析。结果表明:干制显著改变了红枣的质地性状,硬度显著降低、而黏附性显著升高(P0.05);60℃(18 h)热风干制红枣样品保持了较好的硬度、黏附性、咀嚼性、弹性和糖酸比参数,具有较好的质地性状和口感风味,优于50℃(27 h)和70℃(12 h)热风干制及自然阴干(35 d)红枣的品质。质地参数间有较好的相关性,聚类分析可实现对不同条件下干制红枣质地品质的区分,为干制红枣的质地性状等级评价提供了理论参考。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press