3种方法腌制咸蛋理化性质的对比

咸鸭蛋是我国传统再制蛋之一,优质咸蛋具有蛋清洁白不咸、蛋黄松沙出油的特点,但咸蛋加工周期长,品质不太稳定。该研究引入真空减压智能腌制设备加工咸蛋,并与泥包法和常压水淹法传统咸蛋加工方法进行对比,研究3种腌制方法对咸蛋理化性质的影响。测定腌制过程中的蛋增重、蛋黄指数、蛋黄硬化率、咸蛋的盐含量、蛋黄出油率、咸蛋质构与蛋黄风味物质。结果显示,真空减压法在12 d即可腌制出成熟的咸鸭蛋,而泥包法需要22 d,常压水腌法需要32 d。真空减压法在较短时间内就可达到与泥包法和常压水淹法腌制咸蛋的品质效果,其最终蛋黄指数、蛋黄硬化率、质构和风味物质结果均相当,达到咸蛋成熟度和质构指标以及具有特有的咸蛋风味。泥包法和常压水腌法腌制的咸蛋蛋清盐含量分别为5.32%和5.40%,口感较咸;真空减压腌制的咸鸭蛋蛋清的盐含量为4.60%,蛋黄盐含量为1.98%,达到适宜口味,整体口感最好。真空减压水腌法腌制得到的咸鸭蛋出油率(47.5%)略高于常压水腌法和泥包法(分别为46.1%和43.9%)。综上,与泥包法和常压水腌法相比,真空减压水腌法加工咸蛋可大大缩短腌制周期,且咸蛋产品的咸度适宜、出油率高,表明真空减压技术可用于咸蛋快速生产加工。     

泥腌、水腌咸蛋的理化指标和滋味品质差异分析

目的 研究单个泥腌与大缸水腌加工咸蛋品质的差异。方法 在18 ℃恒温下、用25.5% (m/m)的盐水水腌和25%的盐泥泥腌咸蛋, 测定腌制过程中咸蛋含盐率、含水率、游离氨基酸、感官评价等指标, 分析泥腌、水腌咸蛋盐分渗透规律、咸蛋含盐含水与感官品质间相关性、氨基酸味道强度值与滋味品质间的关系。结果 水腌咸蛋25 d成熟, 蛋白含盐率4.99%、蛋黄含盐率1.18%, 蛋内进盐量1.87 g, 盐利用率8.68%; 泥腌蛋35 d成熟, 蛋白含盐率3.53%、蛋黄含盐率1.87%, 蛋内进盐量1.48 g, 盐利用率38.95%。咸蛋的R值(蛋白或蛋黄的含盐含水比)、Q值(蛋黄与蛋白的平衡系数)、N值(蛋白蛋黄含盐比)均与感官品质有显著相关性(P＜0.05)。结论 单个泥腌制作的咸蛋蛋白不咸、蛋黄咸鲜, 品质更好, 其盐分利用率高于水腌方式。咸蛋的R值、Q值、N值可作为评价咸蛋综合感官品质和成熟度的定量指标。     

脉冲减压腌制低盐风味咸蛋及黑圈抑制剂开发

以新鲜鸡蛋为原料,运用真空脉冲减压水腌法,探究腌制液配比、腌制时间等对咸蛋品质的影响,采用抗氧化剂茶多酚与金属螯合剂葡萄糖酸钠作为防黑圈剂,探究在真空脉冲减压水腌法下两者抑制咸蛋黑圈的可行性及抑制效果,结果发现在42℃的腌制环境下,将鸡蛋放入盐度为24%的五香腌制液中腌制5 d,再放入盐度16%的五香腌制环境中腌制2 d,腌制成熟时间最短为7 d,极大缩短了腌制时间,咸蛋蛋黄出油率为（64.73±1.98）%,蛋清的盐含量为（4.05±0.06）%,蛋黄盐含量为（1.36±0.02）%,风味物质含有醇类、烃类、酮类、酸类和酯类,酯类物质种类及含量增加,产品为低盐风味咸蛋。复配的腌制助剂（1%茶多酚+4%葡萄糖酸钠）较单一腌制助剂预防黑圈的效果较好,在质构分析与感官评价表现也较好。     

负压快速腌制咸蛋研究

以鲜鸭蛋为原料,采用盐水腌制法,探讨了负压处理加工咸蛋的方法以及腌制过程中几个重要理化指标的变化规律。试验结果表明:负压处理腌制鸭蛋蛋白和蛋黄的氯化钠含量、蛋黄指数比对照组上升快。经检测,负压处理腌制的咸蛋理化指标和微生物指标均符合无公害食品-咸鸭蛋(NY 5144—2002)标准要求。     

低盐咸蛋的腌制工艺及其品质研究

提出一种两段腌制法制备低盐咸蛋的方法,分别对两段法腌制过程中咸蛋蛋白和蛋黄的水分含量、盐分含量进行实时检测,考察腌制结束时蛋黄的出油率,并且对咸蛋品质进行综合感官评定。结果表明,先使用19%盐水再换用3.5%盐水的两段法腌制工艺,咸蛋产品中蛋白盐分含量为3.64%,比传统法腌制产品蛋白盐分含量降低51.21%,口感适宜;蛋黄含盐量为0.94%,略低于传统法腌制的1.23%;蛋黄脂质渗出率为67.73%,与传统法腌制的69.22%基本相当。该腌制工艺不仅可解决传统咸蛋蛋白盐分过高、口感过咸的问题,同时也可保证蛋黄松沙出油,从而获得高品质的低盐咸蛋。     

烹饪用咸蛋黄腌制工艺研究

以新鲜鸡蛋蛋黄为原料,对烹饪用咸蛋黄腌制工艺参数进行优化.采用单因素试验探究腌制时间、温度及食盐、白酒添加质量分数对咸蛋黄出油率、色度值的影响;利用响应面分析优化高出油率咸蛋黄的腌制工艺参数.试验结果表明,咸蛋黄的出油率和色度值随食盐、白酒添加质量分数、腌制温度、时间的增加呈现先增大后减小的趋势.食盐添加质量分数1.6...     

稻秸灰水提物对咸蛋黄理化特性的影响

本研究将稻秸灰水提物与食盐混合配制腌制液腌制咸蛋,并比较了食盐水腌制和水提物腌制对咸蛋黄含盐量、含水量、出油率、流变特性、质构特性、蛋白结构的影响,研究表明:由于盐类的进入和油脂渗出,蛋黄的质构特性如:硬度、胶黏性、咀嚼性呈先增大后减小的趋势(p0.05),其中水提物组硬度从272.89 g增至最大值458.65 g后又逐渐降至228.87 g。流变学结果显示蛋黄弹性模量和粘性模量均显著增大。水提物组蛋黄蛋白二级结构中α-螺旋在25d时显著减少至12.36%(p0.05),β-折叠在25d时显著增大至41.71%(p0.05)。SDS-PAGE表明水提物的加入不会影响蛋黄蛋白质肽链结构。水提物组咸蛋黄的出油率达到20.12%,较盐水组高,出油率是评价咸蛋品质的一个重要指标。此研究既优化了传统草木灰包裹法工艺又保持着草木灰咸蛋的优良品质,为咸蛋腌制提供了一种新思路。     

腌制条件对熟制咸鸭蛋蛋黄组织形态及组成的影响

为探索咸鸭蛋腌制条件对熟制后蛋黄组织形态及组成的影响，以期减少熟制咸鸭蛋蛋黄中的硬芯含量，通过称量法、原子火焰吸收光谱分析、凯氏定氮法、差示量热扫描分析、红外光谱分析和扫描电子显微镜观察等方法对不同腌制浓度和时间下咸蛋黄不同部位理化性质以及生熟咸蛋黄微观结构的不同进行分析。结果表明，蛋黄硬芯从鸭蛋腌制的第2周出现，随着腌制时间延长，硬芯逐渐变大，腌制完成后占蛋黄总质量的33.64%～44.80%，水分含量约为21.47%～23.49%。硬芯的Na+含量在10.66～11.47 mg/g之间。腌制完成后，蛋黄外部的游离脂肪含量约为34.79%～36.34%，与外部相比，硬芯的游离脂肪含量更低，约为17.71%～27.90%，且随着腌制液盐浓度的上升而增加。腌制后蛋黄硬芯蛋白质含量上升至30%以上，高于外部。蛋黄经加热后，硬芯部分蛋黄微粒颗粒度较小，且形成间隙较小的连续结构。盐分渗透的先后顺序导致蛋黄中不同部位在组织结构和组成成分的差异，这些差异导致了熟制后蛋黄硬芯及外部的差别，且较高的腌制时间和浓度均会加剧硬芯的形成。在15%盐浓度条件下腌制4周后，得到的成熟咸蛋黄在熟制后硬芯含量较少，...     

减压法快速腌制咸蛋及蛋黄中脂肪酸变化

将减压技术应用于咸蛋的传统盐水浸泡法中,达到了明显缩短咸蛋腌制周期的目的。通过单因素试验和正交试验分析,测定各组蛋在腌制过程中的蛋黄色度、指数、蛋清和蛋黄含盐量、咸蛋合格率以及感官评分,得到减压法腌制咸蛋的最优工艺条件是:真空度为-0.09 MPa,温度为23℃,每天维持一定真空度的时间为23.5 h。利用GC-MS技术测定鲜鸭蛋和所腌制咸蛋的蛋黄中的脂肪酸,发现两者之间脂肪酸的种类没有发生变化,相对含量有所不同,腌制后棕榈酸由7.707%上升到12.910%,亚油酸由6.166%减少到3.835%,顺式-十八烷酸由16.510%增加到31.620%。     

咸蛋黄快速腌制剂的优化研究

蛋清和蛋黄分离后用盐水直接腌制蛋黄,不仅可以达到快速腌制蛋黄的目的,还可以大大减少咸蛋清的浪费。该研究采用单纯形格子法对咸蛋黄的快速腌制剂配方进行研究,结果表明,食盐浓度对咸蛋黄的咸度影响最大,白酒对咸蛋黄风味起到重要作用,磷酸二氢钠和卡拉胶对咸蛋黄的出油率贡献较大。综合考虑成本与工艺要求等问题,确定咸蛋黄的腌制剂配方为:食盐70%,卡拉胶2.5%,磷酸二氢钠7.5%,白酒20%,在该条件下制备的咸蛋黄的含盐量、感官评价和出油率分别为2.10%、15.10和41.56%,与理论预测值的相对误差均在±1%以内,说明利用该方法建立的模型在实践中进行预测是可行的。     

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