不同屠宰工艺(剥皮和烫毛)对猪胴体表面微生物的多样性影响及关键点的控制研究

应用变性梯度凝胶电泳(Denaturinggradientgelelectrophoresis(DGGE))和经典微生物培养相结合的方法研究了剥皮和烫毛工艺中猪胴体表面污染的微生物数量和细菌多样性的变化以及3.5%乳酸处理后细菌总数和大肠菌群的变化。结果显示:不同猪胴体屠宰工艺中的微生物种类并不完全一致,微生物的污染多是由于前期的屠宰工艺引入;与剥皮工艺相比,烫毛后污染的微生物种类多,初始污染程度也较为严重;乳酸处理显著降低了剥皮工艺中的细菌总数,使出库猪胴体表面细菌总数降低到2.95logCFU/cm2,完全达到HACCP微生物的控制要求,但是没有降低烫毛工艺出库时的细菌总数,因此对不同的屠宰工艺应采取不同的关键点控制措施。     

基于不同提油工艺的薏米糠重金属流向及安全评价

采用超临界CO_2萃取法(SPE)、正丁烷亚临界浸出法(BSE)和石油醚索氏抽提(PSE)3种工艺提取薏米糠油,检测As、Pb、Cd、Hg、Cu、Zn和Mn在薏米糠、薏米糠油及薏米糠粕中的含量。结果表明:3种提油工艺中,超临界CO_2萃取法的薏米糠油中Hg、Cu、Zn和Mn含量较低,尤其Cu含量显著低于其他两种工艺,而石油醚索氏抽提的薏米糠油中Hg、Zn和Mn含量最高;3种提油工艺中,薏米糠油重金属迁移率均以Hg最高,分别达24.47%、31.91%和89.36%,其次为Cu,分别达为14.65%、23.79%和16.83%,而其余重金属迁移率较小;经重金属安全评价,除超临界CO_2萃取法和正丁烷亚临界浸出法的薏米糠油Pb为轻度污染外(污染指数分别为1.074和1.017),其余重金属均在安全范围内;3种薏米糠粕中均存在As、Pb、Cu和Mn污染。     

锯屑亚铵法制浆工艺条件探讨

在大力倡导节约原料,降低成本,减少污染的制浆方法下,本实验采用污染较小的亚铵法对锯屑进行蒸煮,找出了较佳的蒸煮工艺条件。其较佳蒸煮工艺条件为:最高蒸煮温度165℃,亚铵用量(18—20)%,液比1:2.5,尿素用量2%.AQ用量0.05%。在此条件下,所得浆耐破度165 kPa,裂断长4 768 m.撕裂指数8.7 mN·m2·g-1。     

杠板归中提取天然酒石酸氢钾的方法研究

杠板归(Perfoliate Knotweed)是蓼科植物,味酸,富含酒石酸氢钾(potassium hydrogentartrate)。杠板归广泛分布于我国南北各地,为了避免资源浪费,合理利用天然资源,研究了用物理工艺方法提取杠板归中天然酒石酸氢钾,提取收率为85%,含量达到99.51%。提取方法简便,无任何污染,是一种提供天然食品添加剂酒石酸氢钾的有效方法。     

皮革工业鞣前工段可持续发展的生态友好废物处理方法

皮革工业生产过程中产生的皮蛋白类材料和大量的固体和液体废弃物造成的污染,需要通过可持续的清洁技术来解决。本文综述了生态友好面临的各种挑战和皮革生产中减少污染的主要成就。讨论了原皮保存、浸水、脱毛等工序中的清洁技术方法。使用化学和生物制剂的清洁保存技术,已经发展到在很大程度上减少了皮革生产过程中盐的污染问题。通过强化工艺操作有助于化学品更好的吸收和解决污染载荷。酶脱毛可降低40%的COD和50%的BOD。     

减少铬用量

云南蒙自皮革厂自去年六月以来,针对轻革鞣制中铬的耗量高、污染重的问题,改革工艺,先后对黄牛正面革、牛油浸革、山羊正面革、山羊鞋面革等产品进行了试验并逐步投入生产。实践证明,浸酸后加10%的铬液初鞣(计红矾2.5%),再用5%的铬液进行复鞣的工艺,是成功的。这个工艺较原工艺有很多好处:(1)减少了红矾用     

实验制粉去除小麦中脱氧雪腐镰刀菌烯醇(DON)的研究

采用自然污染脱氧雪腐镰刀菌烯醇(DON)毒素不同程度的9种小麦为材料,通过检测其经实验制粉工艺得到麸皮、细麸、不同出粉点面粉包括最后统粉的DON含量,探索小麦实验制粉工艺去除DON的效果。结果表明:经过小麦实验制粉工艺后,能够重新分配小麦中的DON毒素,存留在面粉中的DON总量仅为原来小麦的31.03%～50.39%,并主要分布在小麦的表皮中,在小麦胚乳中也呈从内到外逐渐升高。制得面粉统粉中DON含量减少23.67%～58.97%,心磨粉最高能减少70.51%。小麦籽粒DON含量与制得面粉中DON含量之间呈幂函数回归关系,回归方程为y=0.498x1.206(R2=0.991),随着DON污染程度越低,DON含量减少率越大。以上实验证明,小麦制粉工艺是一种有效的去除小麦中DON毒素的方法。     

逆流提取工艺中浆料浓度对黑液提取率的影响

为定量探究碱回收工艺中浆料浓度对黑液提取率的影响,本研究以烧碱法红松浆和黑液为原料,采用逆流提取工艺,对不同浆浓的黑液提取率及浆料洁净度进行研究。结果表明,相比于15%浆浓,35%浆浓的黑液提取率从75.61%显著增加到98.19%。高浓提取不仅能有效促进碱回收,还可明显提高纸浆洁净度。浆料经过三段提取后35%浆浓的总残碱去除率、COD_(Cr)和BOD_5提取率分别为96.01%、95.0%和98.0%。浆中残余COD_(Cr)和BOD_5的大幅降低,不仅从源头上减少了污染物进入后续漂白和造纸工艺,还可提高漂白效率、降低漂白废水的污染负荷和毒性。     

发酵法制备罗非鱼皮胶原蛋白肽的工艺的研究

目的:研究利用枯草芽孢杆菌进行发酵法生产罗非鱼皮胶原蛋白肽的制备工艺。方法:以罗非鱼皮和水为原料,接入枯草芽孢杆菌进行发酵,对罗非鱼鱼皮浓度、装液量、接种时间、接种量、发酵时间进行了考察,通过单因子实验和正交实验优化确定了最佳发酵工艺。结果:最佳发酵工艺为:罗非鱼鱼皮含量为3%,装液量为90mL/250mL,接种量为5%,接种时间为14h,发酵时间为52h。并且在此发酵工艺下,罗非鱼鱼皮蛋白的水解度高达36.88%。结论:采用枯草芽孢杆菌发酵法制备罗非鱼皮胶原蛋白肽,工艺简单、成本低、不污染环境、水解度高,是值得推广的制备胶原蛋白肽的方法。     

2007—2014年绍兴地区蔬菜中重金属污染调查

目的了解绍兴地区蔬菜中铅、镉和总汞的含量水平及污染程度,为制定蔬菜中重金属污染控制措施提供依据。方法 2007—2014年在绍兴地区7个调查点的农贸市场、超市等地点随机抽取7类共984份蔬菜样品,采用国家标准方法检测蔬菜中铅、镉和总汞的含量,按GB 2762—2012《食品中污染物限量》统计超标情况。采用单因子污染指数和内梅罗综合污染指数评价蔬菜中重金属污染程度。结果 984份蔬菜样品铅、镉和总汞的检出率分别为68.4%(673/984)、92.0%(905/984)和37.6%(370/984),超标率分别为2.9%(29/984)、1.2%(12/984)和5.8%(57/984),平均值分别为0.040、0.017和0.004 0 mg/kg;2009—2011年蔬菜中总汞超标率较高,超标率分别为17.3%(19/110)、24.7%(19/77)和10.1%(12/119);鳞茎类蔬菜中铅和镉超标率分别为14.0%(6/43)和11.6%(5/43),均为各类蔬菜中最高。所有种类蔬菜的综合污染指数均小于0.7。结论绍兴地区蔬菜中重金属总体污染水平不高,但部分蔬菜中重金属污染相对较突出,应继续加强监管和控制。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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