北京市海淀区市售肉制品和腌制蔬菜中亚硝酸盐含量及居民知信行调查

目的了解北京市海淀区市售肉制品和腌制蔬菜中亚硝酸盐含量,并调查该地区居民对亚硝酸盐的知识、态度以及对含有亚硝酸盐食物的摄入情况。方法采集市售肉制品和腌制蔬菜样品34份,经过预处理后采用分光光度法检测样品中亚硝酸盐含量。采用自拟调查表和偶遇抽样面访采集数据,使用Epidata 3.1对问卷进行平行双录入,使用SPSS 20.0进行统计分析。结果样品中亚硝酸盐含量均在食品安全国家标准允许范围内,平均亚硝酸盐含量从高到低依次为香肠、酱卤肉、腌腊肉、腌制蔬菜,差异具有统计学意义(P0.05)。受访者对亚硝酸盐的危害及亚硝酸盐含量高的食物认识不足,仅有54.5%的人表示会有意减少食用亚硝酸盐含量高的食物;受访者在上个月内食用肉制品及腌制蔬菜的量和频率不高。结论北京市海淀区居民通过肉制品及腌制蔬菜摄入过量亚硝酸盐的风险很低,可以安全食用。     

腌腊肉制品的保鲜技术

腌腊肉制品是指肉类原料经盐腌制,烘烤或凉挂加工而成的一类肉制品,需经烹饪熟制之后才能食用。一般包括香肠、香肚、火腿、板鸭等,其卫生质量问题主要为亚硝酸盐残留、脂肪氧化酸败和霉变。只有弄清各种食品添加剂的用途和作用机理,掌握正确的使用方法,并且配套使用先进的包装技术等措施,才能够有效地保证腌腊肉制品的质量,并使添加剂含量符合国家相关的食品卫生标准。1亚硝酸盐的正确使用1·1亚硝酸盐的作用及危害在腌腊制品的加工过程中,常常加入硝,包括硝酸盐和亚硝酸盐。在腌腊肉制品的生产过程中使用硝,作用主要表现在以下三个方面。(…     

果蔬对亚硝酸盐清除作用的研究进展

发色剂亚硝酸盐对腌腊肉制品有护色、改善风味、防止腐败和预防肉毒中毒的重要作用。但是肉制品中过量添加发色剂,可致亚硝酸盐急性中毒,同时亚硝酸盐也是形成强致癌物亚硝胺的前提。因此,清除亚硝酸盐或阻断亚硝胺的合成是促进膳食健康的有效途径之一。将近年来有关果蔬清除亚硝酸盐和阻断亚硝胺形成的研究进展进行综述,为腌腊肉制品的合理搭配、科学烹饪提供依据,对提高腌腊肉制品食用安全具有重要意义。     

腊肠加工过程中N-亚硝胺形成因素及其测定方法的研究

正硝酸盐或亚硝酸盐在腌腊肉制品中很重要,它具有发色、提高风味、抗氧化以及抑菌等作用,但它却会与肉品中蛋白质分解的二级胺形成N-亚硝胺。N-亚硝胺是一类致癌物质,若腌腊肉制品不使用亚硝酸盐或硝酸盐,则可能会有更大的危险,因而目前没有找到理想替代物的情况下仍然使用它,那么研究N-亚硝胺的形成因素并控制其形成就成为世界各国研究的热点。研究了腊肠中N-亚硝胺形成的主要影响     

食品中亚硝酸盐检测方法的研究进展

亚硝酸盐广泛存在于肉制品、腌制食品和蔬菜等食品中。由于亚硝酸盐有一定的毒性，摄入过多会危害人体健康。因此，应用快速可靠的方法检测食品中的亚硝酸盐尤为重要。本文总结了各类食品在检测前的预处理方法，综述了近年来国内外检测食品中亚硝酸盐的主要方法和研究进展，总结分析了光度法、色谱法、化学发光法、电化学法、滴定分析法的原理、检测限和优缺点，旨在为科学准确地检测各类食品中的亚硝酸盐提供参考依据。     

低盐腌腊瘦肉条生产技术

近年来传统腌腊肉制品产业与其他肉类食品产业相比,传统腌腊肉制品产业仍发展缓慢,区域性强,产业化水平和加工技术仍然较低。其中突出问题是传统腌腊肉制品盐分含量高、水分含量低、生产周期长。主要介绍我国目前传统腌腊肉制品现况和存在的问题,并以R公司的猪肉瘦肉条为例,探讨解决传统腌腊制品上述问题的研发方向和对策,利用天然防腐剂、注射和滚揉工艺,加速腌制速度,缩短生产周期,降低产品的盐含量。     

盐水火腿加工中影响亚硝基化合物生成因素的研究

在肉类加工中亚硝酸盐和硝酸盐是很常用的食品添加剂,可以改善肉的色泽和风味,延迟脂肪的氧化和酸败,并且抑制肉毒梭状芽孢杆菌的繁殖,从而延长肉制品的货架期。但20世纪70年代人们发现了这些添加剂的危害:它们可以和氨基酸等含氮化合物反应生成致癌物-亚硝胺。而且亚硝酸盐在胃液环境下也可以形成亚硝胺。本文主要研究盐水火腿加工过程中,腌制时间、煮制时间和煮制温度以及亚硝酸钠和抗坏血酸钠的添加量对最终产品中残留的亚硝酸钠和生成的亚硝胺含量的影响,以期加工出更安全卫生的肉制品。研究表明,腌制时间控制在24h,亚硝酸钠的添加量为0.12g/kg,抗坏血酸钠的添加量为0.64g/kg,而煮制温度为85℃,煮制时间为1h(肉块大小为250g)时产品既能保持良好的色泽,又能使亚硝基化合物的含量降到最低水平。     

鸡肉制品腌制过程中盐毒力的监测

随着人民生活水平的提高,人们对于食品安全的要求也在不断增加,在这个人人号召健康饮食的年代,人们往往谈腌制品色变。这是由于蔬菜腌制的过程中产生亚硝酸盐,肉制品的腌制过程中为了防腐提色也会加入适量的亚硝酸盐,食用过量的亚硝酸盐就容易引起人体中毒,因而对食品的腌制过程进行毒力监测很有必要。本文选用鸡肉制品来监测其腌制过程中的盐毒力。     

第一章 吃的基础课⑤

正提防亚硝酸盐蔬菜在生长过程中不可避免会积累下一定量的硝酸盐,硝酸盐在一定条件下很容易转化成亚硝酸盐。而亚硝酸盐在一定条件下(比如在胃里这种反应就很容易进行)进一步与蛋白质分解产物合成亚硝胺,亚硝胺则具有一定的致癌作用。为了减少致癌物亚硝胺产生,应尽量少吃或不吃腌制的蔬菜(如酸菜、咸菜)、长时间储存(不新鲜)的蔬菜、缺乏水分的蔬菜(如春季野菜)等。值得注意的是,长时间浸泡     

青梅腌制品中亚硝酸盐形成的抑制研究

青梅是一种营养价值丰富的水果,但青梅多被腌制成青梅制品来食用,在腌制过程中又容易形成亚硝酸盐。为了减少青梅腌制品中亚硝酸盐的含量,首先研究不同青梅腌制品中亚硝酸盐含量;然后确定青梅制品中亚硝酸盐形成的抑制物;再以其中一种腌制品为代表进行抑制因素最佳效果研究。实验结果表明:不同青梅腌制品中亚硝酸盐的含量不同,新鲜青梅盐腌梅糖腌梅青梅酒,说明青梅在腌制后亚硝酸盐都有增加;适量Vc、茶叶、乳酸菌均能降低青梅腌制品中亚硝酸盐的含量,其中Vc降解效果最好;以糖腌梅为例,腌制时加入5 g茶叶、100 mg Vc、0.45 g乳酸菌得到的糖腌梅亚硝酸盐含量仅为0.87 mg/kg,比新鲜青梅还低(新鲜青梅0.98 mg/kg)。     

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.     

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.     

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.     

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.     

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.     

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.     

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.