速冻山药热烫工艺研究

对山药的速冻预处理工艺进行了研究。在实验中,以清水为热烫液,通过测定Vc的含量、可溶性固形物的含量、过氧化物酶和多酚氧化酶的活性这四个指标来确定最佳的热烫时间和温度。同时对经热烫和不经热烫两种不同处理的山药在冻藏过程中的色泽变化进行了评价。研究表明,速冻山药必须进行热烫处理以使酶失活。最佳的热烫时间和温度为60s和90±1℃。     

速冻芦笋的热烫工艺条件研究

对速冻芦笋的热烫工艺条件进行了研究。结果显示，热烫因子笋径(A)、热烫温度(B)和热烫时间(C)对芦笋热烫效果影响的主次顺序为A＞B＞C；笋径对多酚氧化酶(PPO)和过氧化物酶(POD)活性有极显著的影响，对芦笋烫后的感官品质有显著影响；热烫温度和时间对POD活性有显著影响。芦笋热烫的适宜条件范围为茎粗0．8—1．4cm，热烫温度88—95℃，热烫时间为2—3min。热烫最佳处理组合为A2B3C1。     

生姜速冻前热烫工艺的实验研究

对速冻籽姜冻结前的热烫工艺进行了研究,分析了漂烫温度、时间对原料过氧化物酶活性、Vc含量及感官品质带来的影响,确定了漂烫工艺的最佳参数。     

阳春长山药热泵干燥工艺初步研究

采用热泵干燥技术对阳春长山药进行干燥试验研究,以热烫处理、切片厚度和干燥温度为试验变量,通过对干燥后山药品质进行分析,确定最佳工艺参数为:新鲜物料切片后直接浸泡清水无需进行热烫处理,切片厚度6 mm,热泵干燥温度60℃,干燥时间3 h~4 h,可获得较好的山药干制品。     

甘蓝复合汁工艺参数的确定

利用脱水蔬菜厂的甘蓝下脚料,经超滤澄清与苹果汁复合,开发出一种甘蓝、苹果复合汁饮料.通过研究不同热烫时间、温度对还原VC和不同酶解条件(酶用量、酶配比、pH值、时间和酶解温度)对出汁率与粘度的影响,采用正交试验确定了最佳酶解工艺为:质量分数0.06％的纤维素酶用量,物料:酶质量比30:1,pH值5.5,酶解时间40 min,温度45℃.     

甜玉米速冻前热烫工艺研究

对甜玉米速冻前热烫工艺进行了研究,通过PPO、POD等酶活性、可溶性糖和Vc等指标的检测分析和感官评价,探讨了水煮热烫处理、蒸气热烫处理和微波热烫处理等热烫处理方式、热烫处理时间等因素对速冻甜玉米品质的影响。试验结果表明,适宜的热烫处理工艺(蒸气热烫20min)能减少可溶性糖和Vc的损失,同时钝化PPO和POD酶活性,提高速冻甜玉米的品质。     

紫山药香菇营养酱的开发研制

以紫山药和香菇为主要原料,开发研制富含功能性成分的营养酱。通过单因素试验和正交试验确定了热烫温度、热烫时间、紫山药块和香菇块大小、大豆酱的加入量、紫山药和香菇质量比的最佳方案。结果表明:以热烫温度90℃、热烫时间60s、紫山药和香菇切块大小0.5×0.5×0.5cm~3、大豆酱加入量20%、紫山药和香菇质量比1∶2为最佳工艺配方。经测定,此工艺配方条件下酱体中含有蛋白质19.5g/100g、脂肪6.8g/100g、多糖1.56g/100g。可知在此条件下能得到高蛋白、低脂肪、保健价值高、口感良好、香味浓郁的紫山药香菇营养酱。     

高压二氧化碳技术速冻香菇工艺

采用高压二氧化碳技术(high pressure carbon dioxide,HPCD)对香菇进行速冻,以期解决国内食用菌速冻技术存在的能耗大、成本高的问题。在原料热烫钝酶的基础上,通过单因素试验和正交试验,并结合速冻产品感官评价对工艺条件进行优化。结果表明:HPCD速冻香菇最佳工艺参数为处理釜初温6℃、处理釜设定压力7MPa、卸压时间4min,且卸压时间为影响速冻产品品质的最显著因素。     

速冻蔬菜热烫处理的优化和节能

大多数速冻蔬菜必须经过热汤处理以保证其在冻藏期间质量的稳定性。但是热烫易引起蔬菜的色、香、味和质地的变化。目前蔬菜的热烫终点以过氧化物酶作为指示剂来确定。有关研究表明，以过氧化物酶的指示剂会导致某些蔬菜热烫过度，因此必须寻找对这蔬菜更合适的酶作为指示剂，以便优化热烫处理。在速冻蔬菜的热烫过程中要消耗大量的能量 和水，有一种热烫－冷却组合器可较好地解决蔬菜热烫过程的节能、节水问题。     

脱水海芦笋的护色工艺研究

研究了不同Na2CO3质量分数、浸泡时间、过氧化酶相对酶活、热烫时间、含盐量对脱水海芦笋护色效果的影响,通过单因素和正交实验,对脱水海芦笋的护色工艺进行了研究.结果表明:海芦笋在质量分数为1%的Na2CO3溶液中按料液质量体积比1 g∶8 mL浸泡15 min取出后,在95～100 ℃沸水浴中热烫7 min,此工艺的护色效果最佳.     

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