如何做好蒸煮包装袋的蒸煮试验

蒸煮包装袋的质量检测项目,除了普通复合包装袋通用的指标外,最关键的是蒸煮试验,检测蒸煮前后其性能的变化。蒸煮试验的必需设备是高温蒸煮锅,本文就向大家介绍一下高温蒸煮锅及蒸煮试验操作工艺。高温蒸煮锅的结构高温蒸煮锅必须是带有反压装置和强制冷却装置的设备。按加热方式来分,有过热蒸汽加热和电加热两类,不管是哪一类,又有静止式和回转式两种:按接触方式来分,有水浸式和汽浴式两种。以过热蒸汽加热的汽浴式高温蒸煮锅     

提高药液利用率的蒸煮锅循环加热结构

<正>现有立式蒸煮锅在蒸煮时,将蒸煮的原料和药液加入蒸煮锅后,仅仅是往蒸煮锅中通入蒸汽进行蒸煮,蒸汽虽然对药液具有搅拌作用,但搅拌效果不佳,药液未完全被利用,从而导致蒸煮效果不佳。在此提供一种能提高药液利用率,从而使蒸煮效果更好的蒸煮锅循环加热结构。如图1和图2所示,蒸煮锅循环加热结构包括蒸煮锅,蒸煮锅上端和下端均设有进液口,其中,还设有环形滤网、滤网架、连接头、循环泵和药液接管,滤网架     

置换蒸煮实验装置的设计

介绍了所设计的置换蒸煮实验装置的基本原理、系统构成及特点,本设计解决了以往置换蒸煮实验装置易堵塞、加热不均匀、取样难等问题。     

红麻全秆烧碱——蒽醌法蒸煮

本研究认为，烧碱-蒽醌（AQ）法比硫酸盐（KP）法更适合于红麻全秆原料的蒸煮。同时，在实验室条件下，模仿连续蒸煮的实际生产过程进行了连续蒸煮的研究。1实验方法1.1原料化学成分分析实验所用原料取自湖南沉江“青皮三号”。原料化学成分分析均按有关国标进行。l·2间歇蒸煮采用8罐甘油浴蒸煮锅蒸煮，装料809（绝干计入纸浆得率、Kappa值和黑液残碱的测定均按标准方法进行。1．S连续蒸煮预浸在水浴中进行，蒸煮采用8罐甘油浴蒸煮锅。先将甘油加热到规定温度，放入已装好料片的蒸煮锅进行蒸煮，到规定时间后取出蒸煮锅并迅速冷却，冷却…     

加工食品用的新型蒸煮系统

本文主要论述加工食品的有效连续加热、杀菌及冷却方法,即则武蒸煮系统;该系统装置是应用静止型混合搅拌器的混合原理及优点研制而成的。它可对低粘性流体、高粘性流体、热敏流体及合固体成分的流体进行短时间的加热、杀菌或蒸煮及冷却处理。     

苏联酒精生产的连续蒸煮

苏联酒精厂现在采用的原料蒸煮方法，有连续与间歇（单锅和三段蒸煮）两种。单锅蒸煮仅在很少数老的小型酒精厂中保留。苏联在1945—1950年开拓了三段蒸煮，它将原料的蒸煮与蒸煮醪的糖化紧密结合在一起。三段蒸煮方法中亨兹蒸煮锅（即锥形锅）仍然是蒸煮的主要设备，原料的预煮加热是在单独的预煮锅中，用原料从蒸煮锅吹送到贮留罐时形成的二次蒸汽进行的。加热原料的后熟也是在单独的贮留罐中进行。该方法还保证了糖化的连续性。单锅蒸煮改为三段蒸煮能够提高生产能力12—15％，减少蒸汽消耗20—30％，每吨淀粉能多出3公升酒精。     

低能耗间歇蒸煮RDH系统

一、导言我国的制浆方法主要是硫酸盐法。传统的硫酸盐法制浆设备主要有两种:一种是蒸煮锅和蒸球等间歇蒸煮器,另一种是潘迪亚(Pandia)连续蒸煮器。我国大型制浆造纸厂的新建与改造就存在一个蒸煮器的选型问题。间歇蒸煮设备的主要优点是同一蒸煮系统能同时适用于不同原料和不同浆种,而连续蒸煮器(指卡米尔Kamyr式)的主要长处是节约能源,这里介绍一种新型的低能耗间歇蒸煮系统,可供蒸煮器选型时参考。 Rader displacement heating—Rader置换加热,简称RDH系统是Beloit公司开发的一种低能耗间歇蒸煮设备。世界上已经有若干制浆厂采用这种设备。最初采用RDH     

蒸煮锅的直接通汽加热蒸煮

国内大中型制浆造纸企业大多数采用多台立式蒸煮锅以硫酸盐法进行间歇式蒸煮制浆。在蒸煮过程中，偶尔出现间接加热循环系统故障，无法继续用间接加热法进行蒸煮。若进行抢修，则必须先把蒸煮锅内的半生浆排出，不仅造成一定的经济损失，又增加处理半生浆的劳动强度，影响正常生产。其实可以采用蒸煮锅的直接通汽加热蒸煮法对锅内的半生浆继续蒸煮，待完成蒸煮过程，浆被喷放出锅体后，再进行抢修。这种处理半生浆办法在经济上和技术上都是行得通的。蒸煮锅的直接加热蒸煮法，是由蒸锅的下底锥部的直通汽管向锅体内通入一定压力的饱和蒸汽加…     

利用蒸煮锅噴放热的二效蒸发器

本文叙述利用蒸煮锅喷出的蒸汽所加热的水来蒸发黑液中水份的二效蒸发器的安装和操作。这套装置已在某厂投产。 该厂由于增加厂纸浆产量,原有的黑液蒸发设备能力不足,于是进行多效蒸发器(每小时约蒸发90,700公斤黑液)和二效蒸煮锅喷     

造纸及相关行业专利

【申请号】01235461【发明名称】制浆蒸煮过程纸浆卡伯值在线光谱测量装置【摘要】本实用新型是制浆蒸煮过程纸浆卡伯值在线光谱测量装置。本装置中,蒸煮锅通过管道与瓦斯冷却器、蒸煮锅外循环加热器、蒸煮锅外循环泵、流动槽相连接,过滤器通过管道与取样阀、流动槽相连接,卡伯     

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