甘蔗混合汁无硫澄清工艺的澄清效果研究

分析无硫澄清工艺的清汁、糖浆与白砂糖理化指标,并通过T检验分析这些物料理化指标与亚硫酸法的差异显著性。同时分析无硫澄清工艺过程Ca_3(PO_4)_2、CaCO_3及单宁钙协同CaCO_3等沉淀物微观结构及吸附蔗汁胶体、色素效果,探讨无硫澄清的除杂脱色原理。结果表明,无硫澄清工艺清汁和糖浆在纯度、色值、还原糖含量等指标T检验p值均大于0.05,而清汁浊度、糖浆电导灰分及浊度的p值小于0.05,表明无硫澄清工艺与亚硫酸法工艺清汁、糖浆在纯度、色值、还原糖含量等关键指标无显著差异,在清汁浊度、糖浆浊度与电导灰分存在显著性差异;所煮制白砂糖不含SO_2,色值为46 IU,浊度21 MAU,水分0.07%,电导灰分0.024%,色值与浊度明显优于亚硫酸法(色值62 IU,浊度38 MAU,表明无硫澄清工艺完全可以满足一级白砂糖生产的工艺要求,且在色值与混浊度更具有优势。从扫描电子显微镜图可知,纯水体系生成的CaCO_3、Ca_3(PO_4)_2和单宁钙沉淀具有明显的晶体结构,晶体间存在许多空隙,且在蔗汁体系生成CaCO_3、Ca_3(PO_4)_2及单宁钙沉淀晶体间绝大多数空隙已全部或大部分被填充,特别单宁钙,空隙数量已显著减少,甚至观察不到,表明上述沉淀物生成时会同步吸附混合汁的胶体、色素等形成共沉淀,从而将它们除去,胶体去除率与脱色率达到46.17%和50.61%,优于亚硫酸法,这可由清汁、糖浆及白砂糖紫外全波扫描图证实。     

一种甘蔗混合汁无硫二步澄清工艺优化研究

以石灰、磷酸、单宁和Ca(HCO_3)_2作为澄清剂对甘蔗混合汁进行二步澄清处理,通过单因素试验和正交试验确定第二步澄清最佳工艺参数。二步澄清最适工艺参数反应pH 8.6,单宁用量为150 mg/L,1.66%的Ca(HCO_3)_2溶液用量为10 mL/100 mL蔗汁。无硫二步澄清工艺的澄清效果与亚硫酸法的没有显著性差异(p0.05),满足了白砂糖生产的工艺要求,可解决了我国白砂糖含SO_2问题,对提高了我国食糖食用安全性具有积极意义。     

浅谈糖浆二次硫熏

本文论述了亚硫酸在糖浆中的反应机理，指出糖浆二次硫熏的必要性和重要性，以及良好的澄清和适量硫熏是提高白砂糖产品质量的关键工艺之一。     

甘蔗糖厂硫熏过程氧气对白砂糖色值的影响研究

从产品质量角度探讨亚硫酸法糖厂在硫气管路泄漏前后产品色值的情况,在线跟踪生产过程中清汁、糖浆、白砂糖的色值变化情况,结合生产过程中糖品主要色素成分的变化进行分析,确定造成硫气管路泄漏前后白砂糖色值超标的主要原因,并提出在生产过程中预防和减少物料与氧气接触的措施。     

甘蔗糖厂多次元精准配比低温新型燃硫炉系统的开发与应用

本研究开发并介绍了新型低温燃硫炉系统,分析了该系统在亚硫酸法甘蔗糖厂实际生产中的应用效果。结果表明：新型燃硫炉系统能够显著提升清混汁纯度差,澄清效果明显改善。同时,白砂糖质量明显提升,其中色值降低10%以上,AA级白砂糖产率提升20%左右。该应用对于提高亚硫酸法甘蔗糖厂生产澄清效果,提升产品质量,降低生产成本,促进生产向自动化、智能化发展具有重要的意义。     

3种澄清工艺白砂糖主要致色成分的差异研究

研究亚硫酸法、碳酸法、二步法3种经典澄清方法白砂糖样品的致色成分的差异,系统探讨白砂糖致色非糖分与色值的关系有重要的现实意义。通过测定榨季不同工艺不同色值段典型白砂糖中酚类物、铁、氨基氮含量,分析这些主要致色成分在砂糖中的分布规律。结果为:不同工艺不同糖厂白砂糖色值(IU)整体上随着酚类物、铁、氨基氮含量的增加而呈升高趋势;不同工艺同一色值段白砂糖致色成分含量不同,同一工艺同一色值段不同时期白砂糖样品的致色成分含量各有差异;亚硫酸法、碳酸法、二步法白砂糖酚类物含量依次为13.71~17.26、11.73~16.38、5.60~10.55 mg/kg,铁含量范围依次为2.17~4.08、1.54~2.18、0.39~1.23 mg/kg,氨基氮含量范围依次为17.17~33.68、14.33~20.75、0.19~2.30 mg/kg。     

活性碳改善亚法工艺提升白砂糖质量试验

在亚硫酸法糖厂澄清工段混合清汁的基础上 ,采用活性碳吸附剂技术改善清汁质量生产优级白砂糖 (饮料糖 ) ,与前期生产相比较。结果表明 ,采用该工艺技术后 ,能显著提升清汁、精糖浆及白砂糖质量 ,当中间各项控制指标稳定后 ,能直接生产出符合饮料糖标准的优质白砂糖 ,特别能大幅度降低白砂糖的混浊度、SO2 含量、色值等 ,解决困扰亚法糖厂多年的积疾。     

提高白砂糖质量技术改造实践探索

介绍亚硫酸法糖厂提高白砂糖质量的技术改造实践。运行表明,通过技改后,能使赤砂回溶糖浆与粗糖浆均匀按比例混合,同时能去除赤砂回溶糖浆的部分杂质和绝大部分色素,满足制糖工艺要求,提高了白砂糖质量,降低生产成本和储存白砂糖的基础色值,延长储存时间,减少库存增色,降低客户投诉产品风险,保持良好的品牌效应。     

糖浆硫熏对白砂糖色值的影响

用数理统计方法,找出了糖浆的色值和酸值与白砂糖色值的关系。指出了糖浆硫熏不但不能降低白砂糖色值,反而使白砂糖色值略有升高。     

亚硫酸法糖厂清汁上浮清净技术的研究与开发

本文介绍了清汁上浮技术在亚硫酸法糖厂澄清工艺的应用研究，通过生产试验证明，该清汁上浮清净技术有一定的优越性和先进性，达到提高清汁质量、成本低廉、降低糖粉转化，获得低色值、低浊度和低含硫的糖浆的目的。     

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.     

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