造纸法再造烟叶生产过程中氯含量的变化

分析了造纸法再造烟叶生产过程中氯含量的变化。结果表明:(1)提取液的氯含量与提取率无明显的相关性,而与梗、叶原料的氯含量相关;(2)浓缩、制浆抄造和干燥工序对产品氯含量的影响可以忽略不计;(3)涂布率和涂布液氯含量是影响再造烟叶产品中氯含量的主要因素,根据涂布率和涂布液中氯含量乘积可预测再造烟叶产品氯含量;(4)要控制成品氯含量,应控制涂布率和梗叶膏比例,并注意烟梗原料的氯含量。     

阴离子交换树脂脱除烟梗提取液中的氯化物和硝酸盐

为有效降低造纸法再造烟叶中氯化物和硝酸盐的含量,提高原料的综合利用效率,筛选了12种不同的阴离子交换树脂,考察了温度、时间、pH、浓度、树脂加入比例等条件对烟梗提取液中氯离子(Cl-)和硝酸根离子(NO3-)脱除效果的影响,并研究了优选树脂的回收及循环利用情况.结果表明:①D202大孔树脂的脱氯、脱硝效果最佳;②向固含量为8％的烟梗提取液中加入D202树脂,烟梗提取液与树脂质量比为0.8～1.0,40～45℃下处理5～7 min,可使烟梗提取液中C1和NO3-离子的含量分别降低60％和95％以上,且施加该处理后的烟梗提取液对再造烟叶产品的感官品质无不利影响;③D202树脂循环使用10次后,其脱氯、脱硝能力仍基本保持不变.     

电渗析对烟梗提取液中主要盐类物质的影响

为明确电渗析对烟梗提取液中主要盐类物质的影响,考察了电渗析对烟梗提取液4种无机酸盐(氯化物、硝酸盐、硫酸盐和磷酸盐)、3种金属盐(钾盐、镁盐和钙盐)及3种有机酸盐(苹果酸盐、草酸盐和柠檬酸盐)的脱除效果。结果表明:电渗析对不同的盐类物质脱除效果有差异,氯化物、硝酸盐和钾盐脱除较快。无机酸盐、金属盐和有机酸盐的脱除速率大小顺序分别为:氯化物 >硝酸盐 >硫酸盐 >磷酸盐,钾盐 >镁盐 >钙盐,苹果酸盐 >草酸盐 >柠檬酸盐。利用电渗析在调控烟梗提取液中氯含量的同时,也可以降低其硝酸盐含量,进而实现对再造烟叶产品氯和硝酸盐指标的调控。      

天然海泡石纤维在造纸法再造烟叶中的应用

为了深入分析天然海泡石纤维在部分替代再造烟叶烟梗纤维和外加本色剑麻纤维上的可行性,研究了本色剑麻纤维以及烟梗纤维的添加比例对再造烟叶感官特性的影响,并采用热重分析、纤维形态分析、纸张物理性能分析、感官评价等方法,研究了天然海泡石纤维的热解性质、纤维形态,以及替代烟梗纤维和本色剑麻纤维时的成纸物理性能及产品感官特性。结果表明:(1)天然海泡石纤维具备较好的化学惰性和纤维强度,其加权平均长度为593μm,长宽比为27.3,纤维长度分布与烟梗较为接近,具备一定的造纸价值,适于再造烟叶的生产;(2)本色剑麻纤维的添加对再造烟叶的杂气以及余味指标影响最为显著;烟梗纤维的添加则对灼烧感、刺激性、杂气有明显影响;(3)天然海泡石可部分替代本色剑麻纤维和烟梗纤维,替代比例分别达到30%和50%,所制备的再造烟叶与普通再造烟叶产品相比具有明显的感官质量优势。     

造纸法再造烟叶生产过程中梗膏提质酶技术的应用研究

造纸法再造烟叶产品中大分子物质的含量直接影响产品抽吸品质。用离子色谱结合紫外分光光度计等仪器分析烟梗提取液中纤维素、果胶、蛋白质、淀粉的含量,利用生物酶的专一性特点,对烟梗提取液进行酶解转化处理,通过分析各种单一酶对烟梗提取液中大分子物质的降解情况,确定单一品种生物酶用量,在此基础上,对生物酶进行复配,复配生物酶用于再造烟梗提取液中大分子物质的降解,结合现行生产工艺条件,对烟梗提取液中大分子物质的降解进行一定程度控制,为生产过程中烟梗提取液的提质奠定一定的理论依据。     

南平烟区烤烟氯化钾适宜用量的研究

为了确定南平烟区适宜的氯化钾用量,在南平烟科所试验基地和光泽县进行了不同氯化钾用量的大田试验.结果表明,不同氯化钾用量对烟叶各生育期几乎没有影响;各农艺性状、经济性状和感官质量随氯化钾用量均呈"抛物线"变化,感官质量主要表现在香气量上的变化,烟叶中氯离子含量随土壤水溶性氯含量和氯化钾用量的增加而增加,烟叶中的钾氯比主要受氯离子含量影响,土壤水溶性氯含量和施氯量对烟叶氯含量的影响和互作效应均达到极显著,施用氯化钾可以降低生产和生态成本,生产上建议南平烟区采用45 kg/hm2氯化钾用量较为适宜.     

膜技术提高造纸法再造烟叶的感官品质

为提高造纸法再造烟叶的感官品质,采用M50(50 nm)微滤膜、GU超滤膜1(标称截留分子量50000Da)和GM超滤膜2(标称截留分子量100000 Da)对烟梗、烟末萃取液进行了过滤处理,滤液再返加到再造烟叶中,并进行了评吸.结果表明:与处理前相比,①处理烟梗、烟末萃取液中的总氮分别下降62.5%和67.8%,果胶物质基本完全去除;②处理烟梗和烟末萃取液返加的再造烟叶的感官品质均有所提高,且微滤膜 超滤膜1处理的效果最好.膜分离技术可作为提高造纸法再造烟叶感官品质的一种可行的方法.     

应用高压美拉德反应改性烟梗提取液

为提高美拉德反应改性烟梗提取液的改性效率,在常压改性反应的基础上建立一种全新的应用高压反应釜在惰性高压的条件下改性烟梗提取液的方法。该方法在高压反应釜中加入烟梗提取液、一定比例的葡萄糖、脯氨酸和1, 2-丙二醇,在高温高压条件下反应以改善烟梗提取液的化学组成。结果表明,相较于常压改性反应,经过高压改性处理的烟梗提取液能产生更多的挥发性产物,能更有效地改善烟梗提取液的化学组成,改善再造烟叶的感官品质,降低木质气、杂气和刺激性。     

甘油碱法脱除烟梗中的木质素

  目的  应用甘油碱法工艺对烟梗进行处理,制备低木质素烟梗薄片。  方法  以木质素脱除率和浆得率为衡量指标,对甘油碱法制浆工艺条件进行了优化,并比较了不同预处理工艺对再造烟叶烟气评吸质量的影响。  结果  （1）甘油碱法制浆最佳工艺条件为,氢氧化钾用量45%、蒸煮温度为200℃、蒸煮液固比为11∶1、蒸煮时间为0.5h,此时烟梗中的木质素含量为5.06%,木质素脱除率为43.01%,浆得率为37.12%。（2）甘油碱法的木质素脱除率和木质气降低效果虽然稍逊色于氧碱法,但其对烟气质量提升的综合效果明显优于氧碱法和乙酸法。（3）采用甘油碱法再造烟叶制备的项目卷烟,其感官质量优于常规卷烟。  结论  采用甘油碱法工艺制备的烟草薄片,木质素含量低,应用于卷烟中可提升烟气品质。      

不同溶剂预处理对烟梗打浆抄造及评吸性能的影响

以热水抽提、乙醇水溶液和碱性离子液体1,3-二甲基咪唑磷酸二甲酯([MMIM]DMP)为溶剂,对烟梗进行预处理,研究不同溶剂对烟梗中木素的去除效果及溶剂处理后打浆抄造性能和再造烟叶评吸性能的变化。结果表明,碱性离子液体对烟梗中木素的去除率最高,约为热水抽提的5倍,远大于乙醇水溶液对木素的去除率;相对于热水抽提和乙醇水溶液处理,经碱性离子液体处理后的烟梗打浆后纤维的分散程度较好,打浆性能明显提升,抗张强度提高,松厚度和透气度也得到了进一步改善;碱性离子液体脱除烟梗中大量木素后,使各烟气指标的含量和感官质量指标的分数得到了优化,评吸性能明显改善,从而提高了烟草废弃物的利用率,提升了再造烟叶产品品质。     

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