铵碱法预处理烟梗纤维提高造纸法烟草薄片品质的研究

采用铵碱法[CO(NH2)2和KOH]对烟梗纤维进行预处理,以改善烟梗纤维的物理性能,提高造纸法烟草薄片的感官质量。结果表明,在CO(NH2)2用量1.0%、KOH用量1.0%、处理温度45℃和处理时间3.0 h条件下,烟梗基片的抗张指数、松厚度和柔软度分别为32.8 N·m/g、2.89cm3/g和37.3 mN,与未预处理烟梗基片相比分别提高了9.33%、16.5%和27.4%;卷烟感官评吸表明,与采用普通造纸法烟草薄片卷制的卷烟相比,经上述铵碱预处理后的造纸法烟草薄片卷制的卷烟,感官评吸得分最高,比普通卷烟高1.9分。     

细小纤维对造纸法烟草薄片基片物理性能的影响

利用漂白硫酸盐针叶木浆制备不同长度的细小纤维,考察其对烟草薄片基片物理性能(抗张强度、松厚度、柔软性能、粗糙度和透气度)和浆料滤水性能的影响,并对细小纤维用量进行优化.实验结果表明,随着细小纤维平均长度的降低,基片的抗张强度提高,与此同时松厚度和柔软性能受到影响,浆料的滤水性能下降;木浆纤维用量15％、添加平均长度0.622mm的细小纤维可较好地改善基片的各项物理性能,其中细小纤维合适的用量为1.5％;与传统工艺(木浆纤维用量20％)相比,木浆纤维用量降低了25％左右,减少了卷烟木质杂气的产生量.     

浆料净化技术在烟草薄片生产中的应用研究

分析了现有造纸法烟草薄片流送系统存在的问题,研究了流送系统改造后对烟草薄片生产的影响。结果表明,改造后生产稳定性和产品质量得到不同程度的提升;烟草浆料经净化处理后,可有效减少大尺寸杂质,基片的匀度、抗张强度和手感柔软度均得到不同程度的提高,抗张强度、松厚度稳定性提高,基片掉毛掉粉量减少。     

烟梗颗粒加填对再造烟叶基片物理性能的影响

提高造纸法再造烟叶的松厚度可有效改善涂布液的吸收性和卷烟的填充值,对实现我国卷烟“减害降焦”具有重要意义。本研究将烟梗粉碎后获取的不同粒径的梗颗粒（d₁＞60目、80目＜d₂≤60目、120目＜d₃≤80目、200目＜d₄≤120目）作为填料添加到再造烟叶基片中,探究了梗颗粒粒径对基片物理性能的影响。结果表明,添加4种不同粒径的梗颗粒对基片松厚度和透气度均有改善作用。随着梗颗粒粒径的增加,基片的松厚度逐渐提高。与未添加梗颗粒的基片相比,添加d₁粒径的梗颗粒可使基片松厚度提高8.31%;基片的抗张指数随着梗颗粒粒径的降低有所增加。此外,d₁和d₂粒径的梗颗粒对基片柔软度也有一定的改善作用。     

纳米纤维素替代部分造纸法烟草基片中木浆纤维的研究

为了改善烟草基片的性能,研究了在造纸法烟草基片的抄造中用纳米纤维素替代部分木浆纤维对烟草基片性能的影响,优选出效果最佳的纳米纤维素,并得到优化的工艺条件。结果表明,阳离子型纳米纤丝纤维素(NFC)能有效改善烟草基片的性能;添加0.1%(相对绝干烟草浆料)的阳离子型NFC,能使烟草基片中的木浆含量由25%降低至16.7%(降幅为33.2%),并保持烟草基片的抗张指数和松厚度等性能基本相同。阳离子型NFC的加入降低了烟草基片中木浆纤维的含量,进而有效提升卷烟的吸食口感。     

中浓压力筛筛鼓缝宽对烟草基片浆料分布及其物理性能的影响

为了分析不同筛鼓缝宽对烟草基片浆料分布和其物理性能的影响,采用中浓压力筛对烟草基片浆料进行处理,观察烟草基片筛前浆料、筛后良浆和尾浆的纤维组分分布,并分别检测其基片松厚度、抗张指数等物理性能。结果表明,与筛前浆料相比,筛后良浆16目以下组分占比明显降低,200目以上组分占比明显增加,纤维分布更加集中、均匀;筛后浆料基片的柔软性能有较大改善,松厚度有所提高,但抗张指数、撕裂指数分别下降。与旧筛(0.55 mm缝宽)相比,增大压力筛筛缝宽度后,筛后良浆纤维组分并未出现明显变化,但筛后浆料基片松厚度相比筛前基片提高了4.55%,大于采用旧筛时基片松厚度的提高幅度1.33%。尾浆纤维组分主要集中在16目以下范围,占比可达50%。尾浆基片松厚度优于筛前和筛后基片,但伸长率和柔软性能较差,抗张指数及撕裂指数与筛后基片相近,但低于筛前基片。     

改善造纸法烟草基片松厚度的研究

研究了造纸法烟草基片生产过程中,烟梗浆与烟末浆比例、木浆和沉淀碳酸钙(PCC)用量对烟草基片松厚度和抗张强度的影响。结果表明,适宜的木浆添加比例约为20%;增加烟草浆中烟末浆的比例对基片的松厚度有利,但是对烟草基片的强度性能具有负面影响,烟草浆中适宜的烟末浆比例约为50%。     

加热卷烟烟芯材料及烟支的吸湿特性研究

为探讨加热卷烟吸湿特性,采用化学分析法、图像分析技术及感官质量评价,研究了利用稠浆法和造纸喷粉法制备的两种加热卷烟烟草薄片的面积、厚度及相应烟支圆周随环境相对湿度变化规律。结果表明,烟草薄片的面积、厚度及烟支圆周均随环境相对湿度增加而增加,且烟支圆周增加与烟草薄片厚度增加正相关。受烟草薄片制备工艺的影响,稠浆法烟草薄片面积和厚度增加幅度显著大于造纸喷粉法烟草薄片。其中,稠浆法烟草薄片面积增加主要归因于纵向长度增加,厚度增加归因于疏松部位吸水后体积润胀。烟草薄片含水率随环境相对湿度增加而增加,进而影响感官质量,体现在口腔灼热感随环境湿度增加而增加。当环境相对湿度在40%~50%之间时,烟草薄片和烟支的各指标稳定性较好,有利于烟草薄片及烟支的存储。     

打浆工艺对造纸法再造烟叶基片松厚度的影响

采用PFI磨对烟草浆进行打浆,分别研究了磨浆转数、磨齿间隙和打浆浓度对造纸法再造烟叶基片松厚度的影响,同时通过对不同打浆参数条件下得到的烟草浆纤维形态的对比,探讨了打浆工艺对造纸法再造烟叶基片松厚度的影响。结果表明,烟草浆打浆过程中,随着磨浆转数的减少,磨齿间隙的增加以及打浆浓度的提高,纤维数量下降、平均长度上升、粗度增加,与木浆、轻质碳酸钙混合抄造出的基片松厚度提高;在本实验打浆工艺范围内,磨浆转数和磨齿间隙对烟草浆纤维形态以及抄造出的基片松厚度的影响大于打浆浓度的影响;由于烟草浆纤维本身的特点,不同的打浆工艺对其帚化效果影响很小;适宜的PFI磨打浆工艺为:磨浆转数10000~15000转,磨齿间隙0~0.5 mm,打浆浓度10.0%~11.7%。     

造纸法烟草薄片打浆工艺和助留助滤剂的研究

首先对国内外烟草薄片成品的性能差异进行了分析比较,针对国内造纸法烟草薄片存在的质量问题,采用KRK磨浆机,进行烟草浆不同磨浆浓度条件下（4%、8%、18%、30%）的磨浆实验,并将由烟梗和碎烟制备的烟草浆与木浆配抄烟草基片,考察了磨浆浓度、添加不同助留助滤剂对烟草基片松厚度、干/湿抗张强度以及配抄浆料留着和滤水性的影响。结果表明：采用低浓（4%）磨浆、添加适量（0.6%左右）的壳聚糖抄造,所得烟草基片的综合质量较好,配抄浆料的留着和滤水性能好。     

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