消臭粘胶纤维的制备与性能研究

将具有消臭功能的海藻糖粉末和蛋白石微粉水化液与粘胶纺丝液共混,选取最佳添加形式与共混比例,根据粘胶纤维生产工艺制备消臭粘胶纤维,并测试其基本性能与消臭性能。结果表明,与普通粘胶纤维相比,消臭粘胶纤维断裂强度、断裂伸长率均有所下降,回潮率稍有降低,比电阻减小,消臭性能优异。     

海藻糖对虾蛄磷酸化肌原纤维蛋白功能特性的影响

将适量的海藻糖加入虾蛄磷酸化肌原纤维蛋白（myofibrillar protein,MP）中,研究其添加量对蛋白质乳化、理化及凝胶特性的影响。结果表明：当海藻糖添加量为0.4 mg/mL时,虾蛄磷酸化MP的乳化活性达到最大,乳化稳定性则随海藻糖添加量的增加而逐渐增大,并在海藻糖添加量为1.0 mg/mL时达到最大;海藻糖添加量逐渐增大时,虾蛄磷酸化MP的表面疏水性呈现先增加后降低的趋势,并在添加量为0.2 mg/mL时达到最大;浊度先增加后逐渐降低,在添加量为0.4 mg/mL时达到最大;MP的起泡性（foaming characteristics,FC）和泡沫稳定性（foam stability,FS）随着海藻糖添加量的增加均呈现先增加后降低的趋势,海藻糖添加量为0.4 mg/mL时,FC达到最大;随着海藻糖添加量的增大,磷酸化MP凝胶的保水性呈现先增加后降低的趋势,并在海藻糖添加量为0.4 mg/mL时达到最高,凝胶硬度也呈现先增加后降低的趋势,弹性呈现逐渐增加的趋势,凝胶白度呈现先增加后降低的趋势。差示扫描量热仪扫描曲线反映出添加适量的海藻糖有利于MP结构的稳定。     

海藻糖对水饺皮保水性及质构特性的改良

为解决实际生产中水饺皮易失水干裂,导致水饺皮捏合性差等问题,通过加入不同添加量海藻糖(0、1.0%、2.0%、3.0%、5.0%)对水饺皮品质进行优化。以面粉湿面筋含量、水饺皮失水率、煮制吸水率及质构特性为评价指标,确定海藻糖的最适添加量。结果表明:海藻糖添加量为2.0%时,面粉湿面筋含量最大,较空白组增加了15.49%。海藻糖的加入可以降低水饺皮的失水率,当添加量≥1.0%时,失水率较空白组显著降低,当添加量达到5.0%时,失水率最低为7.46%;海藻糖的添加可以增强水饺皮的煮制吸水率,当海藻糖的添加量为1.0%时,水饺皮的吸水率最大为54.41%,较空白组增加了13.85%。海藻糖的加入使水饺皮面团表现出良好的拉伸特性,当添加量为1.0%时,抗延伸阻力最大为83.73 g。海藻糖的添加可改善生水饺皮及熟水饺皮的TPA特性,与空白组相比,海藻糖的添加量≥3.0%时,生水饺皮的粘着性显著增加,使生水饺皮在包制过程中更易捏合,2.0%海藻糖使熟水饺皮硬度增加了14.60%,咀嚼性增加了11.66%。综合表明,适量海藻糖的添加能够改善水饺皮的品质,可考虑将其作为改良剂应用于水饺皮的生产中,且海藻糖的最适添加量为2.0%。     

蔗糖和海藻糖对糯米淀粉凝胶冻融稳定性的影响

为提高糯米淀粉凝胶冻融稳定性,研究了蔗糖和海藻糖对淀粉凝胶析水率、质构特性、热特性及微观结构的影响。结果表明,经过5次冻融处理,蔗糖和海藻糖均能显著降低淀粉凝胶析水率,且添加6%蔗糖与添加4%海藻糖对凝胶析水率的影响相同。添加2种糖后,凝胶弹性增加,硬度先增大后减小。差示扫描量热仪测定显示添加2种糖的淀粉凝胶熔融焓/糊化焓均显著降低,表明淀粉老化受抑制,且抑制能力为海藻糖大于蔗糖。利用扫描电镜观察凝胶微观结构发现,添加海藻糖的淀粉凝胶表面光滑平整,凹洞较小,基质较紧密。与蔗糖相比,海藻糖更能提高糯米淀粉凝胶冻融稳定性。     

海藻糖添加量对糯米粉理化性质影响研究

研究海藻糖添加量对糯米粉糊化特性、冻融稳定性、高温持水能力等理化性质的影响。结果表明,随海藻糖添加量的增加,糯米粉糊化温度升高,峰值黏度、谷值黏度、最终黏度先增大后减小,在添加量为1.0%时达到最大值,热稳定性先增强后减弱,在海藻糖添加量为1.5%时最强,凝胶性逐渐降低;透明度先减小后增大,最终趋于稳定,在海藻糖添加量为1.0%时呈最小值,且常温下粉糊的透明度大于4℃下粉糊的透明度;冻融稳定性逐渐增强;沉降性逐渐减弱;高温持水能力逐渐增强,后趋于稳定。     

海藻糖对罗非鱼糜及蛋白抗冻作用的研究

以罗非鱼为原料,提取肌原纤维蛋白,添加10%海藻糖。在不同的冷冻时间下对其蛋白盐溶性,ATPase活性及巯基含量为指标,与未添加海藻糖对比研究肌原纤维蛋白的变性程度。制作罗非鱼糜,添加10%海藻糖作为对比,与蛋白变性过程同步,研究鱼糜的凝胶强度、保水性、弹性、咀嚼性等指标。结果表明,随着冻藏时间的延长,鱼糜蛋白盐溶性ATPase活性及巯基含量均呈下降趋势,鱼糜的保水性、弹性凝胶强度等也同步下降。而添加海藻糖对该趋势有抑制作用。     

外源海藻糖对啤酒酵母在热胁迫下的保护作用

为探究外源海藻糖对啤酒酵母在热胁迫下的保护作用,作者在3个热胁迫条件下检测外源海藻糖对啤酒酵母活力及活性的影响,并通过分析转录组数据对热胁迫下外源海藻糖对啤酒酵母的保护作用机理进行初步分析。结果表明,外源海藻糖可以提升啤酒酵母的耐热性,但具有一定限度,温度的升高和胁迫时间的延长导致不同浓度海藻糖的作用差别减小。另外,添加海藻糖可以增加酵母胞内海藻糖质量分数,添加海藻糖对啤酒酵母转录水平上的影响主要体现在核糖体的合成和相关功能上。结合本研究推测,外源海藻糖对啤酒酵母在热胁迫下的保护作用是通过增加胞内海藻糖质量分数实现的,上升的胞内海藻糖质量分数促进了核糖体合成及相关代谢,使核糖体功能增强,进而实现对啤酒酵母耐热性的增强。     

杏鲍菇中海藻糖和多糖含量分析

采用高效液相色谱法测定了用不同培养基栽培的杏鲍菇中海藻糖的含量,结果表明杏鲍菇具有高于香菇的海藻糖含量,采用含有机质丰富的材料栽培杏鲍菇可提高海藻糖和多糖的含量,在基本培养基中添加15%大麦虫沙栽培时,杏鲍菇鲜品的海藻糖含量可达2.03g/100g,提高了54.9%,添加20%的沼渣时,多糖含量可提高约一倍。     

海藻糖抑制炒米饼氧化的研究

研究了海藻糖对炒米饼的油脂氧化抑制效果,以酸价(AV)、过氧化值(POV)和总挥发醛为主要评价指标,通过加速氧化方法(45℃下氧化),比较海藻糖、葡萄糖、蔗糖和TBHQ等四种物质抑制炒米饼氧化作用。研究结果表明,添加海藻糖、葡萄糖、蔗糖和TBHQ的炒米饼,在保藏初期的AV和POV差异不大,但就挥发醛的量来看,添加海藻糖的炒米饼挥发醛特别少。随着时间的延长,添加蔗糖和葡萄糖的炒米饼AV、POV和挥发醛量都在明显的增加,而添加TBHQ和海藻糖的炒米饼的AV、POV和挥发醛量基本不变。保存30d时,添加TBHQ炒米饼的AV、POV和总挥发醛量分别为3.12mgKOH/g油、8.76meq/kg和4.8μg/g,而添加海藻糖炒米饼的AV、POV和总挥发醛量分别为3.27mgKOH/g油、11.19meq/kg和1.2μg/g。综合三个指标的变化情况,海藻糖可以有效地减少炒米饼中总挥发醛量的生成,抑制炒米饼中油脂的氧化。     

外源相容性溶质对S酵母耐盐性及酱油风味形成的研究

研究外源相容性溶质对S酵母(Zygosaccharomyces rouxii)耐盐性的影响,并探讨在高盐稀态酿造工艺中添加海藻糖对酱油风味的影响.结果表明,在酵母培养基中添加0.005mol/L海藻糖、甜菜碱和山梨醇,均可以显著改善S酵母在高盐培养基中的生长情况,缩短渗透胁迫条件下S酵母的延滞期,增加生物量,其中海藻糖的渗透保护效果最佳;添加海藻糖可使酱油的主体香味物质HEMF(4-羟基-2-乙基-5-甲基-3-呋喃酮)和乙酸乙酯的含量显著增加,同时促进S酵母合成酱油中典型风味物质4-EG (4-乙基愈创木酚).在酱油高盐稀态酿造中添加相容性溶质,如海藻糖,可有效改善酱油的风味和品质.     

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.     

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.     

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.     

Food-borne Listeria monocytogenes risk assessment

Listeria monocytogenes is ubiquitous in the environment and in food processing plants. Consequently, foods are frequently contaminated. However, the occurrence rate of listeriosis is only about five cases per million people per year. Listeriosis primarily strikes immunocompromised individuals, pregnant women and the elderly with a fatality rate of 20-25%. The FDA is in the process of finishing a risk assessment that is being conducted as an initial step in reviewing its approach to maximizing the public protection from foodborne L. monocytogenes . The risk assessment evaluated the presence and quantitative levels of L. monocytogenes in 21 groups of ready-to-eat foods. The potential growth of L. monocytogenes between retail point-of-sale, where contamination data originated, and consumption was modelled. The frequency and amount of consumption of these foods completed the data for the exposure assessment. For the hazard characterization or dose response part of the risk assessment, data from animal studies, virulence assays and epidemiological investigations were used to estimate the likelihood of illness for different human groups from consuming different numbers of L. monocytogenes . This risk assessment is a virtual review of current scientific knowledge. Quantitative modelling provides greater insight than a qualitative review and also indicates the uncertainty about our knowledge. The risk assessment does not attempt to define an acceptable or tolerable level of L. monocytogenes consumption or propose changes in regulations. These decisions are the responsibility of risk managers who consider additional factors such as food preferences, technical feasibility and societal values when evaluating regulatory policies.     

Nationaler Rückstandskontrollplan – Stärkung des Verbraucherschutzes durch gezielte Kontrollen bei tierischen Lebensmitteln

Zusammenfassung. Der Nationale Rückstandskontrollplan ist ein seit 1989 von Bund und L?ndern durchgeführtes Programm zur überwachung von Lebensmitteln tierischer Herkunft in verschiedenen Produktionsstufen auf Rückst?nde von gesundheitlich unerwünschten Stoffen. Koordinierende Stelle ist seit dem 01. 11. 2002 das Bundesamt für Verbraucherschutz und Lebensmittelsicherheit. Das Programm wird in der Europ?ischen Union nach einheitlich festgelegten Ma?st?ben durchgeführt. In Deutschland werden j?hrlich ca. 45.000 Tiere oder tierische Erzeugnisse auf verschiedene Stoffe und Stoffgruppen analysiert. Der Plan enth?lt für jedes Bundesland konkrete Vorgaben über die Anzahl der zu testenden Tiere bzw. tierischen Erzeugnisse, die relevanten Stoffe, die anzuwendende Methodik und die Probenahme. Die Probenahme erfolgt zielorientiert. Der Rückstandskontrollplan ist nicht auf die Erzielung statistisch repr?sentativer Daten ausgerichtet. Dargestellt werden Ziele, Organisation und Durchführung des Planes sowie einige Ergebnisse aus den letzten zehn Jahren.      

Innovation in Linen Manufacture

This monograph traces the various means by which flax fibre is transformed into linen yarns and fabrics. The principal innovations and developments of the past fifty years are identified. An extensive range of relevant literature is reviewed. Details are given of how the fibre is extracted from the stem of the flax plant and of the stages of yarn and fabric production. An explanation is given of how yarns are produced from short fibres (known as tow) using carding, drafting and dry spinning, and from long fibres (known as line) using hackling, drafting, doubling, roving and wet spinning in warm water. Further areas covered include yarn winding, linen weaving, dyeing and finishing. New applications for flax fibre, beyond traditional uses in apparel or furnishing fabrics, are also identified.     

STANDARD SIZING AND FIT TESTING APPLIED TO WOMEN'S HOSIERY

The monograph deals with a critical review of the recent research work and development on ramie, a long vegetable bast fibre. The review is divided into two parts. Part I discusses the progress of recent work on ramie, chemical components like fibre degumming, its effects on fibre composition, chemical constituents, i.e. hemicellulose, cellulose, non-cellulosic and mineral matters. Besides various chemical properties of native and modified fibres such as accessibility, infrared, cellulose I–V, DP, grafting, cross linking and resin finishing and dyeing etc. are dealt with.     

Biological activities of oligoketide pigments of Monascus purpureus

Rubropunctatin (1) , monascorubrin (2) , monascin (3) and ankaflavin (4) were purified from the mycelium of Monascus purpureus by flash chromatography on silica gel or reversed phase. Their embryotoxicity towards chicken embryos decreased in the order 2> 1> 3> 4 . The lower homologues 1 and 3 exhibited teratogenic effects on these organisms. Significant antibiotic activities against Bacillus subtilis and Candida pseudotropicalis were found with compounds 1 and 2 . Immunosuppressive activity on mouse T-splenocytes was most pronounced with compounds 3 and 4 . None of the compounds showed significant cytotoxic activity towards rat hepatocytes in vitro . Incubation of resting cells of M. purpureus with glycine afforded the dark-red compounds 5 and 6 where the pyran moiety of 1 and 2 changed into the N-substituted dihydropyridine moiety by replacement of the O-atom by the amino group of glycine. Compounds 5 and 6 were less biologically active than the major pigments 1 - 4 .     

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.     

Die e-ventus Technologie – eine Innovation zur nachhaltigen Reduktion von Pflanzenschutzmitteln mit Empfehlung für Bio-Saatgut

Zusammenfassung:  Der intensive Pflanzenbau erfordert wirksame Pflanzenschutzma?nahmen. Eine der wirksamsten Ma?nahmen ist die Behandlung des Saatgutes gegen Pathogene. Sie erfolgt bisher fast ausschlie?lich durch chemische Beizmittel (Pestizide), die Anwender und Umwelt gef?hrden k?nnen. Neue Gesetze und Richtlinien in Deutschland und der Europ?ischen Union fordern die nachhaltige Einschr?nkung der Anwendung chemischer Pflanzenschutzmittel und den Ersatz durch neue, alternative Verfahren und Methoden. Als bereits praxisreifes Verfahren wird die e-ventus Technologie beschrieben. Neue Ergebnisse aus der Forschung, langj?hrige Feldversuche und Produktionserfahrungen best?tigen die Eignung dieser Technologie für den breiten Einsatz in der Landwirtschaft. Neben dem konventionellen Landbau wird die Eignung und Zulassung auch für den Bio-Landbau aufgezeigt. Eingegangen: 15. Januar 2009; angenommen: 10. Februar 2009