双菌株联合固态发酵冷榨核桃粕提高产品纳豆激酶活性的研究

为提高纳豆芽孢杆菌单菌发酵品的纳豆激酶(nattokinase,NK)活性并减少产品的不良氨味,采用戴尔凯氏有孢圆酵母、植物乳杆菌分别与纳豆芽孢杆菌联合固态发酵核桃粕。结果表明:纳豆芽孢杆菌与戴尔凯氏有孢圆酵母在接种量3%、菌种配比2∶1、发酵温度34℃、发酵时间60 h的条件下得到的核桃粕发酵品NK活性达2040.82 U/g,提高了70.42%,挥发性盐基氮含量为64.18 mg/100 g,降低了84.37%;纳豆芽孢杆菌与植物乳杆菌在接种量9%、菌种配比1.5∶1、发酵温度42℃、发酵时间60 h的条件下得到的发酵品NK活性为1966.02 U/g,提高了64.18%,挥发性盐基氮含量为62.68 mg/100 g,降低了84.74%。混合菌种发酵品的氨味显著减少,改善了传统发酵品的风味。      

木薯原料生产酒精的关键技术

木薯原料生产酒精的关键技术 :(1)适当减小引风机风量 ,避免粉尘飞扬 ,减少淀粉损失 ;(2)预煮拌料水温控制在55±5℃ ,蒸煮温度135±5℃ ,糊化时间80min以上 ,糖化温度58～60℃ ;(3)用酶量140～150u/g料 ,糖化时间40～50min;(4)干酵母采用小酒母和大酒母两级培养 ,芽生率稳定在18 %～25 % ,细胞数0.9～1.5亿/ml;(5)发酵顶温35～37℃ ,48～56h发酵结束。成品酒精质量达到国标普级标准 ,原料出酒率达36.02 %。     

余甘果酒酿制工艺的研究

研究并制定了余甘果酒酿制的工艺路线与技术参数,结果表明:原料果在2.5%～4.0%的NaOH溶液(温度70～80℃)中去皮20～40s,再用100℃蒸汽处理1.5～2min,浆体中果胶酶和NaHSO3分别按0.1%(浆体重)、120～150mgSO2/L(浆体重)进行添加,采用一次加糖法将浆液糖度调至20%～25%,pH值控制在3.5～4.0(酸度为1.0～1.10g/100ml)的条件下主发酵10～12d(发酵温度15～20℃),后发酵3～4d并陈酿2～3个月,采用明胶澄清法澄清酒体并过滤,最后在65～70℃、杀菌时间15min条件下进行巴氏杀菌,所酿制出的余甘果酒品质最好。     

海洋红酵母培养条件的研究

通过碳源、氮源及主要营养与环境条件等对海洋红酵母产菌量的影响试验,以及蔗糖、蛋白胨、酵母膏三因素三水平的正交试验,获得了海洋红酵母的最佳发酵条件:蔗糖1.5%,蛋白胨1.0%,酵母膏0.5%,磷酸二氢钾0.15%,硫酸镁0.01%,氯化钠1.0%,初始pH5.0,接种量8%,500mL三角瓶中培养基装量为80mL,发酵温度为28℃,摇床200r/min。在此优化的培养条件下,海洋红酵母的产菌量可达9.7亿个/mL,比优化前发酵培养基产菌量(5.6亿个/mL)提高了73.2%,比单因素试验结果(8.1亿个/mL)提高了19.8%。     

液态深层发酵酿造枣醋工艺研究

以金丝小枣为原料,采用液体深层发酵方式酿造枣醋,通过研究酿造过程中酒精发酵阶段酒精度和还原糖的变化,醋酸发酵阶段总酸和酒精度的变化,确定了液态深层发酵酿造枣醋的工艺.结果表明,酒精发酵阶段枣浆的初始糖度13.8%,酵母菌接种量0.03%,发酵温度25°C～30°C,发酵3.5 d结束,酒精度为8.4%(v/v).醋酸发酵阶段的初始酒精度为6.3%(v/v),初始酸度为1.5g/100mL(以醋酸计),醋酸菌接种量10%(v/v),发酵温度31℃,通风量600l/h-10001/h,发酵44h结束,最终酸度达到7.82g/100mL.所酿制的枣醋枣香浓郁,营养丰富.     

芦荟糯米保健醋的研制

以芦荟原汁、糯米、酿酒干酵母、醋酸菌为原料,通过单因素实验和正交试验,探索了芦荟糯米醋的发酵工艺。通过正交试验确定了最佳组合为酵母活化液接种量为1.0%(V/V)、糯米与芦荟汁混合比为3∶2(g/mL),加水量为芦荟糯米混合量的1.5倍,发酵温度为28℃。芦荟糯米醋的最佳醋酸发酵条件为发酵温度30℃、酒精度10%(V/V)、接种量4%(V/V)、发酵时间96 h,可获得6.48 g/100 mL芦荟糯米保健醋。酿制的芦荟糯米醋香味独特,品位纯正。     

类芽孢杆菌产胆固醇氧化酶的最适产酶条件研究

对诱变过的产胆固醇氧化酶的类芽孢杆菌(Paenibacillus sp.X534)在最适培养基进行了发酵条件的优化,确定其最适发酵条件为起始pH值为8,接种量8%,装液量16%,摇瓶转速180r/min,培养温度34℃,发酵时间50h。优化之后胆固醇氧化酶活达到约580U/L,比优化前提高了约1.5倍。     

发酵温度对高盐稀态酱油原油品质的影响

研究了不同发酵温度(35、25℃、自然)对高盐稀态酱油原油品质的影响。结果表明,高盐稀态酱油在25℃下发酵品质最好,发酵60d后总氮含量为1.23g/100mL,氨基酸态氮为0.74g/100mL,总酸和还原糖分别为2.03、3.37g/100mL,pH为4.60。25℃下发酵酱油的氨态氮含量与35℃和自然发酵的酱油相比,分别高出了11.68%和8.55%,而且25℃发酵的酱油其游离氨基酸总量也最高,为55.67mg/mL,其中必需氨基酸占43.97%,鲜味氨基酸占29.20%,甜味氨基酸占22.06%,均高于35℃和自然发酵的酱油。25℃发酵酱油的赖氨酸含量为3.91mg/mL,分别比35℃和自然发酵酱油高出16.37%和15.69%。     

梅香黄鱼低盐腌制-发酵过程中的品质变化规律研究

为研究梅香黄鱼在低盐腌制-发酵过程中的品质变化规律,考察了不同用盐量(5%、10%、15%)、温度(10℃、25℃、32℃)和腌制时间(0～5d)对主要理化指标和感官特性的影响。理化分析结果表明:用盐量对含盐率、含水率、质量变化率、汁液流失率的影响比温度大。用盐量越大或温度越低,AAN、TVBN含量的增加速率均越慢。用盐量越大,pH值下降程度越大,回升时间越迟。温度越高,最终pH值越高。感官评定结果表明:32℃下用盐量为10%腌制3d的样品和用盐量为15%腌制4d的样品均较好。对于用盐量为10%时,25℃腌制的样品感官品质比32℃好;对于用盐量为15%时,25℃和32℃的腌制效果相似。15%腌制4d的样品经过脱盐后,咸味得以改善,而梅香风味损失不多,整体可接受性更好。相关性分析结果表明,主要理化指标与感官指标之间存在显著相关性,因此可以作为品质指标控制如下:含盐率7g/100g(WB),含水率在54～60g/100g(WB),AAN0.2g/100g(WB),TVBN96mg/100g(WB)。     

发酵温度对高盐稀态酱油原油品质的影响

研究了不同发酵温度(35、25℃、自然)对高盐稀态酱油原油品质的影响。结果表明,高盐稀态酱油在25℃下发酵品质最好,发酵60d后总氮含量为1.23g/100mL,氨基酸态氮为0.74g/100mL,总酸和还原糖分别为2.03、3.37g/100mL,pH为4.60。25℃下发酵酱油的氨态氮含量与35℃和自然发酵的酱油相比,分别高出了11.68%和8.55%,而且25℃发酵的酱油其游离氨基酸总量也最高,为55.67mg/mL,其中必需氨基酸占43.97%,鲜味氨基酸占29.20%,甜味氨基酸占22.06%,均高于35℃和自然发酵的酱油。25℃发酵酱油的赖氨酸含量为3.91mg/mL,分别比35℃和自然发酵酱油高出16.37%和15.69%。      

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press