复合酶水解牛肉的研究

研究了以牛肉为原料，选择复合蛋白酶(Protamex)和复合风味酶(Flavourzyme)分步水解牛肉蛋白。通过对影响牛肉水解因素的考察，得出Protamex酶的最适水解条件为：前处理加热温度90℃，加热时间10min，加酶量2％，反应温度55℃；，pH值6．0，固液比1：5，反应时间为6h，此条件下的水解度为12．57％。为了提高牛肉的水解度，采用双酶水解，其工艺条件为1先用Protamex水解6h，然后用Flavourzyme再水解6h，Flavourzyme的水解条件为加酶量6．0％，反应温度50℃，其它条件与Protamex相同，在此条件下水解度可达24.62％。     

双酶水解虾粉制备虾风味基料的研究

用Flavourzyme复合风味蛋白酶和Protamex复合蛋白酶同步水解虾粉制备虾风味基料,最佳酶解条件为:底物浓度为11.0%、Flavourzyme复合风味蛋白酶和Protamex复合蛋白酶的添加量均为0.8%、水解温度55 ℃,起始pH值6.5,酶水解时间3 h,水解度为23.6%;水解液经浓缩后即可得到虾味浓郁的风味基料.     

Protamex复合蛋白酶水解牛肉的研究

为优化牛肉酶水解条件，本试验采用响应面法对Protamex复合蛋白酶水解牛肉的条件进行研究。建立了水解度（DH）与pH值、反应温度、反应时间、固液比、酶与底物浓度比之间的数学模型；并获得最佳水解工艺条件：pH值6．4，温度54℃，水解时间6h，固液比1：5．2，酶与底物浓度比2％。     

Protamex复合蛋白酶水解大豆分离蛋白的研究

为优化大豆分离蛋白酶水解条件，本试验采用二次回归正交旋转组合设计方法对Protamex复合蛋白酶水解大豆分离蛋白的条件进行研究。建立了水解度(DH)与pH值、反应温度、反应时间、底物浓度、酶与底物浓度比之间的数学模型；并获得最佳水解工艺条件：pH值6．5，温度40℃，水解时间10h，底物浓度14％，酶与底物浓度比4．5％；主成分分析表明，pH对DH的贡献率最大。     

复合酶法水解蟹肉的研究

研究碱性蛋白酶和复合风味蛋白酶水解螃蟹肉的工艺条件。探讨了时间、酶用量、初始pH值、固液比浓度和温度对螃蟹肉水解效果的影响。在单因素试验的基础上,通过多因素响应面设计实验,获得最适水解工艺条件为时间4h、碱性蛋白酶先水解1h后再加入复合风味蛋白酶共同作用、初始pH值为8.3,固液比浓度为1∶2.5,温度60℃,碱性蛋白酶用量为1.2×10-3AU/g(蛋白质)、复合风味蛋白酶用量1.5LAPU/g,此时蛋白质的水解率为22.8%,TCA可溶性氮增长率含量为40.47%。     

中性蛋白酶和碱性蛋白酶对玉米蛋白水解作用的研究

本实验研究了中性蛋白酶和碱性蛋白酶分别作用和共同作用对玉米蛋白粉中玉米蛋白的水解效果.结果表明,中性蛋白酶水解玉米蛋白的较佳水解条件是:酶浓度3544U/g、pH7.0、温度55℃、水解时间(t)为2h,碱性蛋白酶水解玉米蛋白粉的较佳水解条件是:酶浓度840U/g、pH8.0、温度55℃、水解时间2h.采用中性蛋白酶和碱性蛋白酶复合水解玉米蛋白比单一酶水解的效果好,水解液的水解度达到20%以上.     

鲢鱼蛋白水解物的双酶法制备工艺优化

利用双酶法(Alcalase碱性蛋白酶与Flavourzyme复合风味蛋白酶)制备鲢鱼蛋白水解物,应用响应面分析法对酶水解工艺优化,最佳酶解条件为底物浓度为料水比1∶2,Alcalase碱性蛋白酶用量为0.4%,Flavourzyme复合风味蛋白酶用量为0.8%,水解温度60℃,水解pH值6.5,水解时间4h,此条件下水解度为65.2%。     

微波双酶水解鸡肉的研究

微波加热条件下,利用双酶法水解鸡肉的最佳酶解条件为：底物质量分数为15.0%、Flavourzyme复合风味蛋白酶和Protamex复合蛋白酶的质量分数均为0.6%、水解pH值6.5,水解温度55℃,酶水解时间70min,此条件下水解度为28.1%。     

Protamex复合蛋白酶酶解猪骨粉最佳条件研究

以SN-TCA指数法作为多肽生成量的评价指标,研究Protamex复合蛋白酶酶解猪骨粉的最佳条件,正交实验结果表明,最佳工艺参数是酶用量0.40g,水解时间12h,pH为7,水解温度为50℃.     

复合蛋白酶水解海参生殖腺工艺的研究

结合实际生产和复合蛋白酶的特性,本文研究了复合蛋白酶水解海参生殖腺的工艺及条件。本工艺省去了传统工艺的pH控制,酶解温度采用程序升温,45～65℃。通过单因素和正交实验分析了酶用量、底物浓度及时间对生殖腺水解的影响,确定其最佳水解条件为:底物浓度13%,酶浓度0.4%,时间2.5h。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.