酶解结合超声波辅助技术提取纯化菊米总黄酮

采用纤维素酶酶解结合超声波辅助提取,通过大孔树脂分离、纯化菊米中的黄酮类化合物,并通过单因素试验和正交试验进行工艺优化。结果表明：纤维素酶最佳酶解条件为料液比1:10(g/mL)、酶用量1.5%、酶解温度40℃、pH6.0、酶解时间6h;超声波辅助最佳提取条件为乙醇体积分数70%、提取时间0.5h。以自然流速过大孔树脂D-101 柱,经水洗除杂、60% 乙醇溶液洗脱,获得菊米提取物得率达7%,黄酮类物质含量50% 以上。     

纤维素酶法提取花生红衣中的白藜芦醇

目的:研究纤维素酶解法提取花生红衣中白藜芦醇的工艺条件.方法:在单因素试验基础上,采用L9(34)正交试验法对花生红衣白藜芦醇的酶法提取工艺进行优选.以白藜芦醇的得率为参考指标,考察酶用量、酶解温度、酶解时间、酶解pH值和乙醇浓度对花生红表白藜芦醇得率的影响.结果:最佳工艺条件为:纤维素酶与花生红衣粗粉的配比为1:500,酶解温度50℃,酶解pH 5.0,酶解时间90 min,提取溶剂乙醇的体积分数为60%.在此条件下白藜芦醇的得率为1.25%.与传统醇提工艺相比,其提取率提高了4.43倍.结论:该工艺是纤维素酶法提取花生红衣白藜芦醇的最佳工艺.     

酶法提取金樱子总黄酮的研究

对金樱子黄酮类化合物的酶法提取工艺进行了研究.采用单因素实验考察了纤维素酶、果胶酶、木瓜蛋白酶、复合酶(纤维素酶+果胶酶+β-葡聚糖酶+半纤维素酶+木瓜蛋白酶)对总黄酮提取率的影响及酶解温度,酶解液pH值,酶解时间和酶用量对总黄酮产量的影响,通过正交试验设计确定了酶法提取金樱子总黄酮的最佳提取工艺条件:酶解温度为50℃,酶解液初始pH=4.5,酶解时间为120min,酶的用量为0.35mg/mL的复合酶(纤维素酶+果胶酶+β-葡聚糖酶+半纤维素酶+木瓜蛋白酶).实验结果表明:在一定条件下,复合酶的酶解效果比单一酶好,纤维素酶酶解效果比果胶酶好,木瓜蛋白酶在单独使用时基本没有效果.根据正交实验确定的最佳酶提取工艺条件与传统的直接醇提取工艺相比,金樱子总黄酮产量提高了26.2%.     

南瓜果胶不同提取方法的研究

以南瓜果肉为材料,采用咔唑比色的方法,通过正交试验,分别研究超声波法、纤维素酶法和离子交换树脂法提取南瓜果胶的最佳提取条件。结果表明：超声波法的最佳提取工艺条件为：超声波功率400W,时间35min,液料比10:1(ml/g),果胶得率5.98%;纤维素酶法提取果胶的最佳工艺条件为：酶解时间2.0h,pH4.5,酶解温度55℃,加酶量0.5%,果胶得率9.56%;离子交换树脂法提取果胶的最佳工艺条件为：树脂用量15%,料液比为1:20(g/ml),pH2.5,时间2.0h,温度80℃,果胶得率7.62%。三种提取方法进行比较,纤维素酶法果胶得率最高,为南瓜果胶的最佳提取工艺。     

花椒籽可溶性膳食纤维的提取工艺研究

以脱脂花椒籽为原料,采用单因素实验和响应面法优化酶法提取花椒籽可溶性膳食纤维的工艺研究,并对制得的可溶性膳食纤维的理化性质进行了测定。结果表明,酶法提取花椒籽可溶性膳食纤维的最佳工艺条件为:纤维素酶添加量2.0%,料液比1∶23,酶解温度42℃,酶解时间13 h,酶解pH 4.33,胰蛋白酶添加量0.4%。在最佳工艺条件下,花椒籽可溶性膳食纤维的平均得率为9.19%,持水力为2.33 g/g,膨胀率为2.05 mL/g。     

花椒籽油水酶法提取条件优化研究

以纤维素酶和中性蛋白酶为主要提取剂,研究花椒籽油提取最佳工艺。结果表明,当纤维素酶和中性蛋白酶的比例为1∶10时,提取率较高。影响花椒籽油提取率的因素主次依次是:酶解温度>酶解时间>酶解p H>酶用量;最佳工艺条件为:混合酶用量8%,酶解时间4h,酶解p H7.0,酶解温度为45℃,在此参数下,花椒籽油的提取率最高,达到17.84%。     

双酶酶解法提取姜油树脂工艺优化

研究采用纤维素酶和半纤维素酶共同酶解姜粉提取姜油树脂的最优提取工艺。以姜辣素的提取率为指标,通过单因素和正交试验,确定姜油树脂的最优提取工艺。结果表明:纤维素酶-半纤维素酶质量比5:3,混合酶用量2.8mg/100mL,酶解时间2.5h、酶解温度45℃。验证实验表明该方法所得姜辣素提取率3.711%,比乙醇溶剂浸提法的姜辣素提取率提高了30%。采用酶综合调控技术可以较高程度地提高姜辣素的提取率。     

响应面法优化杏鲍菇多糖提取工艺

对杏鲍菇内多糖的提取条件进行研究,首先采用单因素法对影响酶解杏鲍菇水溶性多糖含量的因素以及酶解条件进行选取,然后在单因素试验的基础上,采用响应面法对杏鲍菇多糖的提取工艺进行优化,确定杏鲍菇多糖提取工艺的最佳参数,为其进一步的开发利用提供参考,杏鲍菇经过打浆、酶解后,通过水提醇沉的方法进行多糖的提取。结果表明:酶加量、料液比、pH值、酶解温度和酶解时间对多糖的提取具有明显的影响。杏鲍菇的最佳提取工艺参数为:纤维素酶0.9%、中性蛋白酶0.2%、料液比1∶2(g/mL)、pH 5.5、酶解温度50℃、酶解时间3 h,在该条件下杏鲍菇多糖提取率为3.24%。     

花椒麻味成分的提取与分离技术

花椒是我国特有的、资源丰富的一种调味品和中药原料 ,辛麻味是其主要的风味特征。文中通过单因素和正交试验确定了超临界CO2 萃取花椒麻味成分的最佳工艺条件为 :原料粒度 60目 ,萃取时间 2h ,流量 2 1kg/h ,温度 5 5℃ ,压力 3 6MPa,油树脂得率达 1 2 83 %。采用超临界CO2分离花椒油树脂中麻味成分的适宜工艺条件为 :分离器Ⅰ分离压力 1 2MPa,温度 40℃。分离器Ⅰ花椒油树脂得率为 1 85 % ,其中挥发油含量为 60 0 2 8mg/g。试验结果表明 ,采用此工艺可对花椒麻味成分进行有效地提取与分离     

纤维素酶法提取黑豆皮色素的工艺研究

研究了黑豆皮色素的酶法提取工艺.以黑豆皮色素的提取率为指标,采用单因素法和正交设计法对纤维素酶法提取工艺条件进行优选.实验结果表明,最佳提取工艺条件为:酶用量80U/mL,酶解温度50℃,pH4.5,酶解时间120min;该工艺条件下进行三次浸提,色素提取率达到96.8%,与未加纤维素酶的工艺相比,提取率提高了8.2%.     

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.