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1.
以麦麸为实验材料,采用内源植酸酶降解麦麸中的植酸.以植酸的残余含量为指标,在研究温度、pH值、时间单因素对内源植酸酶降解植酸效果影响的基础上,通过正交实验确定内源植酸酶降解植酸的最佳条件为:温度55℃,pH4.6,降解6 h,在此条件下植酸的残余含量为1.032 4%.并与蒸煮法降解植酸比较.蒸煮6 h后植酸含量为2.312 2%.说明内源植酸酶法较蒸煮法可较好地降解植酸.  相似文献   

2.
菜籽饼粕中植酸新提取方法研究   总被引:9,自引:1,他引:9  
本文研究了沉淀剂法直接从菜籽饼粕中提取植酸。结果表明:碳酸钠、磷酸钠和草酸盐等三种沉淀剂中,以草酸盐溶液提取植酸的效果最好;当以草酸盐为提取剂时,提取最佳工艺条件为草酸盐浓度为0.05mol/L、pH为6.5-7.5、料液比为1:8-1:10、温度为30℃、浸提时间为3h。本文还详细地探讨了沉淀剂法提取菜籽饼粕中植酸的原理。  相似文献   

3.
利用发芽大麦的植酸酶去除大豆中的植酸。试验表明:将发芽3d的大麦与浸泡1d的大豆以6:4的比例混合粉碎后,在55-60℃,pH=5,5条件下酶解3h,麦豆混合物中植酸去除率可达93%以上。  相似文献   

4.
酶法去除大豆植酸的正交分析   总被引:1,自引:0,他引:1  
利用大麦浸泡萌发时其内部的植酸酶去除大豆中的植酸。在单因素基础上进行正交试验,将侵泡1d大豆与发芽3d大麦4:6混合,打浆后,在60℃,pH值6.0条件下酶解3h麦豆混合物中植酸去除率可达96%。  相似文献   

5.
本文综合报导WRD-87菜籽饼粕脱毒制取蛋白饲料工艺的研究结果。全文分为三个部分。第一部分实验室工作介绍,第二部分该工艺的中试放大及专用成套脱毒设备的研制,第三部分技术经济分析。实验表明,WRD-87工艺是一种十分有效的菜籽饼粕脱毒工艺。菜籽饼粕经其处理后同时可得脱毒饼粕或浓缩菜籽蛋白粉和液体有机肥料。毒物硫甙及其分解产物可脱除95%以上,残留总硫甙不足0.1%,植酸脱除率在90%以上,其它抗营养成分也大多被脱除。日处理8吨饼粕时,每千克菜籽饼粕处理成本不大于4分钱。脱毒排放液含有丰富的植物营养素,具有一定的预防作物病虫害作用,是一种优质液体有机肥料。脱毒饼粕经肉鸡和蛋鸡饲喂实验证明,动物适口性好,饲养价值高,可用来代替鸡正常日粮中60%以上的鱼粉或豆饼,具有十分显著的社会经济效益。  相似文献   

6.
论述了菜籽饼粕脱除硫甙、植酸以及酚的各种方法,并对菜籽浓缩蛋白的制取方法进行了简要评述。  相似文献   

7.
大麦内源酶去除大豆植酸的正交实验研究   总被引:1,自引:0,他引:1  
利用发芽大麦的植酸酶去除大豆中的植酸。实验表明,将发芽3d的大麦与浸泡1d的大豆以6∶4的比例混合粉碎后,在60℃,pH6.0条件下酶解3h,麦豆混合物中植酸去除率可达96%以上。  相似文献   

8.
热激处理和柠檬酸提高发芽糙米中植酸酶活性   总被引:1,自引:0,他引:1  
李欣  陈威  何敏 《食品工业科技》2014,(8):202-205,209
研究了热激处理和柠檬酸发芽介质对糙米的内源植酸酶活性的影响,并采用响应面设计优化了热激处理条件。结果表明,随着热激时间的延长,糙米中植酸酶的活性逐渐升高,达到峰值后下降。利用中心组合响应面设计实验,预测并验证的优化的热激和浸泡条件为,热激温度50℃,热激时间30min,浸泡时间6h。以2mmol/L柠檬酸缓冲液(pH5.2)作为发芽介质,植酸酶活性随着发芽时间的延长,先升高后下降;发芽3d,植酸酶活性达到最高值(241.27U/kg),高于原料糙米(115.57U/kg)。本工艺提高了发芽糙米的内源植酸酶活性,为开发糙米食品中降低植酸和保持营养价值的提供了基础数据。  相似文献   

9.
双低油菜籽浓缩蛋白的制备及其功能特性的研究   总被引:4,自引:2,他引:4  
通过响应曲面法,确定以含水乙醇洗涤法制备双低菜籽浓缩蛋白的最佳工艺参数为:选用浓度为70%的乙醇做溶剂,控制液固比为8.85:1,在60℃温度搅拌下,洗涤次数为6次,洗涤时间为20min/次。该工艺条件下制备的菜籽浓缩蛋白,其色浅味淡,无溶剂残留。蛋白质含量可达62.48%,其中硫甙能够完全脱除,植酸含量下降了60%。研究并对菜籽浓缩蛋白的溶解性、吸水性、吸油性、乳化性和起泡性等功能特性及功能特性的改善进行了研究。  相似文献   

10.
菜籽饼粕脱毒工艺参数的研究   总被引:7,自引:5,他引:7  
以菜籽饼粕为研究对象,采用硫酸甲醇溶液为脱毒体系,确定了该法脱毒的最佳工艺参数:硫酸:甲醇:水=4%:90%:6%(体积比)的混合液为脱毒体系,与菜籽饼粕的混合比为8:1(mL/g),室温下浸提30min。植酸提取率近90%,单宁提取率和硫代葡萄糖甙(简称硫甙)的去除率均超过80%,粕中硫甙的含量可降到2mg/g以下,满足饲料标准的要求;也达到了同时提取植酸和单宁的目的。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
17.
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.  相似文献   

18.
19.
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.  相似文献   

20.
<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  相似文献   

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