水酶法提取榛子蛋白工艺优化

以榛子仁为原料,利用Alcalase碱性蛋白酶水解,进而提取榛子蛋白。以榛子仁总蛋白提取率为指标,对影响因素进行研究。在单因素试验的基础上采用响应面法优化工艺条件,得到最佳酶解条件：加酶量2.0%、温度55℃、酶解时间2.5h、料水比1:5(g/mL)、pH8.9。由F检验可得因素贡献率为x1＞x2＞x4＞x5＞x3,即加酶量＞酶解温度＞料液比＞酶解pH值＞酶解时间。     

水酶法提取榛子油工艺条件研究

以东北特产榛子为原料,对用水酶法提取榛子中的油脂工艺条件进行研究。在单因素试验的基础上,通过正交试验得出最佳工艺条件为酶解pH7．5、酶解温度45℃、加酶量2％、料液比1：5。此条件下提油率为85．2％。水酶法所得榛子油为黄色、澄清透明。     

水酶法提取黄粉虫油工艺优化

对碱性蛋白酶和胰蛋白酶复合水解黄粉虫提取黄粉虫油的工艺条件进行了研究。在酶解时间、加酶量、液料比、温度、pH五个单因素试验的基础上,以提油率为评价指标,利用响应面分析法优化了温度、加酶量、pH等酶法提取黄粉虫油的条件。优化的工艺条件为:酶解温度50.04℃,加酶量799.38U/g(原料),pH8.49,液料比5:1,酶解时间120min,此条件下提油率为78.51%。水酶法提取黄粉虫油品质优于石油醚提取,采用GC-MS法对黄粉虫油脂肪酸组成进行分析,共检出18种脂肪酸,其不饱和脂肪酸含量高达76.22%。     

水酶法提取油莎豆油的工艺研究

以油莎豆为原料,采用水酶法建立一种油莎豆油提取新工艺.通过单因素和正交试验,对水酶法提取油莎豆油的工艺进行了优化.结果表明,最佳提油工艺为:料液比1:7,加酶量0.4%,酶解温度40℃,酶解时间10 h.在此条件下提油率高达86.82%.在上述影响因素中,混合酶的添加量为主要影响因素,其次是酶解温度,再次是料液比,酶解时间影响最小.     

酶法提取黑加仑籽油

对于酶法提取黑加仑籽油进行了初步探讨。经对比实验筛选出从黑加仑籽中提油的3种酶:复合纤维素酶、果胶酶和中性蛋白酶。通过正交实验分别对3种酶的酶解条件进行优化,得到的结果为,果胶酶:添加量0.5%,pH 6,酶解时间4 h,料液比1∶5,酶解温度50℃,在此条件下提油率为8.03%;复合纤维素酶:添加量1.5%,pH 6,酶解时间4 h,料液比1∶6,酶解温度55℃,在此条件下提油率为10.73%;中性蛋白酶:添加量1.0%,pH 8,酶解时间5 h,料液比1∶5,酶解温度45℃,在此条件下提油率为11.43%。将3种酶复合使用后提油率达到13.89%,显示复合酶法的提取效果要好于单一酶法。     

超声波辅助水酶法提取花生油工艺

采用水酶法结合超声波预处理提取花生油,在单因素试验基础上,选出最优的超声时间(20min)和超声温度(45℃),重点以加酶量、酶解pH、酶解温度、酶解时间和料液比为影响因素,以花生提油率为响应值,采用响应面试验确定最优水酶法提取花生油工艺条件为:加酶量1.7％,酶解温度56℃,酶解时间3.8h,料液比1∶4,酶解pH 9.3.在最优条件下,响应面有最优值(95.50 ±0.44)％.     

水相法提取牡丹籽油及破乳工艺的研究

采用水相法提取牡丹籽油,碱提形成稳定乳状液后,用酶和乙醇进行破乳。选择料液比、酶活添加量、酶解时间、酶解温度作为试验的四个因素,在单因素试验的基础上,进行四因素三水平的正交试验优化提油工艺。通过极差分析可看出,四个因素对牡丹籽出油的影响大小为:料液比酶活添加量酶解温度酶解时间。通过正交工艺优化,得出最佳的提油工艺为:料液比1︰6(g/m L)、酶活添加量600 U/g、酶解时间2.5 h、酶解温度60℃。在此优化条件下,牡丹籽出油率可达到17.13%。提油率为62.29%。     

水酶法提取胡麻籽油工艺条件的研究

采用水酶法提取胡麻籽油并对其工艺条件进行了详细研究。在单因素实验的基础上,通过正交实验得出了最佳工艺条件,即20 g研碎油料,加酶量为0.10 g,酶解温度50℃,酶解时间1h,最适pH 5.4,料液比1∶10,浸提温度90℃,浸提时间9 h。另外,水酶法提取胡麻籽油的提油率比水浸法提取胡麻籽油的提油率高24.55%。     

响应面法优化水酶法提取松子油的研究

用Alcalase碱性蛋白酶对松子仁进行水解,提取松子油,试验以总油提取率为指标,采用单因素试验对酶解温度,加酶量,料液比,酶解pH和酶解时间5个影响因素进行了研究,并用响应面法进行了优化。上述影响因素中,酶解温度为主要的影响因素,其他依次为加酶量,料液比,酶解pH,酶解时间。本试验优化后得到的最佳酶解条件为:加酶量1.97%,温度51℃,时间3.0 h,料水比1∶5,pH 8.4,松子总油提取率可达89.12%。测定松子油的5种脂肪酸的质量分数分别为,棕榈酸3.89%,硬脂酸1.53%,油酸19.44%,亚油酸50.09%,亚麻酸0.58%。     

水酶法提取光皮树油的研究

从市售的木聚糖酶、淀粉酶、纤维素酶、中性蛋白酶、复合植物水解酶、果胶酶中筛选提取光皮树油的水解酶,实验结果得到纤维素酶对光皮树果实的提油作用最强,其提油率达65.29%,复合植物水解酶次之,为64.05%,木聚糖酶效果最差,仅为54.47%。通过单因素实验得到纤维素酶提取光皮树油的最适工艺条件为:酶解pH 5.8,料液比1∶3,酶加量2.5%,酶解温度40℃,酶解时间4h。该条件下,油的乳化率低,提出来的基本上是清油,且提油率达76.64%。     

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.     

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.     

European priorities for research to support legislation in the area of food contact materials and articles

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.     

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