超声辅助乙醇提取海带多酚工艺优化及抗氧化活性

探究超声辅助乙醇提取海带多酚的工艺条件,选取超声温度、料液比、超声时间和乙醇浓度为试验因子,研究不同工艺参数对海带多酚提取量的影响,并采用响应面法优化海带多酚的提取工艺,通过测定其对DPPH自由基及ABTS的清除作用,评价其抗氧化活性。结果表明,超声辅助乙醇提取海带多酚的最佳工艺条件为:超声温度65.0℃、料液比1∶28(g/mL)、超声时间45min、乙醇浓度75%,在此条件下海带多酚提取率为2.118 mg/g,接近模型预测值2.139 mg/g。海带多酚对DPPH自由基和ABTS的清除率分别为68.87%和49.73%,IC_(50)相应为81.119μg/mL和222.224μg/mL,其清除能力与多酚浓度之间呈一定的正相关关系,海带多酚具有一定的体外抗氧化能力。超声波辅助乙醇提取海带中多酚的方法可行、可靠,试验为海带生物活性成分的高效制备与抗氧化剂的深度开发提供了理论依据。     

溶剂浸取法提取麻疯果仁油的工艺研究

采用溶剂浸取法提取麻疯果仁油,考察了浸取温度、浸取次数、液料比、浸取时间等因素对提油效果的影响。实验得到的最佳逆流浸取工艺条件为:浸取温度60℃,浸取级数5级,液料比8∶1,单级浸取时间1 h。在该工艺条件下,麻疯果仁油的提取率可达99.1%,脱溶后所得毛油酸值(KOH)在2.8~4.2 mg/g之间,可直接用作制备生物柴油的原料油。     

桑葚花青素乙醇浸提工艺优化研究

以桑果干为原料,采用乙醇溶剂浸取法提取桑葚中的花青素,采用pH示差法测定花青素含量,探究料液比、乙醇浓度、提取温度、提取时间和pH对花青素提取量的影响,通过单因素试验和正交试验设计优化乙醇溶剂浸取工艺,并通过验证试验分析得到最佳提取工艺条件。最佳提取工艺条件为:乙醇体积分数为55%,料液比为1∶10(g/mL),提取温度为60℃,提取时间为120min,溶剂pH为4.0,得到桑葚花青素提取量为2.53mg/g。乙醇溶剂浸取法简便易行,设备投入少,成本低,适用于桑葚花青素的提取。     

山黄皮果仁挥发油提取工艺研究

研究山黄皮果仁挥发油的提取工艺.以挥发油得油量为考察指标,以浸泡时间、加水量、提取时间为考察因素进行正交试验.提取时间对挥发油的提取影响最大,最佳提取工艺条件为:浸泡4h,加水20倍,提取6h.研究山黄皮果仁挥发油的提取工艺,为合理开发和利用资源提供了依据.     

海带生物有机碘的急性毒理学评价研究

采用半数致死量的测定、微核实验、小鼠精子畸变试验、Ames试验等方法,评价研究海带中提取的生物有机碘的急毒性食品毒理学效应,为科学开发补碘保健食品提供科学依据。结果表明,Horn氏法求得海带生物活性碘的LD50>10000mg,为实际无毒物质;微核实验结果表明,海带生物有机碘对小鼠骨髓细胞无致突变作用;小鼠精子畸变试验结果表明,海带生物有机碘不引起小鼠精子畸形;Ames试验结果表明,海带生物有机碘无诱发细菌基因突变作用,是一种安全的食品补碘剂。     

杏仁精油提取工艺研究

为确定水蒸气蒸馏提取杏仁精油的工艺参数,以正交试验和单因素试验相结合的方法对影响杏仁精油提取率的水解时间、水解温度、蒸馏时间、加水量以及水解pH等因素进行了研究。结果表明:杏仁精油提取的最佳工艺为:水解时间1h,水解温度40℃,蒸馏时间60min,加水量1000mL,水解pH5。各因素影响杏仁油出油率的顺序为:加水量>水解温度>蒸馏时间>水解pH>水解时间。最佳工艺验证试验的杏仁精油得率为7.25‰。本研究结果为纯天然杏仁精油的提取工艺提供了技术参数。     

超声波辅助法提取米糠多糖的工艺研究

研究超声波辅助提取米糠多糖中温度、时间、加水量、超声功率对多糖提取率的影响,通过单因素实验和正交实验发现,温度对多糖提取率的影响最大,功率对多糖提取结果的影响最小,超声波辅助提取米糠多糖的最佳工艺条件为:温度80℃、时间70min、加水量20倍、功率200W,此时米糠多糖的提取率为1.75%,比热水法的提高了66.98%。     

蚕豆皮原花青素提取工艺优化

以蚕豆皮为材料,探讨微波预处理-乙醇提取法提取原花青素的工艺条件。分别考察预处理工艺中微波功率、微波时间、加水量,提取过程中的料液比、提取温度、提取时间对原花青素提取率的影响。结果表明：微波预处理-乙醇提取最佳工艺为微波功率140W、微波处理时间50s、加水量2mL/g、液料比21:1(mL/g)、温度55℃、70%乙醇溶液提取72min,原花青素提取率为94.53%。     

杨梅红色素的提取工艺研究

以新鲜杨梅为原料,以红色素的吸光度值为评价提取率的指标,在单因素实验的基础上,选用L9(34)进行正交实验,考察盐酸含量(%)、浸取温度、浸取时间、浸取物料比四因素对杨梅红色素提取工艺的影响.结果表明,杨梅红色素的较佳提取工艺条件为:盐酸浓度为0.30%,浸取温度为60%,浸取时间为40min,浸取物料比为1:10.在此工艺条件下,杨梅红色素得率为13.7%.     

高品质油茶籽油的湿法提取工艺优化

为了获得富含生物活性成分的高品质油茶籽油,采用湿法提取油茶籽仁中油脂,并采用响应面实验优化工艺条件。结果表明:最佳工艺条件为加水量12%、提油助剂添加量1%、提取温度55 ℃、提取时间50 min;在最佳工艺条件下,油茶籽仁的提油效率达86%以上,所得油脂基本不含固杂,其中的生物活性成分维生素E、角鲨烯和谷甾醇含量分别高达189.0、221.9 mg/kg和385.2 mg/kg,高于T/LYCY 001—2020《特、优级油茶籽油》中优级油茶籽油的相应指标值,为高品质油茶籽油产品的开发提供了新思路。     

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