响应面法优化沙棘籽油微胶囊制备工艺

目的 优化沙棘籽油微胶囊制备工艺。方法 以包埋率为评价指标,选择均质压力、进风温度、进样速率3三个因素,采用Box-Behnken方法设计因素、水平,通过响应面分析法确定沙棘籽油微胶囊制备工艺最佳条件。结果 沙棘籽油微胶囊最佳制备工艺为：进风温度174℃、均质压力34.8 MPa、进风温度174℃、进样速率17 mL/min。在此条件下进行3三次重复实验试验,测得沙棘籽油微胶囊包埋率的平均值为93.25%,与预测值93.59%接近,响应面试验模型可靠性高具有较好重现性。沙棘籽油微胶囊后可以减缓沙棘籽油的氧化速率。结论 进风温度174℃、均质压力34.8 MPa、进样速率17 mL/min经最优工艺制备出的沙棘籽油微胶囊可以有效阻隔沙棘籽油与空气的接触,提升沙棘籽油的氧化稳定性,可为改善沙棘籽油加工稳定性提供参考。     

叶黄素微胶囊化研究

研究了以叶黄素晶体为芯材,用喷雾干燥法制备10%叶黄素微胶囊的配方和工艺。最佳配方为:叶黄素晶体(80%)质量分数12.5%、阿拉伯胶质量分数54.96%、蔗糖质量分数30.54%、低聚原花青素质量分数1%、迷迭香提取物质量分数1%。高压均质参数为90 MPa均质2次;喷雾干燥工艺参数为:进风温度170℃、气流压力170 kPa、进料流量400 mL/h、进料温度50℃。所得产品在40℃,相对湿度75%条件下放置10 d的含量保留率为97.8%,稳定性得到显著提高。     

沙棘籽粕蛋白的碱酶两步法提取工艺及功能性研究

以沙棘籽粕为原料,采用碱提酸沉法提取沙棘籽粕蛋白,得到最佳提取工艺参数为:pH10、料液比1:12、温度60℃、时间60min。后用碱性蛋白酶对碱提残渣中的蛋白进行水解,最适提取条件为:pH8.5、碱性蛋白酶加酶量240U/g、料液比1:10、60℃、60min。通过碱提、酶法两步提取后,总提取率为67.24%。并对其乳化活力和乳化稳定性等功能性质进行了研究,表明性质受pH、温度、盐离子浓度等环境因素影响大,在等电点pH5.0附近时乳化活力和乳化稳定性的数据最低。     

蚕蛹油不饱和脂肪酸提取及氧化稳定性研究

以蚕蛹毛油为原料,采用常压碱水皂化制取混合脂肪酸,溶剂法分离高纯度蚕蛹油不饱和脂肪酸。首先在超量碱、皂化温度、皂化时间单因素实验的基础上采用响应面实验优化常压碱水皂化工艺,得到最佳皂化条件为恒定碱液质量分数15%,超量碱45%,皂化温度98℃,皂化时间3.3 h;其次通过甲醇溶剂法得到高纯度蚕蛹油不饱和脂肪酸工艺条件为恒定结晶温度-10℃,料液比为1∶2.4(混合脂肪酸与溶剂甲醇质量比),甲醇溶液质量分数90%,结晶时间30 min;最后脱色后得到蚕蛹油不饱和脂肪酸产品,并对其理化指标测定。产品在不同贮存条件下保存32 d考察其氧化稳定性,结果表明在4℃条件下避光保存并添加抗氧化剂的产品稳定性最好。     

醇法提取沙棘籽蛋白的工艺研究

本研究以沙棘籽粕为原料,采用醇法提取沙棘籽蛋白,在单因素试验的基础上,通过正交试验优化工艺,讨论乙醇浓度、料液比、提取温度、提取次数对产品中蛋白质含量的影响。正交试验得到的最佳工艺参数为：乙醇浓度70%、料液比1∶7、提取温度55℃、提取5次。产品中蛋白质含量为55.18%,蛋白得率为78.65%。     

脱脂沙棘籽渣中原花青素的提纯与稳定性研究

在单因素实验基础上采用响应面优化法,确定了从脱脂沙棘籽渣中提取原花青素的最佳工艺条件为乙醇体积分数60%,温度35℃,pH1.5,提取时间1h,在此条件下原花青素的提取率为6.61%,纯度为38.63%;同时考察了原花青素粗产品的热稳定性和酸碱稳定性,结果表明,原花青素在温度大于50℃及碱性条件下不稳定,这同时也证明了最优实验条件的合理性;采用溶剂萃取法和AB-8大孔树脂吸附法对原花青素粗产品进行分离提纯,得到产品收率分别为0.5%与1.6%,纯度分别为81.2%与82.8%。     

沙棘原浆冷冻浓缩工艺的响应面优化

为了避免在热浓缩过程中沙棘原浆里V_C、含硫氨基酸等热敏性物质的损耗,缓解褐变现象。以沙棘原浆为试材,利用单因素实验研究冷冻浓缩加工过程中冷冻温度、沙棘浆浓度、冷冻时间对取冰质量、取冰纯度的影响。并采用Box-behnken响应面设计,进一步对冰晶质量和冰晶纯度进行联合优化。结果表明,经过响应面联合优化并验证后得到的最佳的工艺条件为:冷冻温度-7℃、沙棘浆浓度12.4 Brix、冷冻时间13 min,此条件下实际结晶强度为33.67 g,结晶纯度为8.1 Brix。此时能够在最经济的浓缩条件下得到最大的冰晶生成量,且冰晶纯度最高。通过对冷冻浓缩前后以及复原汁的营养成分对比得知,浓缩后沙棘汁的总酸、总可溶性固形物和总黄酮的含量显著上升,浓缩过程对各营养成分的损失均低于10%。     

沙棘酥性饼干的研制

选择沙棘籽粕粉、沙棘果皮粉、鸡蛋蛋白粉为主要材料,配合其他辅料研究开发富含蛋白质和膳食纤维的沙棘酥性饼干。采用单因素试验与正交试验相结合的方法,探讨了饼干生产中沙棘籽粕粉、沙棘果皮粉和鸡蛋蛋白粉添加量对饼干面团性能和成品感观品质的影响,得出了沙棘酥性饼干的最佳工艺配方:以小麦粉质量为100%计,沙棘籽粕粉6%、沙棘果皮粉9%、鸡蛋蛋白粉14%、黄油37%、白砂糖33%、水22%、小苏打1.4%、碳酸氢铵1.2%、奶粉10%、聚葡萄糖2%、饼干专用酶0.4%、大豆磷脂0.6%、食盐0.8%。由最佳配方制得饼干产品中蛋白质质量分数达到13.12%,膳食纤维质量分数达3.3%。     

沙棘籽油微胶囊的制备及氧化稳定性评价

沙棘籽油是一种富含不饱和脂肪酸的功能性油脂,容易氧化变质。本文将添加天然抗氧化剂与微胶囊制备技术相结合,改善沙棘籽油的氧化稳定性,延长货架期。首先测定了沙棘籽油的组成成分,然后以沙棘籽油为芯材,添加经过筛选的天然抗氧化剂L-AP,以辛烯基琥珀酸淀粉钠,酪蛋白酸钠及麦芽糊精等为壁材制备沙棘油微胶囊,并通过65 ℃烘箱加速保藏实验评价其氧化稳定性。结果表明:沙棘籽油中不饱和脂肪酸含量占总脂肪酸的80.6%±2.10%;制备沙棘籽油微胶囊的最佳配方为辛烯基琥珀酸淀粉钠15%、酪蛋白酸钠5%、麦芽糊精5%、抗性糊精30%、甘蔗浓缩汁10%、沙棘籽油30%、异麦芽酮糖5%,并添加3 g/L三聚磷酸钠,包埋率高达91.8%±1.59%;65 ℃烘箱加速保藏实验结果表明,添加抗氧化剂并制备微胶囊能有效提高沙棘籽油的氧化稳定性。     

响应面法优化红枣沙棘馒头的工艺研究

以中筋面粉、红枣、沙棘为主要原料研究红枣沙棘馒头的最佳工艺配方。基于单因素试验结果,采用 Plackett-Burman(PB)设计结合 Box-Behnken Design(BBD)响应面法试验,以质构特性(硬度、弹性、咀嚼性)、比容、色差(L*、b*)和感官评分为考察指标评价红枣沙棘馒头的品质,基于主成分分析法优化红枣沙棘馒头的加工工艺。结果表明：红枣沙棘馒头的最佳工艺配方为：以中筋面粉质量为基准,红枣泥10 %、沙棘汁3.5 %、酵母1.5 %、水40 %、发酵时间50 min、发酵温度38 ℃。在此工艺条件下所得规范化综合评分最高,验证试验与得出优选出的红枣沙棘馒头工艺条件具有很好的重现性,模型的预测性好,各项主要营养指标都符合国标。结果提示,PB设计结合 BBD响应面法方法可信度高,所优选的工艺稳定可靠,可作为红枣沙棘馒头工艺的优化方法。     

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