复合果蔬汁饮料青椒苹果汁的研制

主要研究青椒苹果汁饮料的制作方法,确定其基本配方为：苹果原汁10%～20%、青椒原汁10%、白砂糖8%～10%、柠檬酸0.3%、柠檬酸钠0.05%。苹果原汁生产中采用抗坏血酸护色与微波灭酶相结合,具有较好的抗褐变效果。青椒原汁生产中采用果胶酶提高青椒出汁率,效果显著。最佳酶解条件为：果胶酶添加量0.01%、加水量40%、酶解温度50℃、酶解时间40min、酶作用pH3.0,此条件下青椒出汁率可提高至57%,比未经酶处理的出汁率23.4%高出33.6%。     

响应面法优化酥李果汁的酶法提取工艺

目的:研究酶解提取酥李果汁的最佳工艺条件,为李深加工利用提供理论参考。方法:以酥李出汁率为指标,在单因素实验基础上采用响应面试验优化,对单一果胶酶、单一纤维素酶、复合酶（果胶酶和纤维素酶）提取酥李果汁的工艺条件分别进行优化。结果:不同加酶方式中对酥李出汁率的影响因素顺序均为酶解温度>加酶量>酶解pH>酶解时间;果胶酶酶解提取酥李果汁的最佳工艺条件为:加酶量0.45 g/L、酶解温度38 ℃、酶解pH3.8、酶解时间72 min,出汁率提高27.13%;维素酶酶解提取酥李果汁的最佳工艺条件为:加酶量0.55 g/L、酶解温度41 ℃、酶解pH4.2、酶解时间105 min,出汁率提高20.18%;复合酶酶解提取酥李果汁的最佳工艺条件为:果胶酶添加量0.45 g/L、纤维素酶添加量0.55 g/L、酶解温度41 ℃、酶解pH4.0、酶解时间87 min,出汁率提高31.79%。三种加酶方式中,回归模型均能较好地反应相应酶制备酥李果浆的出汁率,所得工艺合理可靠。结论:在酶法提取酥李果汁过程中,果胶酶和纤维素酶的不同添加方式均能有效提高酥李出汁率,其中采用复合酶提取酥李果汁效果最佳。本研究成果为贵州李产品开发提供了一定的技术参考。     

酶法提高草莓出汁率的研究

分别采用果胶酶、蛋白酶和纤维素酶单一酶剂酶解草莓果浆,结果表明,果胶酶用量0.08%,25℃酶解30 min,出汁率可达85%以上,出汁率提高26.7%,而添蛋白酶和纤维素酶对出汁率提高不显著,仅分别提高7.8%和10.2%。采用果胶酶、蛋白酶和纤维素酶协同酶解,结果表明,25℃酶解30 min,出汁率可达98.7%,出汁率提高30.4%,突破单一酶剂果汁溶出不完全的瓶颈。     

响应面优化酶法提取沾化冬枣汁的工艺研究

为提高沾化冬枣的出汁率,采用酶解法对冬枣进行处理,确定复合酶(果胶酶和纤维素酶)的效果优于单一酶,并确定复合酶的质量比为1∶2时效果最好。同时,在单因素试验基础上,采用Box-Behnken响应面设计优化冬枣汁酶法提取工艺,研究酶用量、酶解时间、酶解温度对冬枣出汁率和可溶性固形物含量的影响。试验结果表明,酶用量为0.1%、酶解时间为68 min、酶解温度为50℃,在此条件下出汁率可达到(72.27±0.3)%、可溶性固形物含量为(8.0±0.2)%,与预测结果基本相符。     

酶解草莓浆制汁工艺研究

本研究采用果胶酶及纤维素酶共同作用酶解草莓后再榨汁，与常用的制汁方法比较，其出汁率提高了１０￣２０％，通过正交试验得到了最佳酶解条件：果胶酶０．２‰，纤维素酶０．６‰，ＰＨ３．３，４５℃保持１２０分钟，同时，对该条件下的草莓清汁进行了主要质量指标分析。部分指标也有所提高。为合理选择制汁工艺流程提供了实验依据。     

狼尾草复合酶酶解参数优选研究

研究果胶酶和纤维素酶复合酶解狼尾草对出汁率的影响效果。通过果胶酶用量、纤维素酶用量以及时间三因素的单因素试验。在单因素试验基础上,运用二次旋转组合设计正交,选取纤维素酶、果胶酶和时间为实验因素,确定复合酶酶解提高狼尾草出汁率的最佳工艺参数。实验结果表明,在45℃时,纤维素酶用量1.14%,果胶酶用量0.6%,时间4.5 h达到最大值86.11%。     

果胶酶和纤维素酶对芒果出汁率及品质的影响

为提高芒果的出汁率,采用果胶酶和纤维素酶对芒果浆进行酶解,通过正交实验研究了果胶酶添加量、纤维素酶添加量、酶解温度、酶解时间4个因素对芒果出汁率的影响。结果表明:当果胶酶添加量为0.01%、纤维素酶添加量为0.007%、酶解时间为60min、酶解温度为40℃时,芒果的出汁率最高,达到71.15%;酶解得到的芒果汁可溶性固形物为16.7%±0.1%,可滴定酸为0.51%±0.08%,类胡萝卜素为(1.23±0.07)mg/100g,还原糖为7.6%±0.08%,果胶含量为(357±1.32)mg/100g,保留了鲜芒果的营养成分。     

不同酶解工艺对珍珠油杏出汁率的影响

试验以珍珠油杏为原料,经过清洗、解冻和打浆之后,加入酶进行酶解,分别对单一果胶酶酶解工艺和果胶酶与纤维素酶复配酶解工艺进行优化,考察优化条件对珍珠油杏杏浆出汁率的影响.经过单因素试验和正交优化试验,最终确定的最佳单一果胶酶酶解工艺条件是果胶酶添加量0.035％、酶解温度45℃、酶解时间120 min,此时珍珠油杏杏浆出...     

酶法制取甜柿浑浊果汁的工艺研究

采用果胶酶和纤维素酶液化甜柿果浆来制取浑浊果汁。通过正交实验得到了酶解制取甜柿果汁的最佳工艺参数：纤维素酶用量6500 U/200g(果肉),果胶酶用量2500u/200g(果内),酶解温度45℃,酶解时间 2．5h,果汁出汁率达到了79%。     

复合酶对草莓出汁率和澄清度的影响

为提高草莓的出汁率和草莓汁的澄清度,该文以新鲜草莓为原料,研究单一酶（果胶酶、纤维素酶、木聚糖酶）和复合酶对出汁率和澄清度的影响。在单因素试验基础上,对复合酶添加量、复合酶质量比、酶解温度、酶解时间进行响应面优化,得到最佳酶解条件,并对酶解的草莓汁进行感官评价。结果表明,果胶酶和纤维素酶具有协同作用,可明显提高草莓的出汁率和澄清度,出汁率从64.16%（对照组）提高到87.38%,澄清度从2.34%提高到72.83%;经响应面优化试验,得到草莓汁最佳酶解条件为复合酶添加量0.17%、复合酶（果胶酶∶纤维素酶）质量比3∶1、酶解温度41℃、酶解时间35 min,此条件下草莓的出汁率为90.84%,草莓汁的澄清度为84.61%;与对照组相比,复合酶组的感官评分最高,整体风味及口感更优,表明果胶酶和纤维素酶可以有效提高草莓的出汁率和澄清度,且所得草莓清汁感官风味更佳。     

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