微胶囊化菠萝粉关键技术研究

以菠萝粉为芯材,阿拉伯胶和麦芽糊精为壁材,菠萝粉中总胡萝卜素的包埋率和Vc保留率为主要考察指标,通过乳化、均质、喷雾干燥等工艺,制备菠萝粉微胶囊,探讨喷雾干燥法制备菠萝粉微胶囊的工艺条件。通过单因素试验和正交试验确定最佳的工艺条件为:进风温度180℃,壁芯比8:50,壁材内部的配比(阿拉伯胶/麦芽糊精)1:12,入料流量15mL/min,所得微胶囊产品的包埋率为89.01%。     

猪血微胶囊技术及红豆血粉营养糊研究

以明胶和蔗糖为壁材,用喷雾干燥法对猪血进行微胶囊化,喷雾干燥适宜的工艺条件为:进风温度150℃ ,出风温度85℃.将微胶囊化的血粉配制成红豆血粉营养糊,最适宜的比例为:红豆粉65%、麦芽糊精20%、微胶囊化血粉15%、蛋白糖0.2%.为利用动物血,开发以血补血产品开辟了一条新的途径.     

包埋技术在速溶紫薯粉饮料生产中的应用

利用微胶囊包埋技术制备速溶紫薯粉,并确定了工艺条件。通过喷雾干燥制取速溶紫薯粉,采用单因素对比试验以及正交试验最终确定喷雾干燥的适宜工艺条件:包埋剂β-环状糊精添加量为总质量的0.25%;喷雾干燥工艺条件为:风速1 m3/min、进料量4 L/h、进口温度为130℃。     

微胶囊猪骨汤粉生产技术的研究

以猪骨汤中的脂肪为芯材,麦芽糊精、乳清粉、卡拉胶为壁材,对喷雾干燥法制备微胶囊骨汤粉的工艺条件进行研究。首先通过单因素试验和单纯形重心设计试验确定复合壁材之间的比例,即麦芽糊精:乳清粉:卡拉胶为55:35:10(m/m);然后通过单因素试验和正交试验,确定制备微胶囊骨汤粉的最佳工艺条件,即乳化温度55℃、乳化时间16min、壁材添加量25%、芯材添加量17%;制得的微胶囊骨汤粉为乳白色粉末,密度0.55g/cm3,含水量2.26%,溶解度92%。     

肉桂醛微胶囊的制备工艺

研究了以阿拉伯树胶和麦芽糊精为壁材 ,喷雾干燥法制备微胶囊化肉桂醛的工艺条件 .探讨了壁材组成、乳化剂用量、固形物质量分数、芯壁比、进风温度、进料速度、喷射压力等对微胶囊化效果的影响 .经过正交试验 ,确定了最佳工艺条件 .实验结果表明 ,阿拉伯胶和麦芽糊精的最佳质量配比为 1∶1,蒸馏单甘酯的用量为 0 .4 g/dL ,固形物质量分数为 4 0 % ,芯材与壁材的配比为 1mL∶10 g ,肉桂醛微胶囊化的最佳喷雾干燥条件为进风温度 2 2 5℃ ,进料流量 2 10mL/h ,喷射压力0 .18MPa .实验还表明 ,肉桂醛微胶囊产品有一定的缓释抑菌效果 .     

喷雾干燥法制备无花果微胶囊的研究

以阿拉伯胶和麦芽糊精为壁材,以无花果的乙醇提取物为芯材,用喷雾干燥法制取无花果微胶囊粉。通过正交试验分析,确定了最佳生产工艺条件:芯材与壁材的比例为1:4,阿拉伯胶与麦芽糊精的比例为1:1,固形物浓度为30%,乳化剂用量为0.3%,30 MPa均质2遍,进风温度为200℃,出风温度为81℃。生产出的微胶囊无花果粉色泽、溶解性好,水、表面油含量低,无甚粘壁现象,适合于工业化生产。     

微胶囊型天然VE的研究

研究了喷雾干燥法制造微胶囊型VE粉末的微胶囊化工艺及技术.结果表明制造微胶囊型天然VE的壁材及其最佳组合为阿拉伯胶糊精玉米糖浆=22.5%25.O%52.5%,心材与壁材的适宜比例为65,最佳均质压力为30MPa,最佳喷雾干燥造粒工艺条件为进料温度60℃、进料流量150mL/min、进风温度195℃、出风温度70℃.     

苦荞黄酮微胶囊的制备

采用喷雾干燥技术,以阿拉伯胶、β-环状糊精、明胶等为壁材,对苦荞黄酮进行微胶囊化.结果表明:选阿拉伯胶、β-环状糊精(1:1)、明胶(1%)、单甘酯(0.3%)作为苦荞黄酮微胶囊的壁材,可以达到较好的微胶囊效果,并确定芯材与壁材最佳配比为0.1g/g;最佳喷雾干燥工艺条件为:进料固形物浓度为20%,最佳进风温度为180℃,均质压力为30 MPa,产品微胶囊得率及微胶囊化率均可达90%以上.     

黑果腺肋花楸花色苷微胶囊化的研究

研究黑果腺肋花楸花色苷微胶囊化,增加其稳定性,提高附加值。采用喷雾干燥法制备花色苷微胶囊,以包埋率为指标,采用正交试验优化花色苷微胶囊工艺条件,利用高效液相色谱测花色苷含量。结果表明,最佳工艺条件为:壁材(阿拉伯胶与麦芽糊精)质量比2∶3、芯壁质量比2∶8、入口温度120℃、进料量15 mL/min。花色苷微胶囊化后稳定性明显提高。     

二次通用旋转组合设计法优化八角油树脂微胶囊化工艺

采用二次通用旋转组合设计法优化八角油树脂微胶囊化工艺条件,探讨了麦芽糊精、大豆蛋白、八角油树脂、喷雾干燥进风温度等条件对微胶囊的产率和包埋率的影响.结果表明:麦芽糊精20%、大豆蛋白7.5%、八角油树脂5%、喷雾干燥进风温度180℃.此条件所得微胶囊化八角油树脂,气味纯正,呈浅黄色,颗粒细腻,均匀,溶解时间58 S,水分含量2.53%,包埋率为96.7%,微胶囊化效率高达97.3%.     

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.     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.