大豆低聚糖在主食面包中的应用

采用单因素试验设计研究国产大豆低聚糖在主食面包中的应用。主食面包中添加大豆低聚糖能延长面包老化现象,延长货架期达到2～3d,大豆低聚糖保存97.8%以上,主食面包含蔗糖量6%(以面粉计),加入大豆低聚糖量为5.14%以下。      

异麦芽低聚糖面包的研制

通过探讨添加异麦芽低聚糖对面粉粉质、面包焙烤品质以及面包贮存过程中老化程度的影响,以期制作高质量的异麦芽低聚糖面包。试验结果表明,异麦芽低聚糖可改善面团的流变特性,面粉吸水率下降,面团的形成时间、稳定时间延长,面团弹性增加,但面团的延伸性在添加量0%~20%时逐渐增大,超过20%时有所减弱,添加异麦芽低聚糖可有效降低失水率,改善面包的硬度,延长其货架期。在本试验条件下,异麦芽低聚糖的添加量以不超过20%为宜。     

荞麦大豆面包的研制

荞麦富含黄酮类化合物、活性蛋白质等成分,大豆不仅蛋白质含量高,而且是全价的,其中的大豆异黄酮、大豆低聚糖等更具特殊功效。以荞麦粉、大豆粉、面包改良剂为主要添加成分,研制荞麦大豆面包,通过正交试验,确定了三者的最佳添加量,即荞麦粉、大豆粉、面包改良剂分别占面粉重的10%、6%、0·8%。     

大豆低聚糖在馒头中的应用

采用单因素试验设计研究国产大豆低聚糖在馒头中的应用，得出大豆低聚糖在馒头中使用时，能使馒头的货架期延长1d，加入量为3%～5%之间，具有保健意义。     

大豆低聚糖在冰淇淋中的应用研究

采用单因素及正交试验设计研究国产大豆低聚糖在冰淇淋中的应用。得出在冰淇淋中大豆低聚糖的添加量在低于4.0%时,不影响冰淇淋的口感和质量,并具有保健意义,大豆低聚糖保留量达到94.7%。     

大豆低聚糖在冰淇淋中的应用研究

采用单因素及正交试验设计研究国产大豆低聚糖在冰淇淋中的应用。得出在冰淇淋中大豆低聚糖的添加量在低于4.0%时,不影响冰淇淋的口感和质量,并具有保健意义,大豆低聚糖保留量达到94.7%。      

添加剂对面包品质的影响及抗老化作用的研究

试验研究了大豆浓缩磷脂、粉末磷脂、单硬脂酸甘油酯及单双硬脂酸甘油酯对面包品质及抗老化效果的影响。结果发现,在添加量为0.2%~1.0%时,4种添加剂对改善面包的感官品质、比容和质构(硬度、黏聚性和咀嚼性)均有一定效果。其中大豆粉末磷脂对面包品质影响最大,当添加0.8%的大豆粉末磷脂时,面包品质最好,抗面包老化效果最明显。试验的研究结果对面包品质的改良、延长面包存贮期具有一定的实际意义。     

大豆低聚糖在酸奶中的应用

采用单因素试验设计研究国产大豆低聚糖在酸奶中的应用 ,得出在酸奶中大豆低聚糖的添加量在2 %～2 5 %之间时 ,不影响酸奶的质量 ,并具有保健意义 ,酸奶在保藏七天时大豆低聚糖损失率仅为9 8%     

模拟移动色谱连续分离大豆低聚糖技术研究

以预处理后的大豆乳清废液为原料,采用模拟移动色谱分离系统对大豆低聚糖进行纯化。以大豆低聚糖纯度和回收率为指标,对进料量、进料流速、解吸流速、循环量流速等技术参数进行优化,结果表明,在进料量15%,进样流速5 m L/min,切换时间720 s,解吸流速10 m L/min,循环量流速13 m L/min条件下,获得的大豆低聚糖纯度为89%,收率在89%以上。     

大豆低聚糖在乳酸菌饮料中的应用研究

采用单因素及正交试验设计研究国产大豆低聚糖在乳酸菌饮料中的应用,得出在乳酸菌饮料中大豆低聚糖的添加量在低于4.0%时,不影响乳酸菌饮料的口感和质量,并具有保健意义,大豆低聚糖损失率低于10.0%。乳酸菌饮料最佳配方为,果汁4.0%、发酵脱脂乳6.0%、蔗糖12.0%、柠檬酸0.20%、大豆低聚糖4.0%、稳定剂(PGA∶CMC=1∶1)0.30%、L-Vc0.05%、香料0.10%、色素适量、水73.35%。     

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.     

Detection of adulteration of locust bean gum with guar gum by capillary electrophoresis and polarized light microscopy

Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH₃CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH₂PO₄-20.6 mM Na₂B₄O₇ buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.