草莓蜂蜜核桃凝固型酸奶的研制

探索凝固型草莓蜂蜜核桃酸奶的最佳工艺条件。以草莓、蜂蜜、核桃、鲜奶等为主要原料,白砂糖、稳定剂为辅料,保加利亚乳杆菌和唾液链球菌为发酵剂制备凝固型酸奶的工艺。通过正交试验确定产品的最佳配方:草莓蜂蜜核桃比例为1∶2∶1,接种量2%,白砂糖6%,发酵时间4 h,发酵温度为42℃。产品酸甜适口,风味独特,营养丰富,具有保健功能。     

南瓜发酵酸奶的工艺研究

以鲜奶和南瓜为主要原料,以保加利亚乳杆菌为发酵菌种,对南瓜发酵酸奶的工艺进行了研究。通过正交实验确定出发酵工艺的各个工艺参数和酸奶的最佳配方,制成一种营养丰富、风味独特并具有保健功效的南瓜酸奶。实验结果表明,该酸奶最佳配方为南瓜浆10%,蔗糖量8%,乳酸菌接种量3%,稳定剂用量0.2%。最佳复合稳定剂为卡拉胶∶海藻酸钠∶CMC-Na=1∶1∶2,发酵温度42℃,发酵时间4.5h。     

枸杞蜂蜜保健酸奶的研制

以枸杞、蜂蜜、鲜牛奶为主要原料,经过乳酸菌发酵,研制出风味独特,酸甜适中的枸杞蜂蜜酸奶。通过单因素和正交试验确定该酸奶的最佳工艺条件为:枸杞汁添加量10%,蜂蜜添加量6%,蔗糖添加量4%,接入3%的发酵剂,罐装后在42℃发酵5 h。在此工艺条件下制得的枸杞蜂蜜酸奶营养丰富、感官品质佳、稳定性好。     

紫薯酸奶的研制

以紫薯制作酸奶,对紫薯酸奶配方和发酵工艺进行了研究,经正交实验确定紫薯酸奶的最佳配方为:6%的紫薯浆、7%的白砂糖、0.1%CMC和0.1%海藻酸钠的复合稳定剂,最佳发酵工艺为:接种量4%、发酵温度41℃、发酵时间5h。不仅丰富了酸奶的品种,且提高酸奶的营养价值。     

刺梨凝固型酸奶的发酵工艺研究

研究了刺梨及蜂蜜制备的凝固型酸奶的发酵工艺,考察刺梨汁添加量、发酵温度、蜂蜜添加量、乳酸菌接种量及发酵时间对刺梨酸奶感官品质的影响。在单因素试验的基础上采用正交试验优化刺梨凝固型酸奶的发酵工艺。结果表明,刺梨凝固型酸奶最佳发酵条件为：刺梨汁添加量30%、蜂蜜添加量10%、乳酸菌接种量0.15%、发酵温度42 ℃和发酵时间9 h。在此条件下,所得刺梨凝固型酸奶感官评分为92.5分,质地均匀、凝结状态良好、口感细腻,且有浓郁的乳香味和刺梨风味。     

绿豆蜂蜜营养保健酸奶的研制

以绿豆、蜂蜜和鲜牛奶为主要原料研制绿豆蜂蜜保健酸奶的最适配方。结果表明,绿豆浆与鲜牛奶以13∶(v/v)的比例混合,加5%的蜂蜜、4%～5%的蔗糖、0.1%的琼脂,按3%的接种量接入保加利亚乳杆菌和嗜热链球菌(1.2∶1),在42℃下发酵3h,可以制得优质绿豆蜂蜜保健酸奶。     

菊花蜂蜜酸奶的研制及发酵特性研究

以菊花、蜂蜜和牛奶为主要原料研制菊花蜂蜜保健酸奶,通过对菊花蜂蜜酸奶发酵特性的研究,发现菊花提取液、蜂蜜对酸奶发酵有显著的抑制作用。结果表明,采用料液比1∶30(质量比),浸提温度90℃,浸提时间0.5 h所得的菊花提取液,酸奶发酵时添加量应小于15%;蜂蜜添加量应小于10%,并且不同品种蜂蜜对酸奶发酵抑制作用不同;DVS菌种加量0.01%(均为质量分数),发酵时间6 h。     

凝固型蜂蜜银耳酸奶的研制

以牛奶、蜂蜜、银耳为主要原料,以感官评定为标准,通过单因素试验、正交试验,研究凝固型蜂蜜银耳酸奶的最优工艺。结果显示,蜂蜜银耳酸奶的最佳配方为银耳浆添加量5%、蜂蜜添加量8%、羧甲基纤维素添加量0.3%,于42℃培养箱中发酵8 h,然后于4℃冰箱中后熟12 h,即可得到口感酸甜,兼具银耳香气和蜂蜜香味的蜂蜜银耳酸奶。     

苦荞茶酸奶的研制

以苦荞茶和鲜牛奶为主要原料,以保加利亚乳杆菌和嗜热链球菌按1∶1为发酵剂,发酵温度为42℃下,对苦荞茶酸奶的加工工艺进行了研究。采用L9(34)正交试验,得出最佳试验工艺为:苦荞茶鲜牛奶比为1∶60;蔗糖添加量为7%;接种量为4%;发酵时间为3 h。以最佳工艺生产的苦荞茶酸奶色、香、味、组织状态等俱佳。     

响应面法优化百香果酸奶的发酵工艺

通过单因素试验、Plackett-Burman实验、最陡爬坡试验和响应面优化法确定百香果酸奶最佳发酵工艺。结果表明:以果汁添加量、白糖添加量和发酵温度为自变量,响应面法优化出百香果酸奶的最佳发酵工艺为白糖添加量7.4%,接种量0.1%,百香果果汁添加量5.5%,发酵温度42.7℃,发酵时间5 h。在此条件下,酸奶感官评分约达到94.33分,与预测值(93.97分)相差较小。百香果酸奶的酸度、乳酸菌数和大肠杆菌数检测结果均符合食品安全国家标准。     

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