低糖南瓜果脯加工工艺研究

研究生产低糖南瓜果脯的生产工艺，并对影响低糖南瓜果脯品质的硬化、渗透脱水、真空渗糖和干燥等关键加工工序进行探讨。试验结果表明：采用0．2％的CaCl，对原料进行硬化；30％的白砂糖、1％的食盐混合液渗透脱水4h，糖制过程采用40％白砂糖、2．5％葡萄糖、0．6％CMC—Na混合液一次真空渗糖40min（0．09MPa），采用先50℃，1h再变温到70℃继续干燥16h的变温非鼓风干燥工艺．可生产出品质优良的低糖南瓜果脯。     

低糖无硫草莓果脯生产工艺技术的研究

对影响低糖无硫草莓果脯品质的烫漂、硬化、护色、渗糖、浸糖、干燥等关键工艺技术进行了研究。结果表明:最佳烫漂时间为2min,温度为90℃;护色剂采用1%的柠檬酸和0.2%的VC混合液,时间为15～20min;采用4%的δ-葡萄糖酸内酯硬化4h;糖液配制用50%的淀粉糖浆取代50%的蔗糖,同时添加0.5%的果胶,3%的磷酸钠和氯化钾混合液;用50%的糖液常压渗糖20min,常温浸糖9h;干燥在65℃下先烘干4h,翻转过来整形后再干燥4h;为最佳工艺制得的草莓果脯品质最好。     

低糖雪莲薯果脯真空渗糖工艺条件的优化

研究低糖雪莲薯果脯的加工工艺条件,对护色、漂烫和硬化等渗糖前预处理过程进行研究,得出最佳条件:用0.4%浓度的柠檬酸溶液对原料护色,沸水漂烫10min,0.5%浓度氯化钙溶液对原料进行硬化2 h.采用真空渗糖的方法对原料糖渍处理,并对真空渗糖温度、渗糖时间、柠檬酸用量和糖液浓度等因素设计正交试验,得出最佳工艺条件:温度35℃、时间120min、柠檬酸0.20%及蔗糖45%.     

低糖地参果脯的微波渗糖工艺

以地参为原材料,采用单因素试验研究烫漂时间、总糖醇添加量、微波渗糖功率和时间、干燥时间对低糖地参果脯的影响;以总糖醇添加量、微波渗糖功率和微波时间为试验因素,以含糖量、感官评价为指标,设计L₉(3⁴)正交试验,以优化低糖地参果脯的加工工艺。结果表明,低糖地参果脯的最佳配方工艺为烫漂时间2 min,总糖添加量35%,微波渗糖功率为40%,微波渗糖时间为40 min,干燥时间6 h,此条件下制得的果脯品质最佳。     

利用芒果落果加工低糖果脯的研究

初步探讨了以芒果落果制作低糖果脯的加工工艺。结果表明：采用3次真空渗糖工艺，糖液浓度分别为35％、45％、55％，渗糖时间均为30min，并在糖液中添加1．0％的柠檬酸和0．5％的明胶，可得到品质风味优良的低糖芒果果脯。     

利用莲雾落果加工低糖果脯

以莲雾落果为原料,探索低糖莲雾果脯的加工工艺,并重点研究护色、硬化、烫漂、渗糖等过程对低糖莲雾果脯品质的影响。结果表明:采用0.15%抗坏血酸进行护色,2%的氯化钙进行硬化,放入90℃热水中烫漂15min;在含量为25%蔗糖,10%葡萄糖,0.3%柠檬酸,0.6%明胶的溶液中,0.085MPa真空环境下渗糖15min,常压浸糖5h;将充分浸糖后的莲雾放入干燥箱内[前期50℃～60℃(2h),后期60℃～80℃(约2h)]至水分含量约20%左右。制得的低糖莲雾果脯酸甜适口、饱满透明、色泽自然、质量优良,果脯风味最佳。     

低糖沙子空心李果脯的研制

以沙子空心李为主要原料,采用常温渗糖加工低糖沙子空心李果脯,探讨漂烫温度、木糖醇添加量、渗糖时间、干燥时间对低糖沙子空心李果脯感官品质的影响,通过单因素试验和正交试验优化得到低糖沙子空心李果脯的最佳工艺参数。结果表明,低糖沙子空心李果脯的最佳配方工艺为漂烫温度80℃,木糖醇添加量40%,渗糖时间12 h,干燥时间40 h,该条件下其组织饱满、硬度适宜、表面光泽、无返砂现象、酸甜可口。     

低糖杏脯制作工艺研究

以鲜杏为原料,研究低糖杏脯的制作工艺。以制品的色泽、饱满度、含糖量、剪切力为评价指标,研究漂烫时间、真空渗糖工艺参数、填充浓度、护色剂种类、糖液浓度等因素对制品品质的影响。结果表明,杏坯用0.4%CaCl2溶液硬化4h、漂烫3min;采用真空二次渗糖工艺,添加填充剂3%、VC0.2%,一次糖液浓度为30%,二次糖液浓度为45%,糖液温度60℃,真空度0.07MPa,真空保持时间20min;浸糖24h,60℃恒温干燥10h,所得杏脯湿基含糖量为41%—43%,水分含量18%—20%,制品品质优良。     

超声波法加工低糖保健型宣木瓜果脯工艺的研究

以宣木瓜鲜果为原料,益寿糖替代传统的蔗糖,并利用超声波渍糖技术,加工低糖保健型宣木瓜果脯。实验采用对比法研究了鲜果片的漂烫工艺,并对护色、去涩、硬化以及超声波渗糖等关键加工工艺进行了优化。结果表明,鲜果片100℃烫漂处理4min后立即冷却,用2.5%NaCl、0.5%柠檬酸、4%δ-葡萄糖酸内酯配制的混合溶液常温浸泡12h进行护色、去涩、硬化处理,采用水料比为4:1的清水浸泡果片脱盐120min,再在300W的超声波45℃条件下,45%益寿糖液渗糖5h,所得果脯感官评价最好。     

低糖雪莲果果脯的研制

以雪莲果为原料,对其果脯加工中的硬化、护色、渗糖、干燥等工艺条件进行了实验研究.结果表明,低糖雪莲果果脯加工的最佳工艺条件为:热烫90℃、3min;用3%葡萄糖酸内酯、0.15%的抗坏血酸溶液硬化护色6h;填充剂选择0.4%的低甲氧基果胶+0.2%的魔芋精粉;渗糖工艺采用真空渗糖.糖液浓度为50%.真空度0.075MPa,保持2h;于55℃下干燥24h,在此工艺条件下生产出了色、香、味俱佳,形态饱满,透明的低糖雪莲果果脯.     

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