利用植酸酶降低玉米原料酒精生产成本的研究

植酸酶不仅应用于饲料工业,还可应用于玉米酒精生产中,它能分解玉米原料中的植酸磷,释放出无机磷,促进酵母发育及代谢,提高酒精产量及保护环境。以玉米粉为原料,安琪酵母为发酵菌种,探讨了在玉米原料酒精中添加植酸酶对酒精发酵的影响。结果表明,在酒精发酵开始时添加5U/g原料的植酸酶,与对照相比,酒度增加了0.8%(v/v),发酵醪中磷含量提高了7.2%,原料出酒率提高了1.6%。通过植酸酶在酒精生产中的应用研究,对降低酒精的生产成本必将起到推动作用。     

植酸酶在玉米原料酒精生产中的应用

植酸酶分解玉米原料中的植酸磷，释放出无机磷，促进酵母发育及代谢。实验结果表明，发酵时添加植酸酶，酒精含量平均提高0．8％(v／v)，原料出酒率平均提高1．6％，即生产1t酒精可节省140kg玉米，效益非常可观。     

燃料酒精制备研究

该研究在传统发酵制备燃料酒精基础上,根据原料成分与影响发酵因素,在实验中添加果胶酶和植酸酶;结果表明:添加果胶酶6 U／g原料,作用时间30 min,植酸酶7 U／g原料时,使酒精度提高1．6％(v／v),原料出酒率提高3．9％,降低生产成本4．3％,同时缩短发酵时间8hr,从而有效降低生产燃料酒精成本;经济效益分析表明:这是一种切实可行燃料酒精制备工艺。     

安琪耐高温酿酒高活性干酵母在酒精浓醪发酵中的应用

使用安琪耐高温酿酒高活性于酵母，以玉米为原料生产酒精，通过在发酵过程中添加复合酶，采用边糖化边发酵工艺，从三角瓶小试，到5t罐中试，取得了一定效果，残还原糖为0．21％，酒分达到13．6％(v／v)。同时证明了在稀醪条件下适当提高发酵温度可加快酵母的产酒，但在浓醪情况下，提高温度会增加乙醇对酵母的毒性，导致出酒率下降。     

应用浓醪发酵技术推动酒精行业科学发展

高浓度酒精发酵始于20世纪70年代,主要以可再生资源粮食或植物纤维为原料,采用连续发酵,最终酒精浓度可达16％(v／v)左右,实验室小麦粉高浓发酵可达21％(v／v),淀粉利用率达90％以上,发酵时间在50～70h。在蒸煮工艺方面对低温蒸煮、中温蒸煮及生料发酵作了探索。浓醪发酵的料水比为1：2．8～3．2。安琪酵母股份有限公司研究开发的安琪超级耐高温酿酒高活性干酵母已形成生产力,并投入大生产使用,其发酵结束时醪液的酒精浓度可达到14％～17％(v／v)。国内外在实验室筛选分离的酒精酵母,有的产酒精浓度可达20％(v／v)左右,但大都尚未形成生产力。酒精浓醪发酵技术是一个方向,对生产企业提高效益,节约能源,保护环境将有积极的促进作用。应以科学发展观为指导,大胆采用酒精浓醪发酵技术,大力推进酒精行业的科技进步,促进酒精产业的健康发展。     

玉米酒精浓醪发酵工艺研究

采用安琪耐高温酒精活性干酵母，以玉米为原料进行浓醪发酵最适工艺条件的研究，结果表明，双酶法液化法，添加180u／g糖化酶，pH4．5-5．0，酵母接种量0．15％，适当添加无机盐和营养剂，发酵70h，最终达到发酵酒度14．7％(v／v)，残糖0．92％，残还原糖0．2％，淀粉利用率84．9％的良好效果。     

酸性蛋白酶用于酒精浓醪发酵的研究

在料水比为１∶２．８～３．２的酒精浓醪发酵中,添加适量的酸性蛋白酶,可缩短发酵周期至４８ｈ,其原料出酒率为３２．５１％,比对照提高约１．０４％,吨酒精可节省玉米用量１０２ｋｇ,成本降低约９１．８元,经济效益十分显著     

酒精发酵中应用酸性蛋白酶的研究

对酸性蛋白酶在酒精发酵中的应用进行了研究。添加酸性蛋白酶有利于原料中蛋白质的水解，增加醪液中酵母可吸收性氮，促进酵母菌生长繁殖，提高酒精发酵速率。而且，a-氨基氮的增加，减轻了酵母菌细胞氨基酸合成代谢的负荷，使底物（葡萄糖）更多地转向发酵生成乙醇，提高原料出酒率。接种酵母后，在醪液中添加0．01％的酸性蛋白酶，发酵时间由原来的52h缩短到32h，发酵成熟醪酒精含量为10．2％（V）。着延长发酵时间至44h，则发酵成熟醪中酒精含量由原来的9．8％（V）增加到10．7％（V），并对添加酸性蛋白酶和（NH4）2SO4的发酵结果进行了比较，认为酸性蛋白酶是实现高效率酒精发酵的优选促进剂。     

"克菌灵"在玉米酒精生产中的应用研究

在玉米酒精生产中添加克菌灵可抑制杂菌生长。在发酵前期加入,最佳使用量为6mg／L,酸度可降低0．2,酒精度可提高0．4％（v／v）,原料出酒率提高0．9％。     

玉米原料纳米化处理对酒精发酵的影响

对经纳米化处理的玉米原料和未经纳米化处理的玉米原料进行了发酵对比研究。结果表明，在糖化条件及发酵条件相同的情况下，原料不经纳米化处理，其酒精浓度为13．2％(v/v)；而原料先纳米化处理后糖化，酒精浓度为14．1％(v/v)，原料先糖化后纳米化处理，酒精浓度为15．1％(v/v)，分别比未经纳米化处理的酒精产量提高了6．81％和14.39％。     

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