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1.
外加酶法酿制低糖啤酒糖化工艺的研究   总被引:1,自引:0,他引:1  
以普鲁兰酶Promozyme120L为重点,综合分析了外加酶糖化过程中影响麦汁总还原糖量和糖组成的各种因素,如各酶制剂的用量、糖化温度、料水比、物料比及各因素之间的相互作用等,确定了一套最优的糖化工艺方案。所得麦芽汁浸出率高、色度浅、粘度低、还原糖含量高;经过高效液相色谱分析(HPLC)表明,其糖组成合理;经过十天的发酵,发酵度达82.2%,酒精分为6.455%(W/W)。  相似文献   

2.
以仙人掌、绿豆为原料,研究了发酵型仙人掌绿豆醋酸饮料的工艺,讨论了绿豆制汁时液化、糖化的最佳参数,及仙人掌的护色夺件、仙人掌绿豆饮料的产品定型等。  相似文献   

3.
在麦汁主要成分给定的情况下,水质、外加酸以及麦汁煮沸时间是影响麦汁缓冲容量的重要因素,缓冲容量愈大,高级醇含量愈高。结果表明:pH5.0的酸水糖化效果较好;较大缓冲容量的水质有利于麦芽的糖化;盐酸、磷酸和乳酸的使用能提高麦汁的缓冲容量;充分的煮沸可使其缓冲容量降低30%以上;麦汁的缓冲容量对啤酒中高级醇浓度有较大的影响,可以通过控制麦汁的缓冲容量来实现对发酵过程pH的控制。  相似文献   

4.
肖亚新 《酿酒》1998,(6):39-40
啤酒糖化麦汁收得率是指每100公斤原料经糖化生产后的定型麦汁中,获得浸出物的百分数。它直接关系到最终麦汁的产量,关系到啤酒的粮耗成本。管理先进的企业,糖化收得率达到76%以上,吨酒粮耗在170公斤以下;管理差的企业,糖化收得率在74%以下,吨酒粮耗在...  相似文献   

5.
"米邦塔"仙人掌汁的营养特性及酶法澄清研究   总被引:5,自引:0,他引:5  
对仙人掌汁营养成分及果胶酶法澄清仙人掌汁的工艺条件进行研究。结果表明,仙人掌汁中高钾低钠,钾钠比1314:1,SOD活力103.97U/mL,多糖1.96%,由成分分析可知,仙人掌汁是一种集多功能成分于一身的营养物质;采用响应面分析确定果胶酶澄清汁液时的最佳酶解工艺备件:酶加量0.14g/L、酶解时间1.8h、CaCl2添加量0.215g/L、酶解温度50℃、反应液pH4.5,所得汁的透光率达到94.2%。  相似文献   

6.
啤酒厂糖化工序的热能消耗约占整个厂热能消耗的50%。本文通过一个典型的60千升/批次麦汁糖化设备为例,分析糖化工序的蒸汽消耗状况。一、工艺条件糖化设备采用六器组,8批次/天~10批次/天;麦汁浓度12°P;大米、麦芽采用湿粉碎;糖化、糊化采用底部进料;麦汁煮沸采用低压动态工艺;回收煮沸产生的二次蒸汽,用以预热从暂存槽到煮沸锅的麦汁。  相似文献   

7.
沙棘果粉碎后分离出的果汁需加果胶酶进行澄清,澄清温度20-25℃,pH4.2~4.5,果胶酶加量为0.3%~0.4%。麦汁冷却后,满罐时将沙棘汁定量泵入发酵罐,添加酵母进行发酵。生产中应注意:①沙棘汁含糖量较高,实际生产中原麦汁浓度可略低一些;②沙棘加工过程应切实做好防氧化并保持沙棘果汁无菌状态;③沙棘汁中果胶物质含量较高,若处理不好将对成品酒非生物稳定性产生很大影响;④沙棘果汁添加量应根据有效量及啤酒品质来确定。(丹妮)  相似文献   

8.
啤酒酿造过程中有机酸的研究   总被引:3,自引:0,他引:3  
向阳  李崎  顾国贤 《酿酒科技》2005,(10):51-54,57
研究不同的糖化工艺对麦汁中有机酸含量的影响。通过改变原料状况(不同的辅料比、粉碎度)、糖化水pH、糖化温度、糖化时间等工艺参数,发现麦汁中的有机酸主要来自麦芽呼吸产生的酸,糖化过程中的酶解作用几乎不产生有机酸,且麦芽原始酸和总有机酸含量之间具有较好的线性关系(R^2=0.943)。麦汁煮沸时添加酒花和钙离子,可以使麦汁中的有机酸含量下降10%。  相似文献   

9.
过滤槽法过滤麦汁,可影响麦汁的糖化继续;带入氧影响麦汁质量;洗糟也影响麦汁质量。过滤槽法过滤麦汁的操作要点有:控制氧的带入;提高麦汁的清亮度;提高过滤速度,缩短过滤时间;过滤过程中加强对麦汁质量参数的检查。(孙悟)  相似文献   

10.
麦汁为啤酒的主要原料,麦汁的制备决定了啤酒的种类和质量,并直接影响到啤酒生产工艺与成品质量,因此在啤酒生产过程中需要不断优化麦汁制备工艺,形成优良的麦汁色度。麦汁的制备工艺主要包括麦芽制备、麦芽粉碎、糖化、麦汁煮沸沉淀、麦汁过滤与主发酵等步骤,其中糖化工艺会对啤酒麦汁的色度与品质造成影响。因此,需控制好麦芽质量及其粉碎度、糖化温度、淀粉酶pH值、糖化醪浓度等因素,并进一步优化糖化工艺参数,为呈现更好的啤酒麦汁色度奠定坚实的基础。基于此,本文研究糖化工艺对啤酒麦汁色度的影响,并提出啤酒麦汁制备中糖化工艺的优化措施,以提高啤酒麦汁的色度,促进啤酒酿造工艺的优化,推动啤酒行业的高质量发展。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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17.
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.  相似文献   

18.
<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  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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