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1.
针对野生红心果果酒的发酵,以发酵温度、二氧化硫添加量和酵母菌接种量作为发酵过程中酒精度的影响因素,利用响应面分析法(Response Surface Methodology)对野生红心果果酒发酵工艺进行优化。在单因素试验基础上选取试验因素与水平,根据Box-Benhnken的实验设计原理,采用三因素三水平的响应面分析法。结果表明,野生红心果果酒发酵工艺的最佳参数为:二氧化硫添加量A为51.3 mg/kg,酵母菌接种量B为5.33%,发酵温度C为24.98℃。在此发酵工艺条件下野生红心果果酒酒精度的理论值为9.58%。  相似文献   

2.
以霞多丽和玫瑰香为原料,通过优化和添加两种皂土处理方式,研究皂土对酒精发酵和葡萄酒质量的影响.结果表明:添加处理可增加葡萄汁中不溶性固形物含量,对最大发酵速率和总发酵时间及葡萄酒组分无明显影响;优化处理可提高葡萄汁的澄清度,降低发酵速率,延长总发酵时间,使葡萄酒的残糖含量较高.无论是添加处理还是优化处理均对葡萄汁的氨基氮含量无明显影响,因此在优化葡萄汁中添加氮素营养不能扭转发酵缓慢现象.  相似文献   

3.
对葡萄汁在发酵过程中,影响甘油生成量的六个主要因素:酵母菌株,葡萄汁含糖量、二氧化硫的添加量、发酵温度、葡萄原料所寄生的灰葡萄孢霉、酒石酸含量,进行了叙述。  相似文献   

4.
5 自然发酵与纯粹发酵传统的葡萄酒酿造,都是采用自然发酵的工艺。所谓自然发酵葡萄酒,就是葡萄破碎入罐以后,不人为地添加任何酵母菌种,靠葡萄本身携带的自然界的酵母菌,在葡萄浆里或在分离后的葡萄汁里自发地繁殖,引起发酵,最终发酵成葡萄酒。前面已经讲过,从自然界带入葡萄发酵醪里的酵母及其他的微生物是各种各样的。其中绝大多数是野生的尖端酵母。野生的葡萄酒酵母,在发酵起始以前或起始阶段占的比例极小。由于葡萄汁本身酸度较高,pH值较低,所以大部分的细菌等微生物,无法适应这种环境,难以繁殖。野生的尖端酵母,也…  相似文献   

5.
葡萄酒是葡萄汁经过酵母发酵得到的产物。葡萄果实上带有大量的酵母菌,所以葡萄成熟后,经过破碎就会自然发酵。葡萄汁中的糖价在酵母菌的作用下生成酒精,二氧化碳和其他发酵副产物,形成葡萄酒特有的风格。葡萄汁能够进行自然发酵这一现象几千年前就为人类发现,至今许多国家葡萄酒生产仍采用这一工艺。随着葡萄酒酿造技术  相似文献   

6.
为筛选出发酵玫瑰香葡萄酒效果最佳的粟酒裂殖酵母菌株,该试验首先通过不同发酵温度(23、25、28℃)和不同接菌量(1×106、5×106、1×107CFU/mL)对玫瑰香葡萄进行发酵,优选出适用于粟酒裂殖酵母的最适发酵温度和最适接菌量。然后利用前期根据发酵动力学试验筛选出的16株粟酒裂殖酵母对玫瑰香葡萄进行单独发酵。结果表明:适合粟酒裂殖酵母的发酵温度为25℃,接菌量为5×106CFU/mL。相较于其他发酵菌株,筛选出的粟酒裂殖酵母Sp-410单独发酵玫瑰香葡萄酒的苹果酸的降解率(97.98%)和色度值(1.26)最高,乙酸含量(0.18 g/L)和乙醛含量(48.46 mg/L)最低,因此,优选出的粟酒裂殖酵母菌Sp-410为酿造优质玫瑰香葡萄酒的优良菌种。  相似文献   

7.
喜欢喝葡萄酒的人发现,欧美的葡萄酒标签中的成分栏内几乎都含二氧化硫。这个常常跟酸雨、空气污染物相关联的"有毒有害的化学物质"怎么会堂而皇之地出现在了"典雅"的葡萄酒中?二氧化硫,葡萄酒不得不用葡萄酒是由葡萄汁发酵而成,葡萄汁中含有大量的糖,在发酵过程中酵母菌会把它们转化成酒精。所以,发酵越充分,转化就越完全,最后的成品中酒精含量就越高,糖含  相似文献   

8.
张春娅  张军  王树生 《酿酒》2006,33(6):80-81
通过采用冷冻法浓缩玫瑰香葡萄汁,然后进行发酵,生产出了一款优质的甜白型葡萄酒。  相似文献   

9.
以白葡萄汁为原料,采用植物乳杆菌与酵母菌复配发酵,采用3因素3水平正交试验,以风味评价为指标,确定了发酵白葡萄汁原液的最佳工艺。其最佳工艺参数为:植物乳杆菌:酵母菌=5∶1,接种量4‰,发酵温度37℃,发酵时间10h,冷藏温度4℃,冷藏时间18h。利用发酵白葡萄汁原液进行发酵果汁成品的探索,果汁最佳配方为:发酵白葡萄汁原液25%、脱脂乳粉1%、蔗糖6%、果胶0.2%、大豆多糖0.1%。  相似文献   

10.
山葡萄酒苹果酸—乳酸发酵工艺优化   总被引:1,自引:0,他引:1  
为改善山葡萄酒的风味,对其苹果酸—乳酸发酵工艺条件进行优化。结果表明,山葡萄酒苹果酸—乳酸发酵的最佳工艺条件:初始pH 3.00,温度20℃,接种量4mL/100mL,含糖量10.7g/L。在最佳工艺条件下对东北山葡萄酒进行二次发酵,制品pH值相对于原发酵葡萄汁升高0.19±0.05,总酸度(以苹果酸计)相对于原发酵葡萄汁降低(2.67±0.10)g/L,缓解了山葡萄原酒的酸涩味,增加了适口性。  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   

15.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
19.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

20.
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.  相似文献   

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