糖化酶用量对酱香型白酒杂油醇的影响研究

研究了糖化酶对酱香型白酒发酵中杂油醇的影响,结果表明:酱香型白酒发酵中糖化酶对杂油醇生成量较大的抑制作用,和未添加糖化酶相比,糖化酶添加2×103U/g时,正丁醇、正丙醇、2-丁醇、异戊醇、异丁醇分别降低了57.22%、43.92%、72.38%、44.38%和90.75%,杂油醇总量降低了48.28%,添加糖化酶对控制酱香型白酒发酵产生杂油醇效果明显。     

酱香型白酒发酵过程中异戊醇的控制研究

在单因素试验研究基础,对影响酱香型白酒发酵主要杂油醇成分异戊醇的酵母添加量、糖化酶添加量、蛋白酶添加量、曲粮比例进行了优化研究,结果组合A2B1C2D2条件下(即酵母添用量加量2%,糖化酶用量2×103U/g,蛋白酶添加量20 U/g,曲粮比例1:1。),异戊醇的产量为0.36×10-1g/L,相对于未添加酵母降低89.80%,表明此优化条件对降低酱香型白酒发酵异戊醇含量效果明显,几个影响因素中,酵母添加量影响显著。     

酵母添加量对酱香型白酒中杂油醇影响

杂油醇是白酒中含量较大且对人体有毒害作用,研究不同酵母菌添加量对白酒中杂油醇含量的影响,研究得出:不同酵母添加量对正丁醇、异丁醇、异戊醇及杂油醇总量影响不同,酵母菌添加量1%时,杂醇油的生成量已趋于平缓,且杂油醇生成量较低,和未加酵母菌相比,杂油醇总量降低39.64%。     

桑椹酒酿造过程中高级醇生成的影响因素研究

针对桑椹酒中高级醇含量过高的问题,研究了初始pH值、发酵温度、接种量、SO2添加量、氮源添加量等因素对桑椹酒酿造过程中高级醇生成的影响.试验结果表明:适当增加接种量或降低初始pH值、发酵温度,高级醇生成量明显降低;添加氮源,高级醇生成量增加;在一定范围内,随SO2含量的增加,高级醇生成量增加,当SO2含量达200.00mg/L时,高级醇的生成受到抑制.     

不同加曲量对酱香型白酒中杂油醇影响探讨

杂油醇是白酒中含量较大且对人体有毒害作用,实验研究了不同大曲加量对白酒中杂油醇含量的影响,研究得出,不同大曲加量对正丁醇、异丁醇、异戊醇及杂油醇总量影响不同,曲料比1:1和1:1.3时,杂醇油的生成量已趋于平缓,加曲量来控制杂醇油的生成具有可行性.     

中国清酒中降低高级醇含量的研究

从高级醇生成机理入手,研究了中国清酒发酵过程中减少高级醇生成量的方法和条件.实验结果表明:碳酸氢铵的添加量对高级醇生成的影响非常明显,随着碳酸氢铵添加量的不断增加,高级醇生成量逐步减少,当添加的碳酸氢铵达到一定量时,高级醇含量则不再变化,继续增加添加量则有回升现象.     

巨峰葡萄酒酿造过程中高级醇生成的研究

葡萄酒中的高级醇为酵母代谢过程产物,是葡萄酒中的主要香味物质。不同接种量、添加不同氮源及葡萄汁含氮量都会影响高级醇的生成量。接种量在6×106个m/L时高级醇生成量较小,葡萄汁中酵母浓度过高或过低都会使高级醇生成量增大。葡萄汁中α-氨基氮总量为180～195m g L/时,杂醇油的生成量较低。添加亮氨酸对高级醇生成量影响最为显著,甘氨酸对高级醇生成量基本无影响。(孙悟)     

生物制剂调控浓香型白酒高级醇产量

为了探讨生物制剂对于浓香型白酒高级醇产生的影响,调控高级醇的产量,采用实验室模拟固态发酵的方法,通过添加生物制剂,测定高级醇的产量,利用正交试验、二次多项式逐步回归和响应面分析法,建立生物制剂添加量同白酒中高级醇生成量的关系。结果表明:添加活性干酵母0.8%、糖化酶1 000U/g、α-淀粉酶50U/g时,高级醇总量比空白降低了21.06%。构建的数学模型,可以预测不同干酵母、α-淀粉酶、糖化酶的添加量时高级醇产量,从而达到在既满足浓香型白酒应有风味的同时,又能有效地调控高级醇产量,提高浓香型白酒的品质的目的。     

发酵醪中添加酸性蛋白酶对黄酒稳定性的影响

为提高黄酒的稳定性,在不同发酵阶段加入不同量的酸性蛋白酶,通过对黄酒糖、酒、酸、氨基酸态氮进行检测分析结果表明,它们的生成量与加入蛋白酶的量成正比,对氨基酸态氮的影响最明显。通过冷混浊与强化试验,发现加入10~20 U/g的蛋白酶的黄酒浊度比空白原酒降低了0.3左右,冷混浊的沉淀量比原酒明显减少。这说明发酵时加入蛋白酶能提高黄酒的稳定性。发酵的不同时期加入相同量的酸性蛋白酶对黄酒的理化指标、黄酒稳定性都没有显著的影响,结合实验数据与企业成本两方面考虑,选用15 U/g的酸性蛋白酶最好。     

矿泉水臭氧消毒中溴酸盐的形成与控制

为控制矿泉水中溴酸盐含量,采用改变臭氧浓度的方法,对添加溴离子的矿泉水、超纯水和自来水分别进行臭氧氧化5 min,观察臭氧氧化过程中臭氧、溴离子以及水质对溴酸盐生成的影响;同时利用向自来水中添加一定浓度溴离子的方法,研究CT值(Ozone Concentration×Contact Time,CT)对溴酸盐生成的影响。结果表明,随着臭氧浓度和溴离子浓度的增加,溴酸盐生成量增加。当臭氧质量浓度≥0.4 mg/L,添加相同浓度的溴离子时,矿泉水中生成的溴酸盐量大于自来水和超纯水中溴酸盐量。矿泉水不同,添加相同浓度的溴离子,生成的溴酸盐量也不同,但当臭氧质量浓度≥0.4 mg/L时,溴酸盐量均大于10μg/L。CT值增大导致溴酸盐生成量大幅增加。因此,可以通过降低臭氧浓度和溴离子浓度的方法,减少臭氧消毒中溴酸盐的生成量。     

外源抗氧化剂对荔枝酒发酵的影响研究

为了解决过量二氧化硫影响果酒品质的问题,探索二氧化硫的取代物,考察了添加二氧化硫、抗坏血酸、异抗坏血酸、谷胱甘肽和乙二胺四乙酸（EDTA）对荔枝酒中多酚氧化酶（PPO）、过氧化物酶（POD）、总糖、总酸、酒精度、杂醇油和总酯的影响。结果显示,添加抗氧化剂有利于抑制酶活、促进香气物质的生成。在抗氧化剂添加量为250 mg/L时,添加异抗坏血酸比添加SO2的酒样中PPO酶活、POD酶活、总糖分别降低了70.0%、66.7%、79.4%,而酒精度、杂醇油、总酯分别提高了3.8%、16.5%、61.4%;添加EDTA比添加SO2的酒样中PPO酶活、POD酶活、总糖分别降低了60.0%、58.3%、75.0%,而酒精度、杂醇油、总酯分别提高了1.9%、10.8%、57.1%。研究表明,添加异抗坏血酸或乙二胺四乙酸可以部分的取代二氧化硫,有利于提升荔枝酒的品质。     

气相色谱法测定清爽型黄酒中的乙醛和杂醇油含量

乙醛和杂醇油是饮用黄酒引起上头的主要因素。建立了外标法毛细管气相色谱法测定清爽型黄酒中乙醛和杂醇油的方法,PEG-20色谱柱,氮气为载气,FID检测器,外标法定量。结果清爽型黄酒样品中乙醛含量达到40.5mg/L,杂醇油达到38.3mg/100mL,样品加标回收率在91.7%～98.5%之间,相关系数大于0.9973,相对标准偏差为0.83%～3.8%。     

Effect of fusel oil addition on volatile compounds in papaya wine fermented with Williopsis saturnus var. mrakii NCYC 2251

The impact of fusel oil addition on volatile compounds formation in papaya wine fermented with yeast Williopsis saturnus var. mrakii NCYC2251 was studied with a view to enhancing papaya wine aroma production. Time-course papaya juice fermentations were carried out using W. saturnus var. mrakii NCYC2251 with fusel oil added (0, 0.1 and 0.5% v/v). Fermentation characteristics in terms of yeast growth, Brix and pH changes were similar for all fermentations except for those added with 0.5% (v/v) fusel oil. The addition of 0.5% (v/v) fusel oil inhibited yeast growth. A wide range of volatile compounds were produced during fermentation including acids, alcohols, esters and aldehydes with esters being the most abundant volatile compounds produced. The addition of 0.1% (v/v) fusel oil reduced the production of undesirable volatiles such as ethyl acetate and acetic acid, while increasing the desirable volatiles production such as ethanol and acetate esters. This study suggests that papaya juice fermentation with W. saturnus var mrakii NCYC 2251 together with a low concentration of added fusel oil can be another means of modulating papaya wine aroma compound formation.     

葡萄酒中杂醇油分析

对葡萄酒中杂醇油的产生原因进行了分析;提出了降低葡萄酒中杂醇油含量的相应措施;比较分析了测定葡萄酒中杂醇油常用的几种方法。     

桑椹酒质量安全控制技术研究进展

桑椹酒酿造技术难度高,主要是挥发酸、甲醇、杂醇油含量的控制以及风味、色泽、澄清度等品质的提升。该文通过原料品质、酵母、工艺、原酒存储等方面综合调控从而抑制挥发酸含量的升高;通过原料采收管理、去渣发酵、酵母菌选用、控温发酵等措施控制甲醇含量升高;通过无机氮源和低产杂醇油酵母的应用,以及低温发酵等技术将杂醇油含量控制在较低水平;通过抗病品种选育、合理防治避免桑椹酒农药残留较高。该综述对现阶段桑椹酒酿造关键技术研究进行总结,探讨桑椹酒发酵过程中挥发酸、甲醇、杂醇油含量、农药残留的影响因素及控制措施,为桑椹酒产业化生产提供参考。     

REDUCTION OF HIGHER ALCOHOLS BY FERMENTATION WITH A LEUCINE-AUXOTROPHIC MUTANT OF WINE YEAST

Several auxotrophic mutants requiring branched chain amino acids (valine, leucine, or isoleucine) were isolated in a strain of Montrachet wine yeast. They were tested for their ability to produce lowered amounts of higher alcohols (‘fusel oil’: isobutyl, active amyl, and isoamyl alcohols) in grape juice fermentations. One strain which required leucine was especially good in this respect. This mutation is recessive and is the result of a deficiency for the enzyme α-isopropylamate dehydratase. In trial fermentations with this mutant, the resulting wines contained up to 20% less total fusel oil and 50% less isoamyl alcohol compared to the parent Montrachet strain. An experienced taste panel did not discern any gross degradation of taste quality in wine made with the mutant strain compared to that made with the parent strain. The mutant strain could be of commercial importance in preparation of distilling material for alcoholic beverages since the reduced fusel oil content would not require any special distillation procedures which are normally used to avoid the unpleasant flavour associated with concentrated higher alcohols. Reduction of the isoamyl alcohol content is particularly significant since this fusel oil component is usually present in the highest amount.     

荔枝酒中杂醇油含量的测定

采用气相色谱法,以叔戊醇为内标物,对荔枝酒中杂醇油的含量进行了测定,并与分光光度法进行了比较分析。实验结果表明,气相色谱法不仅可以检测出荔枝酒杂醇油总量,还能检测出杂醇油组分的含量;荔枝酒中,杂醇油含量较多的成分分别为异戊醇、异丁醇和正丙醇,荔枝干酒中三者含量之和占到杂醇油总量的99.0%;分光光度法是以异丁醇和异戊醇的含量作为杂醇油总量,该法无法检测到荔枝酒中正丙醇的含量,不能准确测定荔枝酒中杂醇油含量,气相色谱法具有简单、快速、精密度高等特点,较分光光度法更适合于荔枝酒中杂醇油含量的测定。     

酸性蛋白酶对黄酒常规质量指标的影响

随着酿酒工业的发展,酶制剂在黄酒酿造中的应用也越来越广泛。主要对酸性蛋白酶在黄酒生产中对常规质量指标的影响进行了研究。研究表明,添加不同量的酸性蛋白酶对黄酒2d内的酒精度影响较大;可以使总糖含量略微增加;易引起黄酒的酸败,并且与添加量成正比;当酸性蛋白酶添加量为50U/g时黄酒中的氨基态氮含量能达到一级黄酒的级别。旨在为进一步研究酸性蛋白酶在黄酒生产的应用提供依据。     

Kaffircorn malting and brewing studies XV.—The fusel oils of kaffir beer

A method for determining the fusel oil content of kaffir beer, based on the A.O.A.C. method for alcoholic beverages, was developed. The average fusel oil content of kaffer beer is high, 227 ppm in comparison with European type beer (average 110 ppm). The increase of fusel oil and ethanol content with time (0-72 h after seeding) was studied. Abnormally heavy yeast seedings reduced the fusel oil content from 290 to 190 ppm without affecting alcohol production. Combination of heavy seeding and ammonium phosphate reduced the fusel oil to 90 ppm, the level found in many European type beers. The ethanol content was reduced from 3·5 to 2·5% (v/v). Fusel oil produced relative to the amount of ethanol formed revealed that heavy seeding, with and without the addition of ammonium salts, reduced the amount of fusel oil formation by 2/3 and 1/3 respectively.