总状毛霉与鲁氏酵母耦合发酵 对豆粕营养和风味的增强效应

本文以总状毛霉为主要菌种,探究发酵对豆粕营养和风味的增强作用以及鲁氏酵母耦合发酵和豆粕原料超声前处理对毛霉发酵豆粕品质的作用。结果表明,总状毛霉发酵能显著提高豆粕中性蛋白酶活力、可溶性蛋白含量、感官品质、总氨基酸和游离氨基酸含量,并有效降低胰蛋白酶抑制剂活力;28 ℃发酵60 h,各发酵豆粕蛋白酶活力和可溶性蛋白含量均达到最大值,与未发酵豆粕相比,总状毛霉发酵豆粕蛋白酶活达到1032.4 U/g,可溶性蛋白、总氨基酸和游离氨基酸含量分别增加3.16倍、13.64%和5.65倍,胰蛋白酶抑制剂活力降低了84.57%。豆粕原料超声前处理和鲁氏酵母耦合发酵均有助于强化毛霉发酵豆粕的品质,其中超声前处理后毛霉和鲁氏酵母耦合发酵豆粕胰蛋白酶抑制剂含量从4375 U/g下降到350 U/g,减少了92%,游离氨基酸含量增加了7.69倍,总氨基酸含量提高了22.92%,有效提高了豆粕的营养和感官品质,为豆粕的进一步研究和应用提供了参考。     

混菌发酵对西拉葡萄酒香气品质的影响

为探究非酿酒酵母与酿酒酵母混合发酵对西拉葡萄酒香气品质的影响,以酿酒酵母单菌发酵为对照,分别将商业戴尔有孢圆酵母、本土美极梅奇酵母和本土葡萄汁有孢汉逊酵母与酿酒酵母顺序接种发酵,以及本土美极梅奇酵母和本土葡萄汁有孢汉逊酵母共同与酿酒酵母顺序接种发酵。采用顶空固相微萃取结合气相色谱质谱联用技术测定酒样的挥发性香气成分,并对葡萄酒进行基本理化指标检测和感官评价。结果表明：与单菌发酵相比,混合发酵处理酒样的乙醇含量降低了2.5%～4.0%,同时甘油含量增加了12.3%～15.3%,色度提升了3.6%～20.3%。此外,混合发酵处理酒样的挥发性香气物质总量增加了2.7%～19.5%,其中本土美极梅奇酵母与酿酒酵母混合发酵的酒样（FM）香气物质含量最丰富,乙酸异戊酯、乙酸苯乙酯、正己醇和异丁醇等化合物的含量显著增加。感官评价结果表明,FM处理的葡萄酒花香和果香味更为浓郁,香气更复杂并且具有良好的口感,整体评分最高。     

不同酵母对赤霞珠桃红葡萄酒香气的影响

利用CY3079、Zymaflore X16、TXL和STR四种不同类型的商业酵母发酵赤霞珠新鲜桃红葡萄酒,采用顶空固相微萃取（HS-SPME）结合气相色谱质谱（GC-MS）联用技术,分别对酒精发酵结束和瓶储陈酿一年的葡萄酒样品进行香气物质的定性与定量分析。结果表明,4种酵母发酵的赤霞珠桃红葡萄酒中香气物质的种类相似,但其含量差异显著。酒精发酵结束阶段,CY3079和Zymaflore X16酵母发酵的桃红葡萄酒中脂肪酸乙酯的含量高于其他酵母发酵的酒样,使它们具有更加浓郁的果香、甜香和花香;而Zymaflore X16和STR酵母产生乙酸异戊酯和乙酸苯乙酯的能力较强。经过一年的瓶储陈酿,所有处理的桃红葡萄酒中脂肪酸乙酯和高级醇乙酸酯的含量显著下降,导致其果香的强度降低,同时减少了不同酵母发酵酒样之间的差异。     

不同酵母发酵对葡萄酒香气成分的影响

分别采用天然酵母种群、本土优筛酿酒酵母菌株Y14和商业葡萄酒活性干酵母F15进行红葡萄酒发酵实验,采用固相微萃取结合气质色谱的方法对葡萄酒中的香气成分进行检测。结果表明,不同酵母发酵葡萄酒样中香气成分的种类和含量均具有明显差异,不同酒样中共有的主要香气成分有异戊醇、苯乙醇和异丁醇。     

高强脉冲电场处理对脱脂乳游离氨基酸和乳糖的影响研究

研究了高强脉冲电场处理对脱脂牛乳中游离氨基酸和乳糖含量的影响,结果表明:经电场处理后牛乳中游离氨基酸含量有所增加,且处理时间越长增加越多,而经电场处理后牛乳中的乳糖含量几乎不受影响。     

α—氨基酸在葡萄酒发酵中的变化

研究分析了葡萄酒原料之中的α－氨基酸的含量,以及添加酵母营养粉之后对α－氨基酸含量的影响;继而分析了新酒之中α－氨基酸的含量。α－氨基酸在发酵过程中的消耗,表明了酵母菌对α－氨基酸的利用情况。所以,为保证酒精发酵的顺利进行,在酒精发酵之前,往葡萄汁中添加酵母营养物质是必不可少的。     

4种酵母和2种发酵罐在蛇龙珠干红葡萄酒酿造中的应用

本试验在大生产条件下对4种酵母的使用效果进行了研究。结果表明：在烟台地区,D254酵母发酵的酒样单宁、总酚含量较高,酒的香气、口感、典型性较佳,比较适合于蛇龙珠干红的发酵。旋转发酵罐发酵的葡萄酒中单宁、总酚含量远高于立式罐发酵的葡萄酒,适合于陈酿型葡萄酒的酿造。     

不同果胶酶和酵母菌对葡萄酒中白藜芦醇及其二聚体的影响

采用高效液相色谱直接进样分析,测定了3种果胶酶处理、4种酵母发酵的葡萄酒中res、ε-viniferin、δ-viniferin等葡萄主要芪化物的含量.结果表明:7种葡萄酒中都含有较多的res、ε-viniferin和8-viniferin,不同果胶酶、酵母的选用均能影响到葡萄酒中的res、ε-viniferin和ε-viniferin的浸出效果.Uhrazyme Premium果胶酶酒样中ε-viniferin含量为2.187 mg/L,而Ex-v酒样中为1.926mg/L,796酵母酒样中res含量为1.193 mg/L,而CMS酒样仅为0.682 mg/L,δ-viniferin在D254酵母酒样中的含量为2.297 mg/L,而在Oneferm Color酒样中仅为1.850 me/L.Uhrazyme Premium果胶酶和D254、796酵母对果皮中上述芪化物的浸提效果较好.     

4种酵母和2种发酵罐在蛇龙珠干红葡萄酒酿造中的应用

本试验在大生产条件下对4种酵母的使用效果进行了研究.结果表明:在烟台地区,D254酵母发酵的酒样单宁、总酚含量较高,酒的香气、口感、典型性较佳,比较适合于蛇龙珠干红的发酵.旋转发酵罐发酵的葡萄酒中单宁、总酚含量远高于立式罐发酵的葡萄酒,适合于陈酿型葡萄酒的酿造.     

酵母菌氨基酸代谢与发酵饮料风味

本研究依据酵母菌相应发酵液的呈味氨基酸（游离精氨酸、谷氨酸）含量以及影响发酵物风味的游离含硫氨基酸（半胱氨酸、蛋氨酸）的含量，结合品评人员的主观品评，选用菌种用于饮料发酵试验，有效地改善了酵母发酵饮料的风味。     

中国主产干红葡萄酒中氨基酸含量对照与探讨

测定了市售国内葡萄主产地的 8个主要品牌干红葡萄酒中的游离氨基酸含量 ,发现不同葡萄品种之间游离氨基酸含量差别很大 ,新疆天山北坡地区所产干红葡萄酒中含量最高 ,达到 15 0 8mg/L ,与美国加州优质干红葡萄酒相当 ,其余品牌大多数在 70 0～ 1 1 0 0mg/L范围内变化 ,有 2个样品含量低于 30 0mg/L。L 脯氨酸是所有葡萄酒中氨基酸的主体 ,也是各样品含量差异最大的氨基酸 ,这与葡萄品种、气候、发酵工艺及酒的陈酿时间有关。     

不同有机氮源对葡萄酒发酵的影响

分别使用酵母浸粉和混合氨基酸作为模拟葡萄汁（36 °Bx）的有机氮源发酵葡萄酒,以保证葡萄酒的正常发酵和最终产品品 质。 通过测定发酵过程中的二氧化碳生成量、还原糖、可同化氮、甘油和挥发性化合物含量变化,比较酵母浸粉和混合氨基酸对葡萄酒 品质的影响。 结果表明,使用酵母浸粉耗还原糖量为295.7 g/L,生成乙醇97.20 g/L、甘油26.50 g/L、乙酸1.08 g/L和乙酸乙酯46.05 mg/L, 与使用混合氨基酸相比,多消耗还原糖130.47 g/L,多生成乙醇46.14 g/L、甘油7.95 g/L和乙酸0.54 g/L,增幅分别为78.95%、90.38%、 42.84%和99.35%。 使用酵母浸粉比混合氨基酸的发酵程度大,速度快。 因此,可用适量酵母浸粉替代混合氨基酸作为葡萄酒发酵的 氮源补充。     

葡萄酒酿造过程中氨基酸含量变化的研究

应用HPLC对我国4个产区多个品种葡萄酒酿造过程样品中氨基酸含量变化趋势进行了研究,结果表明,L-脯氨酸是所有葡萄汁中氨基酸的主体,也是各样品含量差异最大的氨基酸;红葡萄酒中含脯氨酸、苏氨酸、赖氨酸等20种氨基酸,其中以脯氨酸含量最高,发现不同葡萄品种之间游离氨基酸种类和含量有差别,这与葡萄品种、气候、发酵工艺有关。     

东山老米酒酿造过程中酵母菌的分离鉴定及其品质分析

目的 本文对传统东山老米酒的发酵特性进行了比较全面研究。方法 首先利用26S rDNA序列分析法对酒曲中的酵母菌进行了分离鉴定,借助高效液相色谱法测定酒中的氨基甲酸乙酯,利用气相色谱-质谱联用法分析了老米酒中的风味物质,同时还用氨基酸自动分析仪测定了游离氨基酸种类。结果 分离得到的菌株有3株为酿酒酵母,1株为白色隐球菌;老米酒中氨基甲酸乙酯含量处于较低水平,尤其是陈酿中仅含0.6 mg/L;风味物质以醇、酯类为主,如苯乙醇、琥珀酸二乙酯,酯类随酒的陈化而逐渐增多;老米酒中组氨酸和精氨酸含量较高,导致酒中苦味氨基酸含量高于60%,同时氨基酸含量在陈化过程中逐渐下降。结论 东山老米酒的发酵以酵母发酵为主,发酵产生的氨基甲酸乙酯的含量处于较低水平,且随着老米酒的陈化而降低。     

Influence of yeast strain,immobilisation and ageing time on the changes of free amino acids and amino acids in peptides in bottle‐fermented sparkling wines obtained from Vitis vinifera cv. Emir

This paper reports the influence of yeast strain, immobilisation and ageing time on the free amino acids and amino acids in peptides of sparkling wine made by the traditional method from the Emir grape variety over a period of 365 days in vintages 2004 and 2005. Four sparkling wines were obtained from the same base wine using yeast strains (both immobilised and free Saccharomyces bayanus and Saccharomyces oviformis). The analysis of variance and cluster revealed that there were significant differences between free amino acids and amino acids in peptides due to ageing time. However, the yeast strain affected most of the free amino acids and amino acids in peptides in only the 2004 vintage. The total amount of free amino acids was higher in the wine made with the S. oviformis compared to S. bayanus. Furthermore, there were no significant differences between the use of immobilised and free yeast in cases of free amino acids and amino acids in peptides.     

Changes on free amino acids during the alcoholic fermentation of strawberry and persimmon

Changes in amino acids and ammonium were monitored during the alcoholic fermentation of strawberry and persimmon purees. Fermentations were carried out either by autochthonous or by commercial yeasts. The amino acid content in strawberry and persimmon was lower than that of grapes but enough to successfully perform the alcoholic fermentation, showing a different consumption pattern. Arginine, although is not present in the most strawberry substrates, appears in strawberry wines (2.75–3.36 mg L^?1). Additionally, as opposed to grape wine, an exceptional high consumption of proline was observed during the alcoholic fermentation of strawberry purees. The consumption of amino acids was highly influenced by the substrate and the S. cerevisiae strain used for the fermentation process. These results were confirmed by principal component analysis, which was able to group the samples based on substrate, harvest or yeast strain, considering the amino acids as variables.     

Sedimentation clarification of viura musts. Utilization of amino acids during fermentation

The influence of sedimentation on viura must's concentration of free amino acids and changes during fermentation were studied; the results were compared with an unclarified sample. The protein fraction was reduced by this treatment; the amino nitrogen increased slightly in the decanted must, and the concentration of ammonium nitrogen was similar in both samples. The decanted must had a greater concentration for most of the amino acid constituents of proteins, neutral as well as basic. This treatment did not alter the medium sufficiently to modify yeast utilization of these nutrients during fermentation; in fact, in both samples, basic, neutral, and acidic amino acids were consumed in a similar manner in the first half of fermentation (until 50% sugar consumption) and were excreted similarly in the freshly produced wine.     

Influence of SO2 on the consumption of nitrogen compounds through alcoholic fermentation of must sterilized by pulsed electric fields

The aim of this work was to study the influence of SO₂ on the use of nitrogenous compounds by yeast during wine alcoholic fermentation. Thus Parellada must was sterilized by a pulsed electric field treatment and inoculated with Saccharomyces cerevisiae Na33 strain. The fermentations were carried out with SO₂ (20 mg/l) and without SO₂. Results showed that yeast better consumed the amino acids in the first half of fermentation in the presence of SO₂. The final concentration of amino acids in the obtained wine was greater when the must was fermented without SO₂ than when the latter compound was present. Therefore, the presence of SO₂ facilitated the consumption of amino acids and, hence, such wine should have more complex flavour and better microbiological stability than that obtained from fermentation without SO₂.     

紫甘薯红酒酿造工艺优化及成分分析

目的：以冀紫薯1号为原料,采用酶解淀粉与酵母菌酒精发酵相结合,制得感官色泽酷似红葡萄酒的紫甘薯红酒。方法：通过正交试验优化淀粉液化、糖化和发酵的工艺条件,气相色谱-质谱联用技术分析检测紫甘薯红酒的香气成分,高效液相色谱技术分析检测氨基酸和有机酸含量。结果：当料液比为1∶3（m/V）,淀粉酶添加量3 U/g,92 ℃液化60 min,再加入糖化酶300 U/g,控制50 ℃、pH 4.5、糖化60 min,淀粉水解率达92%。在紫甘薯汁中接入2×106 个/mL安琪活性干酵母菌,于23 ℃、pH 4.0,发酵7 d,酒精体积分数12.4%。紫甘薯红酒中含有46 种香气物质、17 种氨基酸和9 种有机酸,花色苷含量为145 mg/L。结论：冀紫薯1号所酿造的紫甘薯红酒风味独特、营养物质齐全,具有开发价值。     

有机酸含量对葡萄酒发酵的影响

为了考察有机酸含量对葡萄酒发酵的影响,在初始有机酸含量分别为4 g/L、7 g/L和10 g/L的模拟葡萄汁中接种酵母,于25 ℃发酵,比较不同初始有机酸含量对葡萄酒发酵过程中酵母生长、降糖、有机酸及挥发性化合物含量的影响。结果表明,初始有机酸含量7 g/L时酵母生长和耗糖最慢,乙醇和乙醛产生量最低;随初始有机酸含量升高,pH值、酒石酸、苹果酸、乳酸、乙酸、总酸、乙酸乙酯和总酯含量呈下降趋势;琥珀酸、正丙醇、异丁醇、异戊醇及总高级醇含量呈上升趋势;但对β-苯乙醇、正丁醇及丁酸乙酯含量影响较小。初始有机酸含量10 g/L的葡萄酒发酵过程酵母生长快、降糖最快,产酸含量适中,同时香气较好。因此,葡萄酒发酵的适宜初始有机酸含量为10 g/L。