The evaluation of remedial treatments for wine affected by Harmonia axyridis

This study evaluated the efficacy of a range of commercially available fining agents and other interventions on reducing 2‐isopropyl‐3‐methoxypyrazine (IPMP) concentration and taint characteristics of white and red wine affected by Harmonia axyridis (HA). Wines fermented in the presence of HA beetles were treated with bentonite, activated charcoal, oak chips, deodorized oak chips and either ultraviolet (red wine) or visible (white wine) light. IPMP concentrations were lowered by activated charcoal in white wine and deodorized oak in red wine. Treatment with oak chips reduced the intensity of HA‐associated sensory attributes (‘ladybug taint’) in both white and red wines, while other applications generally had no effect on white wine and limited effect on red wines.     

Determination of ortho- and retronasal detection thresholds for 2-isopropyl-3-methoxypyrazine in wine

ABSTRACT:  2-isopropyl-3-methoxypyrazine (IPMP) is a grape-derived component of wine flavor in some wine varieties as well as the causal compound of the off-flavor known as ladybug taint (LBT), which occurs when Harmonia axyridis beetles are incorporated with the grapes during juice and wine processing. The main objective of this study was to obtain robust estimates of the orthonasal (ON) and retronasal (RN) detection thresholds (DTs) for IPMP in wines of differing styles. The ASTM E679 ascending forced choice method of limits was used to determine DTs for 47 individuals in 3 different wines—Chardonnay, Gewürztraminer, and a red wine blend of Baco Noir and Marechel Foch. The group best estimate thresholds (BETs) obtained for IPMP (ng/L) were Chardonnay, ON: 0.32; Gewürztraminer, ON: 1.56, RN: 1.15, and red wine blend, ON: 1.03, RN: 2.29. A large variation in individual DTs was observed. Familiarity with LBT was inversely correlated with DTs for Gewürztraminer, and no difference in thresholds was observed between winemakers and nonwinemakers. We conclude that the human DT for IPMP is extremely low and influenced significantly by wine style and evaluation mode. We recommend against the reporting of single-threshold values for wine flavor compounds, and encourage the determination of consumer rejection thresholds for IPMP in wine.     

Impact of Multicolored Asian Lady Beetles on the Sensory Properties of Concord and Niagara Grape Juice

ABSTRACT: The presence of Multicolored Asian Lady Beetles (MALB) in grape juice is increasingly problematic. The overall objective of this study was to determine the specific sensory impacts of MALB on Concord and Niagara grape juice. The aroma threshold for MALB-taint in both juices was determined and expressed as the best estimate threshold (BET). The aroma BET for MALB-taint in Concord grape juice was 1.8 and 0.65 MALB/L Niagara grape juice. The specific sensory attributes of the grape juices influenced by the presence of MALB were then described. In Concord grape juice, trained panelists (n = 9) found significant increases in vegetal aroma and earthy flavor as MALB concentration increased from 0.45 to 7.2 MALB/L. In Niagara grape juice, with increasing MALB concentration, trained panelists (n = 8) indicated significant decreases in honey and sweetness with corresponding increases in sourness, astringency, and vegetal and earthy aromas and flavors (P < 0.05). For both aroma and flavor, consumer rejection studies were performed using paired preference comparisons of control juice to MALB-tainted grape juice. For Concord grape juice, consumers (n = 60) rejected the aroma of MALB-tainted juice at 1.8 MALB/L and the taste/flavor of the MALB-tainted juice at 3.6 MALB/L. For Niagara juice, consumers rejected the aroma of the juice at 3.6 MALB/L. This study demonstrated the presence of MALB negatively impacts the sensory properties of Concord and Niagara grape juice. Grape juice processors may use this research for quality control measures and for establishing tolerance limits. Practical Application: The Multicolored Asian Ladybeetle (MALB), initially used for biocontrol, has been shown in previous literature to impact the sensory properties of wines. The presence of MALB in grape juice is now becoming problematic; however, there is little research describing the specific sensory impacts of MALB on grape juice. This study examined the sensory impact of MALB on both Concord and Niagara grape juice. While the threshold and trained panel evaluations from this study provide valuable sensory profile information, grape juice processors may be particularly interested in the consumer rejection of MALB-tainted grape juice as they can use this research for quality control measures and for establishing tolerance limits.     

橡木桶陈酿对红葡萄酒的作用与影响的研究

阐述了木桶陈酿对红葡萄酒的微氧熟化、增强理化稳定性、改善风味特征的重要作用,同时比较了不同植物来源橡木桶呈香组份的特性,说明了木桶容积、新旧程度对陈酿效果的影响,并且提出了如何根据葡萄酒的性质选择橡木桶的建议。     

Interactions Between Wine Lees and Polyphenols: Influence on Oxygen Consumption Capacity During Simulation of Wine Aging

ABSTRACT: During wine aging on lees, some membrane lipids of yeast lees, in contact with dissolved oxygen at low concentration, may undergo mild oxidation explaining the capacity of yeast lees to consume oxygen. We studied the cross-reactivity of complex polyphenols and tannins from wine and yeast lees towards oxygen during simulation of wine aging. We observed a total decrease of oxygen consumption capacity of mixed yeast lees and wine polyphenol by comparison with the reactivity of each component studied alone. A strong loss of reactivity of yeast lees towards oxygen was observed when separated from soluble polyphenols, although only a fraction of the total polyphenols remained adsorbed on lees.     

甜酒药中的菌群分析及保鲜甜酒制作

将传统生产的甜酒药进行微生物的种类分析,得出甜酒药中存在3大主要菌群:根霉3.6×107 CFU/g,细菌9.5x103 CFU/g和酵母茵1.7x 105 CFU/g.对分离出来的根霉进行淀粉水解酶的活性测定,得出甜酒药中根霉的淀粉水解酶活力为2380.6U.保鲜甜酒的制作最佳工艺为发酵时间为36h左右,发酵温度28...     

青稞酒的老熟机理探索

“酒是陈的香”,青稞酒的香气口感同样随着贮存期的延长而自然达到陈化、老熟的目的,从而赋予青稞酒清雅纯正、绵甜爽净、醇厚丰满、回味怡畅、诸味协调的风味特色。同时,科学合理的储酒设备和方法也能起到一定的催陈老熟作用。探索在充分利用现有设备、设施的基础上,通过变换条件和方法就能达到陈化、老熟效果的机理。     

Influence of Fermentation Process on the Anthocyanin Composition of Wine and Vinegar Elaborated from Strawberry

Anthocyanins are the major polyphenolic compounds in strawberry fruit responsible for its color. Due to their sensitivity, they are affected by food processing techniques such as fermentation that alters both their chemical composition and organoleptic properties. This work aims to evaluate the impact of different fermentation processes on individual anthocyanins compounds in strawberry wine and vinegar by UHPLC‐MS/MS Q Exactive analysis. Nineteen, 18, and 14 anthocyanin compounds were identified in the strawberry initial substrate, strawberry wine, and strawberry vinegar, respectively. Four and 8 anthocyanin compounds were tentatively identified with high accuracy for the 1st time to be present in the beverages obtained by alcoholic fermentation and acetic fermentation of strawberry, respectively. Both, the total and the individual anthocyanin concentrations were decreased by both fermentation processes, affecting the alcoholic fermentation to a lesser extent (19%) than the acetic fermentation (91%). Indeed, several changes in color parameters have been assessed. The color of the wine and the vinegar made from strawberry changed during the fermentation process, varying from red to orange color, this fact is directly correlated with the decrease of anthocyanins compounds.     

黄酒中陈香物质来源的探讨

利用静态顶空气相色谱分析了陈年黄酒和新酒的香气物质,并对比不同贮存容器中黄酒风味物质的变化,最后对酒样进行感官品评。通过分析比较发现,玻璃瓶中的黄酒贮存5年后,保留了新酒的特殊风味,不具有陈年黄酒的陈香,并且其醇类、酯类物质的含量与陶坛中5年陈的黄酒一致。两种贮存方式中,最大的区别是由于各自所用容器的密封性不同而导致两者氧化速度的巨大差异,玻璃瓶内黄酒中醛类物质的含量远低于普通陈年黄酒。     

酒类产品超声陈化技术的研究进展

酒类自然陈化存在时间过长、耗资大等缺点,而超声陈化可以利用空穴效应,提高酒中分子的活化能,加快反应速度,从而减短陈化时间。本文首先介绍酒类超声陈化的作用机理,综述了葡萄酒、白酒、黄酒以及果酒的超声陈化研究进展,最后,对超声陈化的状况进行总结,提出新的研究思路。     

米酒对D-半乳糖致衰老小鼠抗氧化作用的研究

通过建立D-半乳糖诱导的衰老小鼠模型,研究米酒对衰老小鼠的抗氧化作用.实验测定了各组小鼠血清中过氧化氢酶(CAT)、丙二醛(MDA)、总超氧化歧化酶(SOD)指标的变化.结果表明,米酒能显著提高衰老小鼠血清中CAT(P＜0.05)和总SOD(P＜0.05)的活力,降低MDA(P＜0.01)的含量.米酒通过抗氧化作用,有效抑制了衰老小鼠衰老症状的发展.     

陈酿时间对发酵型香菇酒香气成分及酒体风味的影响

采用顶空固相微萃取与气相色谱-质谱联用技术对发酵型香菇酒陈酿早期香气成分变化进行动态检测,通过峰面积归一法计算各香气成分相对含量,并结合相对香气活度值（relative odor activity value,ROAV）进行分析。结果表明：发酵型香菇酒在陈酿早期形成大量香气成分,检出54 种,其中1-辛烯-3-醇、异戊醇、癸酸乙酯等8 种挥发性香气化合物是发酵型香菇酒具有独特风味的主要原因。陈酿早期香菇酒香气成分变化较大,醇类与酸类香气物质的相对含量总体下降,酯类香气物质相对含量明显上升,其他类香气物质变化不大。陈酿60 d及陈酿180 d的成品香菇酒的香气成分相对含量及ROAV,差异不显著（P＞0.05）。证明在陈酿早期即形成了发酵型香菇酒的主体香,提示生产中可适当缩短发酵型香菇酒的陈酿时间,缩短生产周期,提高生产效率。     

橡木桶陈酿对红葡萄酒中黄烷-3-醇和原花色素的影响

本文以华夏酿酒有限公司2004年度赤霞珠为试材,研究了美洲、欧洲和欧美三种类型橡木桶陈酿对黄烷-3-醇和原花色素含量及组成的影响。结果表明,橡木桶陈酿过程中,(-)-表儿茶素((-)-epicatechin,EC)、(-)-表儿茶素没食子酸酯((-)-epicatechingallate,ECG)、(-)-表棓儿茶素没食子酸酯((-)-epgallocatechingallate,EGCG)含量上升,(+)-儿茶素((+)-catechin,CAT)保持相对稳定,而(-)-表棓儿茶素((-)-epigallocatechin,EGC)略有下降。原花色素含量下降,平均聚合度降低。不同类型的橡木桶对两者含量的影响不同。     

黄酒自然光波催陈的研究

介绍了一种自然光波催陈黄酒的方法。结果表明,黄酒经特殊透光材质的玻璃罐贮存一年后,其还原糖、酒精度、非糖固形物含量均高于陶坛酒样;总酸含量低于陶坛酒样;氨基酸态氮含量基本相同。玻璃罐酒样颜色较深,香味更醇厚浓郁,口感更醇厚鲜爽,酒体丰满协调。     

杨梅果酒降酸技术研究

对杨梅果酒降酸技术进行了研究。试验表明，杨梅果酒的降酸剂以K2C4H4O6配合K2CO3的使用效果最好，总酸为0．93％的杨梅果酒添加1．6g／L的K2C4H4O6 0．8g／L的K2CO3，总酸可降至0．79％，不仅改善了口感还保持了果酒的稳定性。     

孝感米酒中乳酸菌的分离及其对黄酒品质的影响

目的:探明孝感米酒中乳酸菌的种类及其对黄酒品质的影响。方法:采用传统可培养方法使用MRS培养基、厌氧工作站,对孝感米酒中乳酸菌进行分离,并接入黄酒对黄酒发酵过程进行干预,进而通过分析黄酒有机酸与滋味等理化特征来评价乳酸菌的发酵特性。结果:从孝感米酒中分离到9株乳酸菌,基于16S rDNA基因对乳酸菌分离株进行了系统发育分析,结果显示它们属于魏斯氏菌属(Weissella)、片球菌属(Pediococcus),种水平上分为戊糖片球菌(Pediococcus pentosaceus)、融合魏斯氏菌(Weissella confusa)、食窦魏斯氏菌(Weissell acibaria)。将这9株菌应用于黄酒发酵制作,在菌株融合魏斯氏菌MJ3-1与MJ4-1、戊糖片球菌MJ6-1、食窦魏斯氏菌MJ8-1干预下,黄酒中乳酸含量显著增加(p<0.05),苹果酸含量显著减少(p<0.05);同时黄酒的滋味中咸味和丰度有显著增加(p<0.05)。总体上来说,乳酸菌对黄酒滋味的影响由酸味、鲜味与丰度引起。结论:融合魏斯氏菌MJ4-1能增加黄酒乳酸,并降低苹果酸含量作用最强,适用于黄酒复合型发酵剂的研发。     

黄酒对小鼠抗疲劳能力和衰老小鼠免疫器官的影响

目的：研究黄酒对正常小鼠抗疲劳能力和D-半乳糖所致亚急性衰老小鼠免疫器官的影响。方法：抗疲劳能力实验中,小鼠分别灌胃给予双蒸水（0.25 mL/d）、高（0.4 mL/d）、中（0.25 mL/d）、低（0.15 mL/d）剂量的黄酒（乙醇体积分数为8%）15 d,小鼠游泳后检测肝糖原（hepatic glycogen,HG）、尿素氮（blood ureanitrogen,BUN）和血乳酸（blood lactic acid,BLA）含量的变化。在黄酒对亚急性衰老小鼠免疫器官影响的实验中,采用腹腔注射D-半乳糖建立亚急性衰老小鼠模型,分别灌胃双蒸水、酒精和不同剂量的黄酒,每天1 次,连续灌胃56 d,测定小鼠胸腺指数、脾脏指数和亚急性衰老模型建立前后的体质量增值。结果：黄酒能显著提高小鼠体内HG的含量（P＜0.01）;增加运动后小鼠BLA增长率（P＜0.05）和BUN的廓清率（P＜0.05）;黄酒能抑制衰老小鼠胸腺（P＜0.01）和脾脏（P＜0.05）质量的减少,有助于衰老小鼠的体质量增长（P＜0.05）。结论：黄酒能提高小鼠的抗疲劳能力,增强衰老小鼠的免疫能力。     

荔枝玫瑰酒延缓小鼠皮肤衰老的研究

为探究荔枝玫瑰酒对衰老小鼠皮肤的干预作用,选用60只ICR小鼠进行实验分析.将小鼠分为正常组(饲喂含质量分数12％乙醇的饮用水),D-半乳糖处理组(饲喂含质量分数12％乙醇的饮用水),VC对照组(饲喂450 mg/kg(以体质量计)的VC),低、中、高剂量荔枝玫瑰酒组(分别饲喂10、20、40 mL/kg(以体质量计)...     

Maintenance and Protection of Yeast Morphology by Contact with Wine Polyphenols During Simulation of Wine Aging on Lees

Scanning electron microscopy was used to monitor yeast cell morphology during simulated wine aging. Although yeast cells in lees in the absence of wine polyphenols rapidly reach a flat shape after the end of alcoholic fermentation, they keep a spherical (and almost intact) shape in the presence of wine polyphenols. We confirmed these visual observations by calculating the dynamic viscosity of the corresponding lees. Because yeast autolysis is not affected by the contact with wine polyphenols, such maintenance of yeast morphology maybe the consequence of protection of some constitutive parts of yeast cell walls by wine polyphenols toward the action of hydrolytic enzymes.