不同奶啤风味成分分析

采用气相色谱-质谱联用（GC-MS）技术和高效液相色谱（HPLC）法测定4种奶啤主要风味成分及有机酸,并结合各物质的香气活性值（OAV）进行主成分分析（PCA）和香气轮分析。结果表明,奶啤中共鉴定出58种风味成分,其中醇类11种、酯类23种、酸类6种、醛和酮7种、其他类物质共11种。其中天润奶啤中醇类物质相对含量较高,达到34.92%,酯类和酸类含量最低,分别为11.32%和28.41%,金河、西域春、海伦司奶啤中三种酯类和酸类含量最高,酯类含量分别为25.39%、23.61%、30.62%,酸类含量分别为43.62%、43.91%、40.59%。主要挥发性物质为乙醇、苯乙醇、乙酸苯乙酯、正癸酸。奶啤中含草酸、柠檬酸、苹果酸、富马酸和乳酸5种有机酸,柠檬酸含量最高,且柠檬酸和乳酸为主要呈香物质。     

赤霞珠葡萄酒苹果酸-乳酸发酵过程中香气成分动态变化

为了研究苹果酸-乳酸发酵过程对葡萄酒香气的影响,采用顶空固相微萃取（HS-SPME）结合气相色谱-质谱联用（GC-MS）对赤霞珠葡萄酒苹乳发酵过程中香气物质动态的变化进行了监测。结果表明：在葡萄酒苹乳发酵过程中共检出55种不同的香气成分,包括22种酯类、10种醇类、8种酸类、7种醛类、4种酮类、3种萜烯类和1种酚类,其中酯类、醇类和酸类化合物为苹乳发酵过程中主要香气成分。相比于发酵起始阶段（0 d）,发酵末期（18 d）葡萄酒中的酯类和酸类化合物的质量分数由20.7%和1.08%上升至25.61%和2.33%,主要包括乙酸乙酯、己酸乙酯、月桂酸等,这类香气物质能够赋予葡萄酒浓郁的果香,而由于酯化反应醇类化合物的质量分数由42.89%下降至29.01%,主要变化为异戊醇等高级醇质量分数的降低。由此看出,葡萄酒经过苹乳发酵不仅增强了酒体的水果类香气还提高了葡萄酒的安全性。     

GC-MS对不同奶味香精成分分析及香气变化规律

利用GC-MS分析方法,比较了自制的天然酶解奶味香基和不同奶味香精的组成成分及香气变化规律。复配香精A、复配香精B、复配香精C、复配香精D、天然发酵香精E、自制酶解香基F中分别鉴定出18、22、30、15、30、14种组分,组分种类包括酸类、内酯类、脂肪酸酯类、芳香及杂环类、酮类、醇类、烃类等7种类型。不同复配香精之间的区别主要是酸类、内酯类和脂肪酸酯类之间的比例和数量有所不同,进口天然香精E各组分分布较均衡且含有较多的芳香及杂环类,自制酶解香基F的酸类比例较大以及特征性香气成分含量少。增加香气成分的种类,均衡各香气成分间的分布,可从一定程度上提高香气品质。     

川藏高原不同年份霞多丽冰酒香气成分GC-MS分析

采用气相色谱质谱-联用分析法分别对2009年至2013年五个年份的川藏高原霞多丽冰酒进行了香气成分分析。结果表明,五个年份冰酒中所含的主要香气成分为酯类,醇类和酸类物质等。在2009年至2013年的冰酒中分别检测到26种、22种、53种、23种和38种香气成分。2009年冰酒中酯类10种（75.44%）,醇类6种（11.16%）,酸类3种（7.36%）和萜烯类3种（2.30%）;2010年酯类9种（74.47%）,醇类5种（14.67%）,酸类3种（6.75%）和萜烯类2种（1.94%）;2011年酯类16种（62.77%）,醇类10种（16.49%）,酸类4种（8.6%）和萜烯类3种（2.49%）;2012年酯类9种（78.8%）,醇类3种（8.92%）,酸类3种（9.16%）和萜烯类3种（1.62％）;2013年酯类14种（66.13%）,醇类4种（10.83%）,酸类4种（13.05%）和萜烯类4种（4.65%）。     

自然发酵与接种发酵燕麦醪糟的挥发性成分分析

采用顶空固相微萃取与气相色谱-质谱联用技术分析自然发酵与接种发酵2 种方式燕麦醪糟的挥发性成分,探讨2 种方式下燕麦醪糟挥发性成分的差异性,进而为接种发酵燕麦醪糟工业化生产提供理论依据。结果表明,2 种发酵方式生产燕麦醪糟的挥发性香气成分分别为62、65 种,主要包括酯类、酸类、醇类、醛酮类、杂环类、烃类,主成分分析发现酯类、醇类、杂环类为正影响挥发性物质;接种发酵燕麦醪糟的主要挥发性香气成分为醇类（58.31%）、酯类（20.70%）、酸类（16.75%）,自然发酵燕麦醪糟主要挥发性香气成分为酸类（61.94%）、酯类（18.89%）、醇类（13.58%）;接种发酵燕麦醪糟的酯类、醇类、杂环类成分含量显著高于自然发酵组,酸类成分显著低于自然发酵组。挥发性香气组分分析有助于明确燕麦醪糟接种发酵的可行性,以期为接种发酵燕麦醪糟的品质评价和定向生产提供理论基础。     

兼香型年份酒中香味物质的分析

通过单因素试验优化顶空固相微萃取（HS-SPME）条件,并结合气相色谱-质谱（GC-MS）技术研究兼香型年份酒中香味物质成分含量及差异。结果表明,最佳HS-SPME萃取条件为酒样酒精度14%vol,萃取温度40 ℃,萃取时间30 min,解吸时间5 min。GC-MS法共鉴定出67种挥发性风味物质,包括50种酯类,3种醇类,5种酸类,1种芳香族化合物,1种含硫化合物,2种呋喃类,3种酮类和2种醛类。酯类、醇类、酸类和呋喃类总含量随贮藏年份增长呈现上升趋势,醛类和酮类总含量变化规律不明显。经香气活度值（OAV）分析,确定出22种（OAV＞1）成分对白酒香味有贡献,其中有9种（OAV＞10）为重要香气成分,酯类为白酒香气的主要贡献物质。     

赤霞珠果醋香气成分的GC-MS分析

采用溶剂萃取法提取、富集赤霞珠果醋中的香气成分,经气相色谱-质谱（GC-MS）联用分析,综合谱库检索技术对化合物进行鉴定。结果表明,葡萄皮渣酿造果醋样品（SP1）和葡萄果汁酿造果醋（SP2）分别鉴定出48种、20种香气组分。其中酯类、酸类和醇类化合物为葡萄果醋样品中最主要的香气成分,在SP1、SP2样品中酯类、酸类和醇类化合物的相对含量分别为58.29%和52.39%,24.63%和35.10%,7.35%和11.37%。     

大米奶啤饮料的研制

以大米、麦芽、牛乳为主要原料，利用乳酸菌、酵母菌进行两阶段发酵，研制大米奶啤饮料，以感官评分为指标，通过单因素、正交实验对大米糖化、大米奶啤饮料的加工工艺和产品配方进行了优化。结果表明：利用乳酸菌发酵牛乳完成第一阶段发酵，将粉碎后的大米，按照米水比1∶9的比例，100℃煮沸30 min后，92℃时加入α-淀粉酶糖化1.5 h，过滤得到大米汁，加入麦芽汁、第一阶段的发酵乳（大米汁∶发酵乳质量比为2∶5）和白砂糖（质量分数为4%），再利用酵母菌完成第二阶段发酵，酿制成的大米奶啤饮料不仅米香浓郁、奶香醇厚、麦香柔和，风味饱满，而且酸甜可口，具有适度杀口感，口感细腻爽滑。     

桂葡3号干白葡萄酒香气特征分析

采用顶空-固相微萃取（HS-SPME）结合气相色谱-质谱联用（GC-MS）分析广西一年两收栽培模式下桂葡3号夏果酿造的干白葡萄酒挥发性成分,应用香气活性值（OAV）法对活性和特征香气成分进行鉴定,分析葡萄酒香气特征。结果表明,桂葡3号干白葡萄酒共鉴定出43种挥发性成分,包括醇类9种、酯类25种、醛酮类3种、酸类2种,其他类4种。挥发性成分总含量达32.11 mg/L,醇类和酯类成分占了种类和含量的90%以上,是构成桂葡3号干白葡萄酒香气特征最主要的挥发性成分类别。桂葡3号干白葡萄酒特征性香气成分有己酸乙酯、乙酸乙酯、癸酸乙酯、乙酸己酯、辛酸乙酯、壬酸乙酯、异戊醇等,构成了以青苹果、菠萝、柑橘为主的果香,以及玫瑰为主的花香等香气特征。     

HS-SPME-GC-MS结合感官评价分析丹凤佳酿白酒的挥发性风味成分

为了解丹凤佳酿白酒的香气特征,利用顶空固相微萃取（HS-SPME）结合气相色谱-质谱联用（GC-MS）仪对该酒的挥发性成分进行分析,并结合感官检验分析该酒的主要香气轮廓。结果表明,从丹凤佳酿白酒中共鉴定出45种挥发性成分,包括酯类32种、醇类6种、醛酮类5种、酸类1种和其他类挥发性成分1种,其相对含量分别为94.51%、2.40%、1.77%、1.25%和0.07%,其中酯类、醇类和醛酮类为主要挥发性风味成分,醇香和果香是丹凤佳酿白酒的主要香气特征。该结果对研究特色浓香型白酒香气特点以及改良白酒的酿造工艺提供了数据参考。     

响应面法优化风味驴乳酸奶发酵工艺的研究

在驴乳中添加牛乳粉制作酸奶,通过单因素试验和响应面优化法研究了风味驴乳酸奶最佳发酵工艺。结果表明,以牛乳粉添加量、发酵温度和发酵时间为自变量,以感官评价为因变量,响应面法优化出风味驴乳酸奶的最佳发酵工艺为：牛乳粉添加量10%、发酵温度42 ℃、发酵时间5.5 h。在此优化条件下,风味驴乳酸奶口感细腻爽滑,酸甜适口,有浓郁的驴乳香味与滋味,感官评分达到92分,与预测值（90.85分）相差较小。产品的理化及微生物指标均符合相关国标要求。     

Physicochemical characterization of sahti,an ‘ancient’ beer style indigenous to Finland

Sahti, a strong, unhopped farmhouse beer flavoured with juniper, is still actively brewed in rural areas in Finland. Presented here is the first comprehensive analysis of the physical and chemical properties of this unique beer style. Twelve sahti samples from the southwest of Finland were analysed and, while properties varied, the beers generally had high levels of alcohol (mean = 7.9% ABV) and high residual extract (mean = 9.5°P). Foam stability was negligible, as is typical for the style, and glycerol concentrations at 3.1 – 4.7 g L^?1 were higher than in reference beers (commercial lager, wheat beer and porter). These features may be attributed to the very high gravity conditions employed in brewing sahti beers. Bitterness levels were relatively low (3–13 IBU) owing to the absence or moderate use of hops. All samples contained detectable levels of the clove‐like compound 4‐vinylguaiacol owing to the use of baker's rather than brewer's yeast for brewing. Concentrations of higher alcohols and esters were high, with many individual aroma compounds being above the normal flavour thresholds. Results have highlighted the uniqueness of this style of beer in comparison to commercially available beers and have contributed to our understanding of the reasons for the particular sensorial properties of this traditional beer style. Copyright © 2015 The Institute of Brewing & Distilling     

牛乳经酵母菌和乳酸菌发酵生产低醇乳酒的研究

用鲜牛乳为主要原料,添加蔗糖和营养素等辅料,经酵母和乳酸菌混合接种发酵,生产出低醇乳酒。通过对2种菌发酵方式的选择、协同性发酵实验、乳酸菌接种量和营养素的添加、发酵条件优化及发酵过程分析和发酵终点确定的研究,结果表明,当蔗糖添加量为10%时,乳酸菌的接种量为1%;牛乳酒生产的最佳配方及工艺条件是牛乳用量30%,营养素添加量70mg/L,酵母接种量8%,温度28℃。经生产性实验,在总发酵时间28h,乳酒产品酒精含量达到2·02%,呈乳白色,状态均匀,泡沫细腻,乳香、酒香和谐一体。     

蓝莓果醋饮料的研制及香气物质检测

为研制出一款口味独特,品质优良的蓝莓果醋饮料,基于模糊数学综合评价法筛选蓝莓果醋饮料配方,采用GC-MS分析成品饮料和发酵原醋的挥发性香气成分。结果表明：蓝莓果醋饮料的最优配方是蓝莓发酵原醋20%,白砂糖10%,蓝莓汁20%,蜂蜜1%。蓝莓发酵原醋共检测出香气物质44种,包括醇类9种,酯类8种,酸类6种,醛类5种,酚类5种,烃类5种,其余类6种。蓝莓果醋饮料共检出香气物质66种,包括烃类17种,醇类10种,酯类8种,苯类7种,醛类6种,酮类4种,其余类4种。     

Alcohol-free and low-alcohol beers: Aroma chemistry and sensory characteristics

Alcohol-free beers have gained popularity in the last few decades because they provide a healthier alternative to alcoholic beers and can be more widely consumed. Consumers are becoming more aware of the benefits of reducing their alcohol consumption, and this has increased the sales of nonalcoholic alternatives. However, there are still many challenges for the brewing industry to produce an alcohol-free beer that resembles the pleasant fruity flavor and overall sensory experience of regular beers. The aim of this review is to give a comprehensive overview of alcohol-free beer focusing on aroma chemistry. The formation of the most important aroma compounds, such as Strecker aldehydes, higher alcohols, and esters, is reviewed, aiming to outline the gaps in current knowledge. The role of ethanol as a direct and indirect flavor-active compound is examined separately. In parallel, the influence of the most common methods to reduce alcohol content, such as physical (dealcoholization) or biological, on the organoleptic characteristics and consumer perception of the final product, is discussed.     

Influence of hop harvest date of the ‘Mandarina Bavaria’ hop variety on the sensory evaluation of dry‐hopped top‐fermented beer

To impart a special hop aroma to beer, dry‐hopping is a technique that is becoming more and more popular with commercial breweries. Nevertheless, until now little was known about the factors that influence the reproducibility (and consistent product quality) of dry‐hopping with flavour varieties. One factor that could influence the sensory impressions and aroma profile compositions of dry‐hopped beers is the hop harvest date. Therefore, to determine the effects of different harvest dates of the flavour variety ‘Mandarina Bavaria’ on the aroma of top‐fermented beer, laboratory‐scale dry‐hopping trials were performed. Besides tasting sessions of brewed beers, relative quantities of selected hop‐derived, as well as beer‐originated aroma compounds, were investigated by headspace–solid‐phase microextraction–gas chromatography–mass spectrometry. Duo–trio tests between the beers hopped with pellets of different harvest dates showed no significant differences (α = 0.05) between them. In addition, these beers had similar profiles in a five‐point profile tasting scheme. On the other hand, relative concentrations of some hop‐derived aroma compounds – especially myrcene, which is known to be able to contribute to beer flavour – increased corresponding to a later harvest date, while beer originated volatiles were not different between the beers. Analytical results combined with the results of sensory evaluations led to the conclusion that the harvest date of Mandarina Bavaria was not a dominant factor in the dry‐hopping aroma of top‐fermented beers. High amounts of fermentation by‐products are likely responsible for masking effects resulting in no sensory distinctness between the samples with different hop aroma compound concentrations. Copyright © 2016 The Institute of Brewing & Distilling     

Volatile Compounds and the Changes in Their Concentration Levels during Storage in Beers Containing Varying Malt Concentrations

ABSTRACT:  Volatile compounds in beers brewed with different amounts of malt were analyzed by using the stir bar sorptive extraction–gas chromatography-mass spectrometry method. We identified 90 compounds—25 esters, 17 terpenes, 14 alcohols, 11 acids, 6 furans, 6 aroma compounds, 5 carbonyls, and other compounds. An analysis of aged beer suggested that the concentration levels of stale flavor compounds—β-damascenone, γ-nonalactone, ethyl cinnamate, and 2-methoxy-4-vinylphenol—in nonmalt beer were different from those in all-malt and standard beer. Additionally, concentrations of these compounds did not increase during storage in most nonmalt beer analyzed in this study. Nerolidol may be a good marker candidate regardless of the malt content.     

奶啤的研究进展

奶啤是一种以牛乳作为主要原料，经过乳酸菌和酵母菌发酵后所得到的一种含二氧化碳的低醇发酵型乳酸菌饮品。该文系统的介绍了奶啤的发展历程、风味变化、原料组成、发酵过程和工艺流程中的质量控制的现状，对奶啤的未来进行了展望，为奶啤产业的深入研究提供理论参考。