浓香型白酒在工业生产过程中微量成分的变化规律研究

以四川某名优酒厂浓香型白酒生产车间的6口窖池为对象,分析浓香型白酒在发酵和贮存过程中微量成分的变化特征,探索浓香型白酒在发酵和贮存过程中香气成分的变化规律,为进一步了解浓香型白酒的发酵机理提供理论依据.     

传统浓香型白酒窖池发酵糟醅研究现状及其展望

传统的浓香型白酒生产是以泥窖为发酵载体,窖池中的酒醅在一定的条件下经过各种微生物以及酶的作用,进行复杂的能量代谢,最终将淀粉类大分子物质转化为酒精和各种香味物质,形成了浓香型白酒独特的风格。以浓香型白酒为出发点,论述了近年来人们对浓香型白酒发酵过程中微生物、理化指标、香味物质的研究状况,并进行了分析和展望。     

浓香型白酒酒醅风味物质和微生物菌群结构随发酵时间的变化规律

为解析浓香型白酒发酵周期与原酒品质的关系,跟踪了发酵周期长达5个月的窖池,并重点关注了窖池下层酒醅中主要风味物质和微生物菌群的动态变化。研究发现酒醅中的乳酸、乙酸在发酵初期(0～14 d)迅速增加,之后增速放缓;己酸、丁酸以及己酸乙酯含量则随发酵时间的延长逐渐增加。整个发酵过程中,乳杆菌科占绝对优势,随着发酵时间的延长,酒醅中瘤胃菌科(Ruminococcaceae)和梭菌科(Clostridiaceae_1)微生物的相对丰度逐渐上升,这些微生物也是窖泥中的高丰度微生物。结果表明,在长期发酵过程中,窖泥为酒醅持续不断地提供其主体的厌氧微生物。相关性分析进一步表明,这些微生物对发酵后期己酸、丁酸、乙酸的合成具有重要贡献。虽然窖泥来源的微生物在酒醅微生物中占比较低,但对于浓香型白酒的贡献却非常巨大。该研究为从发酵角度控制浓香型原酒品质提供了重要参考。     

浓香型白酒发酵过程中酒醅的微生物区系分析

为了比较准确地把握浓香型白酒发酵过程中酒醅微生物区系的多样性及消长规律 ,以全兴酒厂正常生产窖池为试验窖 ,采用特制取样器跟踪发酵过程取样 ,对窖池酒醅中不同空间位置的微生物区系进行了动态分析 ,初步弄清了浓香型白酒窖池酒醅不同层面、不同区域微生物数量的分布及变化趋势 ,并通过形态、生理学特性的分析比较以及 16SrDNA、18SrDNA序列分析等 ,对发酵过程中主要微生物类群进行了分类鉴定     

温度控制下浓香型白酒窖池温度变化及酵母数量变化趋势研究

利用换热装置控制浓香型白酒窖池发酵温度;在维持中后期窖池顶温的措施下,通过对正常发酵与控温发酵窖池酵母数量变化监测,探讨发酵温度对窖池微生物区系结构组成的影响和对白酒固态厌氧发酵的作用机制。结果显示:控温措施作用明显;温度变化对酵母数量影响显著。     

三井窖池微生物和理化参数的变化研究

为了探讨浓香型白酒发酵过程中的微生物消长、物质变化和温度变化三者之间的关系,以三井酒业五粮车间正常发酵的窖池为试验窖池,分别对每个窖池的微生物、物质变化和温度进行跟踪。结果表明：微生物的大量繁殖会导致温度升高以及理化指标的变化;温度变化和微生物的消长有同步现象;酸度和酒精度的升高会导致部分微生物数量的下降。     

浓香型白酒窖池中糟醅微生物的变化趋势研究

研究了浓香型白酒典型微生物菌群主导的发酵动态变化过程。通过对窖池典型微生物菌群的数量变化监测,发现酒精发酵与生酸产酯发酵并未有明显界限,随着窖池主导菌群,或窖池微生物区系的交替演变而逐步转换。同时,不同区域企业生产窖池的典型微生物菌群的数量变化有差异;单纯用牛肉膏蛋白胨培养基结合平板涂布计数法测定好氧细菌数量,不能真实反映窖内好氧细菌的真实情况。     

窖池对浓香型大曲白酒生产的影响

窖池是浓香型大曲白酒生产的发酵容器,关键在于窖泥的选择、培养,窖泥中长年富集了经长期驯化的种类和数量繁多的有益酿酒微生物,为生产出优质浓香型大曲白酒提供了先决前提条件。企业均把养护好窖池当成生产的头等大事来抓,以提高产品质量和优质品率。     

浓香型白酒生态洞酿糟醅中微生物的变化研究

本项目利用黄鹤楼酒生态洞酿车间,探索其区别于其他传统白酒生产的独特之处。研究了不同季节浓香型白酒典型微生物菌群在整个发酵周期的动态变化,通过平板计数法对春夏秋冬4个季节窖池典型微生物菌群数量进行动态监测,比对在相同生产工艺条件下,酿造浓香型白酒发酵过程中糟醅微生物(酵母菌、细菌、霉菌)的数量变化,为黄鹤楼生态洞酿基酒产质量在不同季节的稳定性提供依据。     

浓香型白酒容器及窖池发酵糟醅动态因子变化及白酒品质研究

对浓香型白酒糟醅进行容器和窖池发酵,并对发酵糟醅的常规理化指标、微生物指标、主要香气成分、白酒品质进行对比分析,探讨窖外发酵的可能性。结果表明,容器和窖池发酵糟醅的可培养好氧细菌、酵母和霉菌、温度、水分、酸度、还原糖、淀粉、酒精度、四大酯、三大酸在发酵过程中变化趋势基本相同,均呈先增加后降低的趋势;除己酸乙酯含量差异较大外,其余物质含量差异不大,窖池发酵糟醅己酸乙酯最大值为0.13 g/L,容器发酵糟醅为0.11 g/L。窖池和容器发酵糟醅酒精度在25 d均达峰值,分别为6.7%vol、6.0%vol。窖池发酵二段酒的感官评价优于容器发酵酒,但容器发酵酒的大多数香气成分含量稍高于窖池发酵酒,特别是己酸乙酯含量为窖池发酵酒醅的1.4倍,但二者都能体现浓香型白酒风格。因此,进行窖外容器发酵是可行的。     

Changes in smoking prevalence in Ukraine in 2001-5

Objectives

To analyse trends in smoking prevalence in Ukraine from three surveys conducted in 2001–5, and to explore correlates of observed changes, in order to estimate the stage of tobacco epidemic in Ukraine.

Design

Repeated national interview surveys in Ukraine in 2001, 2002 and 2005.

Main outcome measure

Prevalence of current smoking among the population aged ⩾15 years.

Results

The age‐standardised prevalence of current smoking in Ukrainian men was 54.8% in 2001 and 66.8% in 2005. Among Ukrainian women, prevalence increased from 11.5% in 2001 to 20.0% in 2005. ORs for yearly increase in prevalence were estimated as 1.164 (95% CI 1.111 to 1.220) for men and 1.187 (1.124 to 1.253) for women, which implies that, on average, 3–4% of men and 1.5–2% of women living in Ukraine join the smoking population each year.

Conclusions

In Ukraine, smoking prevalence is increasing in most population groups. Among men, the medium deprivation group with secondary education has the highest smoking prevalence. Among women, while the most educated, young and those living in larger cities are the leading group for tobacco use, other groups are also increasing their tobacco use. Tobacco promotion efforts appear to have been significantly more effective in Ukraine than smoking control efforts. The decrease in real cigarette prices in Ukraine in 2001–5 could be the main factor explaining the recent growth in smoking prevalence.Ukraine is a large eastern European country with high smoking prevalence. Tobacco products are widely available at very low prices, and the transnational tobacco industry is extremely successful in promoting its products and lobbying for its interests in the legislative field. Advocacy of tobacco control has only recently achieved some success in the legislative field, with the first tobacco control law being adopted in late 2005. Ukraine ratified the Framework Convention on Tobacco Control in 2006, but there is still much cause for concern regarding the enforcement and effectiveness of the adopted legislative measures. Unfortunately, the government is not yet involved in nationwide surveillance of the tobacco problem, and the available data have mostly been gathered with funding from foreign donors. Several attempts have been made to measure the extent of the tobacco epidemic in the countries of the former Soviet Union (FSU).^{1,2,3,4,5,6,7} Most of these studies have shown rather high smoking prevalence among men (50–70%) and comparatively low prevalence among women (5–20%). Most countries in the FSU have similar smoking rates, while certain trends are shown to be related to the differences in how the transnational tobacco industry succeeds in every national tobacco market.⁶ Unfortunately, few studies have been published showing trends in smoking prevalence in the FSU.⁷ In Ukraine, two studies^3,4 provided point estimates of smoking prevalence.The aim of this study was to analyse trends in smoking prevalence in Ukraine, on the basis of three surveys conducted in 2001–5, and to explore correlates of observed changes in order to estimate the stage of the tobacco epidemic in Ukraine.     

2010年河南省部分食品中重金属污染状况分析

了解河南省部分食品中重金属污染的现状。方法 在河南省18个省辖市采集8大类3 657份食品样品,按照国家标准检测食品中铅、镉和汞的含量,检测结果按照GB 2762—2012《食品安全国家标准食品中污染物限量》进行评价。结果 河南省部分食品中铅含量的平均值为0.34 mg/kg,总体超标率为8.8%(320/3 656),其中粮食、肉类和蔬菜中超标率较高,分别为17.2%(95/552)、14.5%(85/587)和10.7%(57/534);部分食品中镉含量的平均值为0.054 mg/kg,总体超标率为3.9%(143/3 657),其中食用菌和蛋类中超标率较高,分别为9.6%(49/508)和8.1%(42/518);部分食品中汞含量的平均值为0.077 mg/kg,总体超标率为8.3%(303/3 657),其中蔬菜和粮食中超标率较高,分别为25.3%(135/534)和12.3%(68/551)。结论 河南省部分食品中铅、汞污染情况较为严重,其中粮食、蔬菜和肉类食品中污染情况尤为突出,需要加强监管。     

Content of selenium in fishes,caught in lakes in Buriatia

Study of selenium accumulation by fish of Buryatia shows relatively high accumulation level for the Baikal lake (213-513 mcg/kg) contrary to the lakes of Baunt and Selenginsk regions of the republic (84-227 mcg/kg). Selenium deficiency in Baunt region is also confirmed by low selenium levels in meat of native origin (39-95 mcg/kg). Among different tissues and organs the lowest selenium levels are typical for muscles, the value increasing in the row: muscle < skin < air bladder < scales < fin < liver < roe.     

Moulds and mycotoxins in sorghum stored in traditional containers in India

Various traditional containers have been used in India for storage of sorghum grains. Sorghum is susceptible to fungal infestation and toxin elaboration. The present study relates to the mould and mycotoxin contamination (aflatoxin B₁ and T-2 toxin) in stored sorghum in different storage containers viz. “Kotlu” (Storage rooms), earthenware pots, gunny bags and reed baskets. Aspergillus sp. and Fusarium sp. were the prominent genera and the “Kotlu” form of storage was most susceptible to fungal attack. Storage treatment had little effect on fungal contamination, but despite the fungal infestation, the mycotoxin contamination was found to be very low.     

中国固态发酵白酒中功能细菌研究进展

细菌是白酒酿造3大类微生物之一,其在白酒生产中有着重要的作用,如:芽孢杆菌、乳酸菌、放线菌和梭菌等,它们能产生酯类、有机酸、吡嗪、萜烯等微量成分,从而影响白酒的风味与品质。基于细菌在白酒中的重要功能以及微生物分离培养技术和分析检测技术的进步,近年来相关研究越来越深入。该文综述了近年来白酒功能细菌的研究进展,介绍了酿酒各个环节中主要功能细菌及其在白酒中的作用,旨在为白酒功能细菌的研究提供参考。