混菌发酵产酶活性与苹果酒风味物质构成的相关性分析

为研究苹果酒发酵过程中酶活性对苹果酒香气品质的影响,对德尔布有孢圆酵母（Torulaspora delbrueckii）和酿酒酵母（Saccharomyces cerevisiae）单独和混菌发酵过程中β-葡萄糖苷酶、果胶酶、酸性蛋白酶及α-淀粉酶活性及苹果酒香气成分进行测定,并通过建立偏最小二乘回归（PLSR）分析模型对苹果酒酒精发酵阶段酶活性与风味物质之间的相关性进行分析。结果表明,混合发酵方式1、2条件下β-葡萄糖苷酶、果胶酶曲线下面积（AUC）最高,分别为15.11 nmol/（min·mL）、19.71 mg/（h·mL）,混合发酵有利于增加苹果酒香气成分的复杂性。相关性分析表明,β-葡萄糖苷酶与27种挥发性物质存在显著相关性（P＜0.05）,果胶酶、蛋白酶与18种挥发性物质存在显著相关性（P＜0.05）,对挥发性物质的形成有较大影响,而α-淀粉酶则与各组分无明显的相关性（P＞0.05）。     

优良本土戴尔有孢圆酵母的筛选及其在冰葡萄酒酿造中的应用

通过测定10株戴尔有孢圆酵母（Torulaspora delbrueckii）（编号为TD1～TD10）对葡萄糖、乙醇、酒石酸、SO2的耐受性能及其产β-葡萄糖苷酶性能,筛选发酵性能良好的戴尔有孢圆酵母,并将筛选菌株与酿酒酵母（Saccharomyces cerevisiae）ST混合发酵冰葡萄汁,最后对冰葡萄酒的基本理化指标进行测定。结果表明,除菌株TD2外,其他菌株均能够耐受葡萄糖500 g/L、乙醇体积分数4%、酒石酸16 g/L及SO2 350 mg/L,其中菌株TD6与TD9产β-葡萄糖苷酶活力较高,为优良本土戴尔有孢圆酵母。将菌株TD6、TD9分别与酿酒酵母ST混合发酵冰葡萄汁时均能在30 d内完成酒精发酵,且冰葡萄酒的基本理化指标均符合国标GB/T 25504—2010《冰葡萄酒》规定。此外,戴尔有孢圆酵母的接种对整个发酵过程的发酵速率与酿酒酵母的生长起到了一定的抑制作用,并且可以降低冰葡萄酒中乙酸和乙醇含量,提高总糖含量。     

白酒酒醅高产酯酵母筛选鉴定及其发酵性能研究

采用平皿培养法从浓香型白酒酒醅中分离酵母,筛选其中具备耐受性良好的产酯酵母,并结合形态学、生理生化试验及26S rDNA分子生物学鉴定筛选酵母,研究筛选酵母与酿酒酵母混合发酵的发酵特性。结果表明,在模拟白酒酿造环境耐受性试验中,3株高产酯酵母均具有一定的耐酸性,且在乙醇浓度为10%时保持较好的生长特性,但在温度为40℃时生长特性均受到抑制,而酵母菌株W5相较其他两株高产酯酵母耐受性能更好,经鉴定为戴尔有孢圆酵母(Torulaspora delbrueckii);在筛选酵母与酿酒酵母模拟白酒发酵试验中,酿酒酵母发酵速率最快,发酵时间为6d;T.delbrueckii W5发酵时间为8d;二者混合发酵时间为9d。在相同的培养条件和发酵条件下,T.delbrueckii纯培养方式下酸度较其他两种培养方式高,其酸度范围为7.62～7.72g/L,说明T.delbrueckii产酸能力很高。但T.delbrueckii W5挥发酸产量较酿酒酵母低,其挥发酸范围为0.32～0.48g/L。另外酿酒酵母纯培养乙醇含量为13.18%～13.50%,说明酿酒酵母相较于T.delbrueckii具有强发酵能力,二者之间混合发酵可以提高T.delbrueckii单独发酵产乙醇能力。可见,戴尔有孢圆酵母虽使发酵时间稍微延长,但产酸和产乙醇能力大大增强,可提高产量和丰富酒香。     

混菌发酵葡萄汁对葡萄糖苷类芳香前体物水解作用的影响

探究非酿酒酵母对葡萄汁中葡萄糖苷类芳香前体物的水解作用,以内蒙古西部地区分离到的具有β-葡萄糖苷酶活性的分属5个属5株酵母菌株为材料,对部分酵母细胞进行胞壁透化处理。随后,采用酿酒酵母（Saccharomyces cerevisiae）单独接种或与非酿酒酵母non-Saccharomyces混合接种的方式进行发酵,探究酿酒酵母与非酿酒酵母混合（1∶1）发酵对发酵进程及发酵液中葡萄糖苷类芳香前体物水解作用的影响。结果表明,除星形假丝酵母（Candida stellata）外,其他3株非酿酒酵母与酿酒酵母混合接种对发酵结果均无明显影响（P＞0.05）,且均可显著降低发酵液中葡萄糖苷类物质的浓度（P＜0.05）,其中尤以萄萄汁有孢汉逊酵母（Hanseniaspora uvarum）及异常毕赤酵母（Pichia anomala）的能力最强,葡萄糖苷类物质的浓度分别为3.04 mmol/L和2.66 mmol/L。     

戴尔有孢圆酵母与酿酒酵母混合发酵对猕猴桃酒香气的影响

用戴尔有孢圆酵母（Torulaspora delbrueckii SY-2-2）和酿酒酵母（Saccharomyces cerevisiae RV002）作为猕猴桃酒发酵菌株,以单接种酿酒酵母、单接种戴尔有孢圆酵母为对照组,同时接种戴尔有孢圆酵母和酿酒酵母、顺序接种戴尔有孢圆酵母和酿酒酵母为实验组,采用顶空固相微萃取法结合气相色谱-质谱技术测定猕猴桃汁发酵酒样产生的挥发性香气成分。结果表明,混菌发酵组获得的挥发性香气成分种类高于单菌发酵组,且顺序接种发酵组的香气成分种类（23 种）和质量浓度（336.95 mg/L）均最高。在顺序接种发酵组中,戴尔有孢圆酵母的参与提高了猕猴桃酒中挥发性物质的种类和含量,特别是苯乙酸乙酯、苯丙酸乙酯、苯乙醇、β-大马士酮、α-松油醇、桉树油醇等物质,赋予猕猴桃酒浓郁的花果香味,丰富了猕猴桃酒的香气成分。香气感官评价表明顺序接种发酵组的花香、草本香、甜香味更加浓郁,酒香和果香次之,整体评分最高。     

不同种属酵母菌对发酵挂面品质的影响研究

利用从传统面食发酵剂中分离并纯化的不同种属酵母菌——酿酒酵母(Saccharomyces cerevisiae)、异常威克汉姆酵母(Wickerhamomycesanomalus)、德尔布有孢圆酵母(Torulaspora delbrueckii)和矮小假丝酵母(Candida humilis)为发酵剂制作发酵挂面，并对挂面的蒸煮品质、质构特性和力学特性等品质进行研究。结果表明：不同种属酵母菌在发酵过程中利用还原糖和产酸的能力差异显著；与未添加酵母菌发酵的挂面相比，添加酵母菌发酵可以改善挂面的蒸煮特性和质构特性，添加矮小假丝酵母菌可降低挂面的蒸煮损失，添加酿酒酵母发酵的挂面硬度显著性降低。综合分析利用酿酒酵母作为发酵剂制作的发酵挂面无论是蒸煮特性还是质构特性等均得到明显改善，具有应用于发酵挂面生产的潜力。     

非酿酒酵母与酿酒酵母混合发酵柿子酒特性的研究

基于非酿酒酵母代谢产物可提升酒的香气和风味物质,将两种非酿酒酵母柠檬形克勒克酵母（Klockera apiculata）和东方伊萨酵母（Issatchenkia orientalis）用于柿子酒发酵,研究两种非酿酒酵母对酒精、二氧化硫、单宁的耐受性和产β-葡萄糖苷酶的能力;对它们分别与酿酒酵母（Saccharomyces cerevisiae）混合发酵柿子酒的特性进行研究。结果表明,东方伊萨酵母在各方面耐受性均优于柠檬形克勒克酵母,但产β-葡萄糖苷酶的能力却较弱;两种非酿酒酵母单菌发酵性能都较弱,东方伊萨酵母单菌发酵结束酒精度为4.51%vol,而柠檬形克勒克酵母单菌发酵酒精度只有3.05%vol;两种非酿酒酵母与酿酒酵母混菌发酵7 d后,酒精度均达到10%vol以上。     

葡萄汁有孢汉逊酵母和酿酒酵母的混合酒精发酵动力学

利用课题组前期优选的具有高β-葡萄糖苷酶活性的葡萄汁有孢汉逊酵母（Hanseniaspora uvarum）研究其与酿酒酵母（Saccharomyces cerevisiae）菌株混合发酵的动力学,为其葡萄酒增香酿造的应用提供理论和技术支持。实验选用陕西杨凌的爱格丽葡萄为原料,设计优选菌株提前酿酒酵母48 h接种和同时接种两个发酵处理,接种量1.0×106 CFU/mL,同时用YPD液体培养基进行两个处理的模拟发酵实验,实验以纯酿酒酵母发酵为对照。发酵过程中监测不同酵母菌数量、酒精体积分数、还原糖等指标,建立动力学模型。结果表明,提前接种处理中优选菌株生存数量最多,生存时间最长,在其对数生长期酒精生成和还原糖消耗速率最慢,但整体酒精发酵正常,酒精生成量不受影响,说明发酵过程中不良副产物生成量有限。因此,优选菌株提前酿酒酵母接种的混合发酵具有葡萄酒增香酿造的应用可能。     

葡萄汁有孢汉逊酵母与酿酒酵母混合发酵对嘎啦苹果酒品质的影响

以嘎啦苹果为实验材料,探究了葡萄汁有孢汉逊酵母（Hanseniaspora uvarum）（云-268）与酿酒酵母（Saccharomyces cerevisiae）混合发酵对苹果酒基本理化指标、酚类物质、香气物质及感官特性的影响。结果表明,相比于酿酒酵母单一发酵,混合发酵苹果酒中乙醇和总酸含量显著降低（P<0.05）,降幅分别为8.72%和9.02%,总酚含量显著增加（P<0.05）,增幅为23.01%;其香气物质种类（36种）明显多于单一发酵苹果酒（31种）,其中香气活度值OAV>1的物质有12种;进一步分析发现,混合发酵苹果酒中具果香味的乙酸酯类和花香味的萜烯类等物质含量显著提高（P<0.05）,具酸腐味的脂肪酸类物质含量显著降低（P<0.05）,对具青草味的C6醇类物质含量影响不大;感官品评结果表明混合发酵苹果酒酒液澄清、禾杆黄色、入口酸度中等偏低,甜度适中,口感平衡,具有丰富的果香味。因此,葡萄汁有孢汉逊酵母与酿酒酵母混合发酵（1:1）能够明显提高苹果酒的品质,增加其发酵香,为低醇果香味的苹果酒酿造奠定了一定的研究基础。     

产α-葡萄糖苷酶抑制剂酵母菌的筛选、发酵条件优化及酶动力学研究

目的：筛选产α-葡萄糖苷酶抑制剂酵母菌,以丰富微生物源α-葡萄糖苷酶抑制剂的来源,开发食用降糖产品。方法：采用4-硝基酚-α-D吡喃葡萄糖苷(p-nitrophenyl-α-D-glucopyranoside,p-NPG)方法从酒糟中筛选产α-葡萄糖苷酶抑制剂能力较强的酵母菌,通过26S rDNA D1/D2区基因序列分析对其进行鉴定,并以α-葡萄糖苷酶抑制率为评价指标,利用单因素试验及正交试验对其进行发酵条件优化。结果：获得1株产α-葡萄糖苷酶抑制剂能力较强的酿酒酵母(Saccharomyces cerevisiae),编号为sg＿093,该菌株产α-葡萄糖苷酶抑制剂最佳发酵条件为以3 g/100 mL葡萄糖为碳源、1 g/100 mL酵母抽提物为氮源、初始p H值为7.0、接种量1.5%、温度20℃下发酵48 h,所得发酵液的α-葡萄糖苷酶抑制率为66.0%,是优化前的1.5倍,并且是以可逆混合竞争方式抑制α-葡萄糖苷酶。结论：获得1株酿酒酵母,其发酵产物对α-葡萄糖苷酶活性有较好的抑制作用。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发，介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.