不同窖龄窖泥微生态变化研究

对泸州老窖不同窖龄的窖底泥与窖壁泥中的微生物变化进行了研究.结果表明:窖壁泥的好氧细菌数量和窖底泥的好氧芽孢细菌数量均随着窖龄的增加呈逐渐降低趋势,而窖壁泥的好氧芽孢细菌数量和窖底泥的好氧细菌数量均随着窖龄的增加呈先降后升的趋势;窖底泥的厌氧细菌和厌氧芽孢细菌以及窖壁泥的厌氧芽袍细菌数量随着窖龄的增加呈逐渐增加的趋势,不同窖龄的窖壁泥的厌氧细菌数量没有明显差异;不同窖龄的窖泥的好氧细菌、好氧芽孢细菌、厌氧细菌以及厌氧芽孢细菌数量总趋势为窖底泥显著高于窖壁泥;不同窖龄的窖泥中的霉菌和酵母菌数量均较少.     

循环利用的封窖泥微生物变化研究

对封窖泥在循环利用过程中微生物变化进行了研究.结果表明,循环利用的封窖泥好氧细菌、好氧芽孢细菌、嫌气厌氧细菌、霉菌、酵母菌以及放线菌数量随封窖排次的增加而逐渐降低,使用5排的封窖泥的好氧细菌、好氧芽孢细菌、嫌气厌氧细菌、霉菌数量较起始泥分别降低6.12倍、1.35倍、8.58倍和4.2倍,而嫌气厌氧芽孢细菌数量则是随着封窖泥使用排次的增加而逐渐增加,使用5排的封窖泥的嫌气厌氧芽孢细菌数量是起始泥的1.75倍;循环利用不同排次的封窖泥细菌类群有较大差异,而霉菌、酵母以及放线菌差异不大.     

浓香型酒建窖窖泥厚度与微生物菌种群的关系研究

对浓香型酒建窖窖泥厚度与微生物菌种群的关系进行了研究,结果表明：窖壁泥的好氧细菌和好氧芽孢细菌数量为150mm厚度窖泥〉50mm厚度窖泥〉100mm厚度窖泥,厌氧细菌和厌氧芽孢细菌数量随着建窖窖泥厚度的增加呈逐渐增加趋势;而窖底泥的好氧细菌和好氧芽孢细菌数量则随着窖泥厚度的增加呈逐渐减少趋势,厌氧细菌和厌氧芽孢细菌数量与窖泥厚度没有相关性,不同厚度窖泥的霉菌和酵母菌数量均较少。     

浓香型酒人工窖泥酿造过程中微生物变化研究

对浓香型酒人工窖泥酿造过程中微生物变化进行了研究。结果表明:4个处理的人工窖泥酿造1轮的窖壁泥,其好氧细菌、好氧芽胞细菌、厌氧细菌、厌氧芽胞细菌数量均较建窖起始泥有大幅度的增加,以后随着酿造轮次的增加呈逐渐降低趋势,霉菌和酵母菌数量在酿造过程中均较少;窖底泥的好氧细菌、好氧芽胞细菌、厌氧细菌以及厌氧芽胞细菌均明显高于窖壁泥,分别是窖壁泥的2.44倍、1.66倍、3.15倍和3.67倍。     

高水分固态发酵上部烟叶对其微生物量和化学成分的影响

研究了高水分固态发酵上部烟叶过程中烟叶微生物数量和化学成分的变化。结果表明:在高水分、常温好氧发酵中,烟叶发酵到第二三天开始发霉,发酵被迫终止。发酵过程中好氧细菌逐渐减少,酵母和霉菌大量繁殖;高水分、常温厌氧发酵过程中,厌氧细菌小幅度减少,酵母数量发酵前期迅速增加,发酵到第4天后数量趋于稳定;高水分、高温好氧和厌氧发酵过程中,酵母和霉菌不再生长,好氧细菌和厌氧细菌均大幅度减少;在这4种发酵方式中,烟叶淀粉和蛋白质的含量均随着发酵时间的延长而逐渐降低。     

太白酒发酵过程中酒醅微生物区系分析

以太白酒厂秋季正常生产窖池为试验窖。对窖池酒醅的微生物区系进行分析。研究凤香型白酒发酵过程中酒醅微生物区系的多样性、构成及演替呈动态消长的变化趋势。结果表明。发酵4d时上中层酒醅中的酵母菌、霉菌、放线菌增殖迅速;发酵7d后,好氧细菌和芽孢菌急剧增殖,酵母菌、霉菌、放线菌急剧减少;发酵18d以后,酵母菌、好氧细菌和霉菌均急剧减少,芽孢菌的数量相对增加。     

基于基因测序技术对辣椒酱生产设备和空气中的细菌检测

为进一步阐明辣椒酱中产气细菌的来源和引入阶段,采用传统培养基培养方法和16S r DNA测序方法对存在产气现象的辣椒酱生产设备和空气中的细菌菌群种类和含量进行了分析。结果从辣椒酱生产设备和车间空气中分离到6种好氧细菌和16种厌氧细菌。在原料仓库、炒制间和包装间空气中好氧细菌菌群密度分别为3. 0×10~2、1. 3×10~4、8. 2×10~2CFU/m~3,而厌氧细菌菌群密度分别为1. 4×10~3、3. 4×10~3、7. 0×10~1CFU/m~3;设备中好氧菌菌群密度分别为:1. 4×10~5、7. 6×10~5、3. 6×10~7CFU/g,而厌氧细菌菌群密度分别为2. 1×10~5、8. 7×10~5、7. 4×10~7CFU/g。设备中好氧菌群密度为:经过16S rDNA测序鉴定,芽孢杆菌属细菌在各工段中均占明显优势。在3个生产工段好氧细菌中产芽孢菌占比分别为52. 31%、80. 23%、100. 00%,而在厌氧细菌中产芽孢菌占比分别为28. 69%、80. 23%、65. 00%。综合细菌种类和总数,结论为传统加热灭菌无法有效杀灭产芽孢菌,同时包装线具有二次污染隐患。     

绿衣观音土曲培养过程中微生物及酶系的动态变化

通过对绿衣观音土曲中微生物总数进行平板计数以及相关酶类进行跟踪检测,并结合分子生物学方法对分离获得的菌株进行鉴定,分析绿衣观音土曲培养过程中微生物及相关酶类的变化规律。结果表明,观音土曲培养过程中细菌数量最多,霉菌最少。酵母数量呈逐步上升趋势,培养后期数量达到峰值;细菌数量先上升后下降,在培养中期数量达到峰值;霉菌数量在培养后期最多。共分离鉴定出酵母8种、霉菌7种、好氧细菌7种和乳酸菌5种,酵母分别是酿酒酵母、异常威克汉姆酵母、库德里阿兹威毕赤酵母和扣囊复膜酵母等;霉菌主要为曲霉属、米根霉和毛霉等;细菌以芽孢杆菌和乳杆菌为主。糖化酶酶活最高,其次为淀粉酶,酸性蛋白酶酶活最低,3种酶活力均呈先下降后上升的趋势。     

细菌在纸厂废水净化生物硫循环中的作用

论述了厌氧和好氧硫转化过程中细菌的作用和用途,并以纸厂处理废水为例进行说明。含硫酸盐的废水首先通过升流式厌氧污泥床（UASB）反应器去除大部分COD,此时会生成生物气。在好氧池中,去除残余的COD和溶解的H2S。这些生物气中包含CH4（80%～90%）、CO2（10%～20%）和H2S（0.8%～1.2%）,生物气脱硫后在能量发生器中燃烧,进而需要一种新的生物方法以去除H2S。厌氧生物反应器中的生物质呈紧密的颗粒状结构,含有多种微生物群。文中也将其他类型的厌氧生物反应器与UASB作了比较。     

窖泥微生物与酒体质量的关联性分析

以宋河不同窖龄窖池及各窖池所产原酒为实验材料,针对窖池窖泥中各种微生物的含量以及分布对酒质的影响进行分析探讨。研究结果可以看出随着窖池窖龄的增加,窖池酵母菌含量、细菌含量和放线菌含量均有所提高,且同一窖龄窖池酵母菌和放线菌含量窖池池壁多于窖池底部,细菌含量窖池池壁少于窖池底部;霉菌在窖池中含量相对较少,且随窖池窖龄变化其含量变化不明显;好氧芽孢菌和厌氧芽孢菌,窖池池底和窖池池壁含量均随窖池窖龄增长而增高,且厌氧芽孢菌随窖龄增长速率快于好氧芽孢菌,同一窖龄窖池好氧芽孢菌含量窖池池壁多于窖池池底,同一窖龄窖池厌氧芽孢菌含量窖池池壁少于窖池池底;除霉菌外其他菌种均与窖池窖龄呈显著正相关性。经感官评定和气相色谱分析,不同窖龄窖池所产原酒质量随着窖池窖龄的增加显著提升。     

Sequential anaerobic-aerobic treatment of soil contaminated with weathered Aroclor 1260

Soil contaminated with weathered Aroclor 1260 was bioremediated by sequential anaerobic and aerobic laboratory-scale treatment. The initial concentration was 59 microg of PCBs/g of soil. Following 4 months of anaerobic treatment with an enrichment culture, all of the major components in Aroclor 1260 were completely or partially transformed to less chlorinated PCB congeners. The major products of reductive dechlorination were 24-24-tetrachlorobiphenyl and 24-26-tetrachlorobiphenyl, and the average chlorine substituents per PCB molecule decreased from 6.4 to 5.2. The molar concentration of PCBs did not decrease during the anaerobic treatment. All of the major products formed during the anaerobic treatmentwere degraded in the subsequent aerobic treatment using Burkholderia sp. strain LB400. After 28 days of the aerobic treatment, the concentration of PCBs was reduced to 20 ug/g of soil. PCBs were not significantly removed in aerobic treatments unless they were bioaugmented with LB400. Also, PCB degradation was not detected in soil bioaugmented with LB400 without prior anaerobic treatment. These results confirm the potential for extensive biological destruction of highly chlorinated, weathered PCB congeners in soil.     

不同空气暴露条件下四川泡菜的品质变化及产植物细胞壁降解酶微生物分析

以四川泡菜为研究对象,通过发酵坛口暴露、间歇暴露和封闭三种空气暴露程度模拟不同的空气暴露情况,探究不同空气暴露条件下四川泡菜发酵过程中的品质变化,并分析产植物细胞壁降解酶(Plant cell wall degradation enzymes,PCWDEs)的主要微生物种类。结果表明:发酵8 d后不同空气暴露条件下四川泡菜都具有该条件下的最佳质构,发酵前16 d,三种条件下四川泡菜的pH都迅速下降至3.0,总菌和乳酸菌数量都呈现先上升后下降的趋势。随着发酵时间的增加,不同空气暴露条件下四川泡菜的品质出现差异,发酵64 d后暴露式发酵四川泡菜的pH上升至6.5,真菌数量上升至7.6 lg CFU/mL,和发酵8 d相比泡菜硬度和脆度分别下降了93.2%和100%,泡菜发生明显软腐,在该条件下分离得到的19株(其中有12株为发酵48 d时分离得到)产PCWDEs微生物多为好氧型微生物;间歇暴露式发酵四川泡菜在发酵64 d后pH上升至3.5,和发酵8 d相比泡菜硬度和脆度分别下降了39.1%和35.6%,泡菜出现轻微腐败,在该条件下分离得到的6株产PCWDEs微生物多为好氧型微生物;封闭式发酵四川泡菜在发酵64 d后pH仍维持在3.0,乳酸菌数量虽下降至5.34 lg CFU/mL,但仍是四川泡菜中的主导微生物,和发酵8 d相比泡菜硬度和脆度分别下降了52.5%和24.4%,在该条件下分离得到的5株产PCWDEs微生物多为兼性厌氧型微生物。     

Chemical studies with silage microorganisms in artificial media and sterile herbages

The fermentation changes in artificial media and in sterile herbages inoculated with strains of yeast, hetero-and homo-fermentative lactic acid bacteria isolated from silage were studied in two experiments. In the first, using malt extract broth, four treatments were employed: aerobic, high level of glucose; aerobic, low level of glucose; anaerobic, high level of glucose; anaerobic, low level of glucose. The pH decreased in all cultures. There were no appreciable differences in pH among the cultures of the heterofermentative lactic acid bacterium, but in the cultures of the homofermentative organism there was a greater decrease in pH aerobically than anaerobically. The lowest pH values in the yeast cultures, occurred in the high glucose treatments both aerobically and anaerobically. In all the yeast cultures, acetic, propionic, butyric, isobutyric and isovaleric acids were present. The heterofermentative lactic acid bacterium produced only acetic acid, the greatest amount occurring under aerobic conditions. Ethanol was detected in the culture of the heterofermentative lactic acid bacterium but not in that of the homofermentative organism. Relatively large amounts of i-pentanol were found in the aerobic yeast cultures. In the second experiment, inoculated grass was ensiled with similar treatments to those used in the first experiment. Two incubation periods, 3d and 10d were used. The pH values in all treatments were high (> pH 5.0). In aerobic conditions, the lactic acid contents after the 10d incubation were higher than after 3d. The losses of water soluble carbohydrates during fermentation were greater in the aerobic than anaerobic treatments. Acetic acid was present in all cultures but the higher volatile fatty acids (C₃-iC₅) were only detected in appreciable amounts in the aerobically treated herbages after 10d. In addition to ethanol, n-propanol and i-butanol were also present in all the 10d anaerobic treatments. i-Pentanol occurred in both the aerobic and anaerobic treated herbages.     

Lactic Acid Concentration and Microbial Spoilage in Anaerobically and Aerobically Stored Ground Beef

Lactic acid concentration of coarsely ground beef, packaged in low oxygen permeability casings, is inversely related to sensory acceptability of the meat following regrinding and aerobic storage for six additional days. Samples, reground and stored aerobically after periods of anaerobic storage, were assayed for total aerobic bacterial counts, percentage of gram-positive microflora, and pH. Lactic acid concentration ranged from 130 to 1055 mg per 100g ground beef and increased with anaerobic storage. During 6 days of aerobic storage, both increases and decreases in concentration were noted and related to changes in microbial flora. A positive correlation was found between the proportion of gram-positive bacteria (lactic acid bacteria) and lactic acid and pH.     

盐度对鱼露贮存过程中品质的影响

以高盐鱼露为研究对象,研究高盐度鱼露贮存过程菌落总数的变化情况以及不同盐度对鱼露品质的影响。结果表明,潮汕鱼露在存放期间,随着存放时间延长菌落总数逐渐减少,不同等级的鱼露产品在30 d内也存在同样现象。高盐浓度对鱼露的菌落生长的抑制作用效果显著,氨基酸态氮含量不同的鱼露,其对高盐抑菌效果无明显影响。鱼露存放15 d和30 d时,25%盐度的菌落总数较10%时分别降低了97.91%和99.73%,表明25%盐都对控制鱼露微生物指标和有关感官指标合格均有明显的贡献。     

传统咸干鲅鱼自然风干过程细菌菌群变化

目的 揭示咸干鲅鱼自然风干过程中细菌群落结构的变化规律。方法 采用高通量测序技术对新鲜鲅鱼以及风干2、4、6、8、12 d的鲅鱼样品中的细菌种类及其丰度进行分析。结果 新鲜鲅鱼中发光杆菌属（Photobacterium）、嗜冷单胞菌属（Psychrobacter）、交替假单胞菌属（Pseudoalteromonas）和黄杆菌属（Flavobacterium）所占比例较高,是新鲜鲅鱼的优势菌;风干过程中,Psychrobacter、Flavobacterium比例迅速减少;Pseudoalteromonas在风干前期比例增加,4 d后比例逐渐减少;Photobacterium在风干前2 d比例降低,之后比例迅速增加,12 d时比例高达80%,是传统咸干鲅鱼的优势菌属。鲅鱼风干过程微生物种类趋向简单化,菌群功能主要聚焦在化能异养、有氧异养和发酵,其中化能异养、有氧异养对应的丰度相对稳定,而发酵对应的丰度在风干后期呈增加趋势。胁迫耐受、兼性厌氧、运动性等表型丰度增加,好氧对应的丰度降低,这与风干后期发酵功能对应的丰度增加的现象一致。结论 高通量测序的结果可以更加全面的反映咸干鲅鱼风干过程中细菌种类及其丰度变化,这为进一步了解传统水产制品中的未可培养微生物、优化加工工艺提供了参考。     

植物乳杆菌接种量对低盐风干肠品质特性及风味特征的影响

探究不同接种量105、106、107 CFU/g（LP5、LP6、LP7）的植物乳杆菌对低盐风干肠品质特性及风味特征的影响。以低盐风干肠（食盐质量分数为1.75%）为对照组，在发酵第0、3、6、9天对4 组风干肠的pH值、水分含量、水分活度、剪切力、乳酸菌数和肠杆菌数进行测定；采用电子鼻与气相色谱-质谱技术，对第9天样品的风味特征进行分析。结果表明，随着发酵的进行，各处理组的水分含量和水分活度逐渐降低，剪切力逐渐上升；发酵结束时（第9天），所有处理组中LP6和LP7的水分含量和水分活度较高，LP7的肠杆菌数最低，各处理组的剪切力无显著差异（P＞0.05）。随着植物乳杆菌接种量的增加，低盐风干肠的pH值逐渐下降（除发酵第0天），乳酸菌数逐渐上升（除发酵第6天）。接种植物乳杆菌增加了酸和酯类物质整体含量，不同接种量低盐风干肠挥发性风味差异明显。结合感官评价结果确定接种量106 CFU/g的低盐风干肠的总体可接受性最佳，咸味酸味适中。     

培养条件对食品中乳酸菌检验结果的影响

对市售四种不同的乳酸菌饮品,分别采用3种不同厂家的MRS培养基,在厌氧和常规需氧的条件下培养,得出乳酸菌的计数结果,并进行差异性分析和产生差异原因的探究.结果表明:三种培养基的计数结果存在显著性差异(P<0.05),两种培养条件下的计数结果也有一定的差异,但并不显著(P>0.05),厌氧条件下计数结果较高.样品中添加乳...