提高固态发酵食醋出品率的实用技术

介绍了固态发酵食醋生产中，从优选原辅料，改进处理方法，强化双边发酵酶系，液态酒精发酵，纯种醋酸发酵等方面，采取提高食醋出品率的实用技术。     

豆豉中生物胺含量的动态变化研究

采用高效液相色谱法对豆豉中生物胺含量进行动态检测。结果表明,纯种强化发酵和自然发酵豆豉样品中均检测出色胺、苯乙胺、腐胺、尸胺、组胺、酪胺、亚精胺和精胺。纯种强化发酵条件下生物胺总含量在前、后发酵时期都呈先上升后下降的趋势,而自然发酵条件下均呈缓慢上升趋势,且前发酵总生物胺含量高于后发酵时期。两种发酵条件下,酪胺和亚精胺为主要生物胺,苯乙胺存在纯种发酵中。纯种强化发酵豆豉总生物胺含量高于自然发酵,酪胺和苯乙胺的含量分别高出2倍和4倍,与生产环境中粪肠球菌的污染关联性较大。豆豉发酵过程和成品中总生物胺含量均＜250 mg/kg,短期内不存在食品安全问题。     

高溶栓活性豆豉固态发酵工艺的响应面优化

利用浅盘固态发酵技术对豆豉纤溶酶出发菌株进行固态发酵。固态发酵培养基经灭菌、添加碳源等操作后,按一定比例接种种子液,在合适的发酵条件下进行固态纯种发酵。通过单因素试验确定出了对固态发酵过程影响显著的过程参数,应用SAS软件响应面分析程序,分别对发酵过程中的接种量、发酵周期、发酵温度、大豆初始水分含量等过程参数进行了分析与优化。试验得出了豆豉纤溶酶出发菌株固态发酵的最优工艺参数,即大豆水分含量300%、发酵周期72h、发酵温度39℃,在此条件下最大发酵酶活可达到665.6IU/mL。     

一株醋酸菌液态扩大培养及应用于固态发酵酿醋研究

文章以保宁醋固态发酵醋醅中筛选出的一株醋酸菌为试验菌株,对该菌株液态扩大培养方式、培养基及应用于固态发酵酿醋进行了研究。结果表明:以酒精质量分数1%的米酒为培养基,摇床培养,醋酸菌生物量可达7×107 cfu。固态发酵酿醋对照组最终醅酸为3.2g/dL,强化组最终醅酸达3.94g/dL,混合原料出醋率强化组较对照组提高100%。     

拟青霉固态发酵代谢产物分析

从茅台酒生产环境中分离纯化得到1株霉菌MTDF-01,经该菌的18S rDNA测序比对,最终确定该菌株为拟青霉。将该菌在制曲工艺、堆积工艺以及兼性条件下分别进行纯种固态发酵,利用GC-MS对其代谢物检测解析。结果表明,纯种固态发酵能代谢生成酸、醇、醛、酮、酯及芳香族化合物等多种物质。这些物质中有多种是食品中的风味物质和风味前体物质,亦是茅台酒众多呈香呈味物质中的组成部分。     

大规模培养红曲霉产生生理活性物质的研究

研究了红曲大规模培养产生生理活性物质的方法及定性、定量测定该活性物质的方法，其中以Monascus,ruber为菌种，用新鲜的粳米及添加一定的敖皮为固体发酵培养基，采用二级放大培养，用大三角瓶及大盘作发酵容器，获得纯红曲制品，在大规模固态发酵培养过程中应注意的事项，同时采用建立无菌净化间进行大规模红曲培养的可行性的研究。     

基于物联网在线监测白酒固态发酵实验装置的设计与实现

在白酒酿酒实验过程中，通常使用受外部影响较小且所需原辅料用量较少的固态发酵设备，以模拟白酒固态发酵过程，同时采集发酵过程中的相关指标。分析与探讨了一种基于物联网在线监测的白酒固态发酵实验装置，该装置包括发酵装置、取样装置、保温装置、物联网在线监测系统等部分。其中，发酵装置由桶体、桶盖、排气孔、篦子板、黄浆水收集仓、排水口1、取样孔等部分组成，保温装置由加热水箱、输送水管、水泵、进水口、排水口2、保温夹层等部分组成，物联网在线监测系统由检测器和物联网监测系统组成。该装置能最大程度模拟白酒固态发酵，同时能够及时对发酵过程中的水分、酸度、温度和二氧化碳排放量等数据进行收集。该装置设计合理，符合设备安全要求，可以满足白酒固态发酵的工艺要求。     

地衣芽孢杆菌固态发酵代谢产物分析

从茅台酒生产环境中分离纯化得到1株细菌MTDB-02,经16S rDNA测序比对,最终将MTDB-02定性为地衣芽孢杆菌。将该菌在制曲工艺、堆积工艺以及兼性条件下分别进行纯种固态发酵,利用GC-MS对其代谢物进行检测解析。结果表明,该菌纯种固态发酵能代谢产生70多种物质。这些物质中有多种是食品中的风味物质和风味前体物质,亦是茅台酒呈香呈味物质中的一个组成部分。     

回渣酿醋工艺

我国食醋的酿造方法，大致可分为固态发酵与液态发酵两大类，以固态发酵法较为普遍。固态发酵的醋醅疏松，酷中水分基本上包含于基质颗粒之中，具有较大的气相和固相界面，能溶存一定量的空气，对醋酸菌等好气性微生物的生长代谢极为有利，发酵周期较传统液态发酵法短。研究表明，同一种微生物生活在同一柜内，与生活在两个不同态的接触面上，其代谢产物明显不同，如把汉逊氏酵母接种在加人大量玻璃丝，使之成为半固相的米曲汁中培养96h，所产生的乙酸乙酯比在同一相内高二倍左右。固态发酵具有气相和固相两个不同态的接触面，代谢产物酯类…     

济南瑞丰生物工程有限公司 酿酒微生物专业制造商、省级高新技术企业

<正>复合酯化酶本产品采用紫红曲霉(Monascus purpureus)菌种,经过耐酸诱变,获得高产酯化酶优良菌株,通过纯种液态补料通风培养,除掉菌丝,获得法酵液,并通过保活造粒、低温脱水等工艺制成。具有提高浓香型白酒己酸乙醅含量及各种香味成分,强化浓香型固态发酵白酒特征香气的功能。单独使用该产品,建议使用量0.5%,原酒中己酸乙酯可以提高80 mg/100 mL以上。     

固态发酵过程中气体传质控制策略的研究进展

固态发酵在一些生物制品的生产及生物处理过程中具有明显的优势,特别是近年来随着对固态发酵理论模型和发酵设备的研究不断深入,固态发酵的应用范围越来越广。对于好氧的固态发酵来说,氧气的传质效率低仍然是工艺优化和提高产量的主要限制因素,同时它也影响了固态发酵生产规模的扩大。该文分析了固态发酵过程中气体传质的原理及过程,并对此提出了一些提高固态发酵过程中气体传质效率的策略,如控制固体基质特性、选择合适的搅拌通风方式等,最后展望了固态发酵技术的发展前景。     

A novel industrial-level reactor with two dynamic changes of air for solid-state fermentation

A novel industrial-level solid-state reactor (70 m3) with two dynamic changes of air was designed and has been put into operation successfully, in which the unite of virulence of Bacillus thuringiensis produced is maintained above 18,000 IU/mg. Two dynamic changes of air (including air pressure pulsation and internal circulation) in the fermentor can increase mass and heat transfers, as well as improve the porosity within the substrate. The reactor is novel and of significance in exploiting numerous socioeconomic advantages of solid-state fermentation.     

Improving porous crumb structure of rice‐related leavened food products by fermentation and gelatinization at slightly higher air pressure conditions

Porous crumb structure of rice‐related leavened food products developed under air pressure conditions during fermentation and gelatinization in a fabricated fermentation chamber were characterized. Therein, four samples were prepared under three pressurized conditions (sample pressurized by the leavened gas itself, 1 kg/cm² initial pressure, 1.5 kg/cm² initial pressure) along with a control (unpressurized). Crumb volume, specific volume, bulk density, pH as well as crumb texture profile and cellular structure were analyzed. Results revealed that fermentation and gelatinization under air pressure (slightly higher than the atmospheric air pressure) conditions in the fabricated fermentation chamber help to arrest leavening gas within the dough mass to improve the properties of porous crumb structure. Sample fermented and gelatinized at 1 kg/cm² initial pressure presented better crumb mechanical and cellular structural properties compared to the other two pressurized samples and the control.     

木聚糖酶固态罐发酵及尾气在线测定

建立了可对 4个各自独立的 2L玻璃发酵罐同时通气培养和尾气检测的固态发酵系统(SSF) ,以 1 0 0g麸皮和 1 0 0g木屑及 1 5 0mLMandels营养盐溶液为培养基进行木霉T6培养 ,在实验条件范围内找出了最佳产木聚糖酶的环境条件 ,即温度为 3 0℃ ,pH6.0 ,接种量 2 5mL/罐 ( 2× 1 0 8～ 4×1 0 8个孢子 /mL) ,通过对木聚糖酶活力和尾气中CO2 变化的连续测定显示 ,菌体CO2 的释放与木聚糖酶合成具有一定的相关性 ,木聚糖酶的合成与尾气中CO2 含量之间存在着滞后关系 ,尾气CO2浓度在发酵 2 6h达到最高值 ,木聚糖酶活力在 3 9h才达峰值。通过对SSF尾气中CO2 的在线测定 ,能够初步了解SSF中菌丝体生长和产物合成之间的动力学关系     

基于压力平衡的高精度检漏仪的研究

密封器件气密性检测是一项重要的安全检测之一。该检测仪采用微差压原理,利用高精度差压传感器、精密对称气路和嵌入式系统组成测试装置,实现了对一定容积和压力下密封器件气密性的高精度检测。介绍了该检测仪的工作原理、硬件软件结构和系统性能。     

Kinetics of heavy metal vaporization from model wastes in a fluidized bed

Metal vaporization experiments were carried out in an atmospheric fluidized bed to study the influence of operating conditions on the extent of heavy metal (HM) release in fumes from municipal solid waste incinerators. Modelwastes spiked with compounds of Pb, Cd, and Zn were used. The parameters studied were temperature, treatment duration, matrix of the model waste (mineral and organic), HM initial speciation, and gas composition (N2, air, air + HCl, gas mixture simulating the incinerators). The extent of vaporization was measured by solid sample analysis and on-line analysis of the gaseous effluent, after customization of the ICP technique for gas analysis. The results indicate the metal vaporization rate is very high initially and then slows. The results with mineral matrices give the decreasing order of volatility Cd > Pb > Zn, but in industrial incinerators Zn volatilizes slightly more than Pb. Temperature (especially for porous alumina) and mineral matrix have a strong influence on the HM vaporization, but HCl concentration and HM initial speciation do not. The gas composition and the initial metal concentration are significant parameters. The matrix influence clearly denoted the mass transfer limitations in the vaporization process from mineral matrix.     

木霉T6固态罐发酵产淀粉酶与尾气分析

建立了一个 2L玻璃发酵罐的固态通风培养和尾气检测系统。以天然原料麸皮 2 0 0g为培养基 ,加入 15 0mLMandels营养盐 ,接种量 2 5mL( 2× 10 8孢子 /mL) ,自然pH ,室温下 ,对木霉T6进行培养。通过定时取样测定淀粉酶活力 ,并对尾气CO2 连续测定 ,结果显示 ,菌体CO2 的释放与淀粉酶合成具有相关性 ,且呈同步关系。说明尾气的CO2 含量变化可以作为固态发酵某些产物合成的研究参数。     

Low Temperature Drying of Agar Gel Sphere in Desiccated Cold Air Flow

Agar gel spheres (diameter = 4.0, 7.2 and 12.5 cm) were dried in desiccated air flow at low temperatures near freezing point (from ? 9.3 to 10.7°C) at atmospheric pressure. Air velocities ranged from 0.05 to 0.32 m/sec. The drying rates during the constant drying rate period were directly proportional to the moisture vapor pressure at the sample surface. A linear relationship between the drying rate and the square root of the air velocity was obtained at each air temperature. Further, the film coefficients of heat transfer were evaluated and arranged as a semi-empirical dimensionless equation.     

Recent progress in food processing applications of air impingement technology: A review

Air impingement method has been widely used in a variety of industrial applications, such as textile and paper drying, turbine cooling, and glass quenching, because it is an efficient technology with high heat and mass transfer rates. This technology has received increasing interest in the field of food processing over the last two decades, such as drying, baking, blanching, freezing, and thawing. In a food processing equipment using air impingement, jets of high-velocity air (with speeds of 10–50 m/s) are directed at a food product. The performance of the system is influenced by several critical elements, including jet velocity, nozzle array diameter and layout, jet distance, and boundary layer characteristics. The use of computational fluid dynamics, an emerging tool, has been shown to be valuable in the analysis of fluid flow and heat and mass transfer in jet impingement systems. The physical properties of impinging jets, such as turbulent mixing in the free jet zone, stagnation, boundary layer formation, recirculation, and their interactions with food products in terms of heat and mass transfer, have been discussed in this article. The benefits and disadvantages of air jet impingement technology in different food processing applications together with potential trends for improving impingement technology performance were identified and discussed. This review not only contributes to a better understanding of the research status of impingement technology on food processing but also triggers new research opportunities in this field in order to provide more healthy and nutritious food in a more sustainable way to the world's growing population.     

Changes in landfill gas quality as a result of controlled air injection

Air addition has been proposed as a technique for rapid stabilization of municipal solid waste (MSW) in landfills. The objective of this study was to observe the change in concentration of trace constituents of landfill gas in response to air addition. Air injection tests were conducted at a MSW landfill in Florida, and the concentrations of several gaseous constituents at adjacent wells within the waste were measured. The concentrations of methane, carbon dioxide, and oxygen, as well as several trace constituents, were measured both prior to and during air addition. The trace components investigated included a suite of volatile organic compounds (VOCs), nitrous oxide (N20), carbon monoxide (CO), and hydrogen sulfide (H2S). A significant increase in CO was observed in 9 of 14 monitoring points; overall, CO concentrations were found to increase as the ratio of CH4 to CO2 decreased. A significant decrease in H2S was observed at 6 of 14 monitoring points. Air injection did not have a noticeable affect on VOC or N2O concentrations compared to initial levels.