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酯化红曲的筛选和酯化酶酶学性质研究 总被引:1,自引:0,他引:1
从洋河大曲中筛选到l株具有较高酯化活力的红曲霉,经26S RNA分子鉴定为紫红曲霉(Monascus purpureus),命名为YHM-6.YHM-6菌株能分别耐受8‰的乳酸和10 %vol的酒精.以YHM-6为出发菌株,生产得到酯化红曲粗酶制剂催化己酸合成己酸乙酯具有很强的专一性和选择性.结果表明,其最适催化温度为35℃,最适催化pH值为3.5,最适催化酒精浓度为28 %vol,最适己酸浓度为1%,其适合于浓香型白酒和黄水酯化液的生产. 相似文献
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酯化红曲在白酒生产中的重要作用 总被引:6,自引:1,他引:6
酯化红曲是由红曲菌种和多种产酯功能菌混合培养而成,酯化活力高。在白酒正常生产中加入原料的2%。用曲20%时,可以降低酒酷酸度0.1~0.2度,出酒率稳定在40%以上,优质酒率在50%以上;在夏季压害和秋季转排期间加入酯化红曲,可有效地防止掉排;在制曲原料中加入0.5%~1%的酯化红曲培养成强化大曲,可提高酯化力3.8mg/g曲。提高16.8%;在生产酯化液的应用中加入8%酯化红曲,可使己酸乙酯达到25g/L以上。 相似文献
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从大曲中分离出一株酯化菌WD-5,经初步鉴定为红曲霉菌,其酯化为达685mg/100ml,将该菌应用于黄浆水酯化技术中,通过实验找到了最佳黄浆水酯化条件,为厂创造了良好的经济效益。 相似文献
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红曲霉培养条件对酯化力影响的研究 总被引:3,自引:0,他引:3
以A13、As3.554和As3.972为研究对象,比较了其培养参数米坯的初始水分、培养时间及以葡萄糖和蔗糖为速效碳源及添加量对底物己酸和乙醇转化为脂肪酸酯的酯化力的影响规律.实验结果表明.蒸米坯的初始水分、培养时间对其酯化力均有显著的影响,其最适水分为50%,培养时间为24d,葡萄糖可作为其培养初期的速效碳源,添加量视其菌株性能而存在一定差异.HS-SPME耦联GC-MS剖析不同红曲菌株制成的曲粉所催化得到的产物组分表明,其主要产物与总酯化力之间存在相关性,其酯化物的种类取决于菌株的特性. 相似文献
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该研究从赤霞珠酿酒葡萄表皮分离高产类胡萝卜素的酵母菌株,并研究了温度、氧化剂、还原剂及酸度调节剂等因素对菌株所产类胡萝卜素稳定性的影响。结果表明,从酿酒葡萄表皮分离到6株产类胡萝卜素较强的酵母菌,其中酵母菌Y7在以葡萄糖为碳源、蛋白胨为氮源的液体培养基中类胡萝卜素产量较高。经形态观察、生理生化特性和ITS基因序列分析鉴定,菌株Y7属于粘红酵母(Rhodotorula glutinis)。酵母菌生产色素的基本稳定性良好,但高温(>40 ℃)、添加氧化剂(H2O2)、还原剂(亚硫酸钠、抗坏血酸)和酸度调节剂(柠檬酸、柠檬酸钠)使其稳定性下降,但影响较小,加入苹果酸和氢氧化钠对类胡萝卜素有增色的效果。研究结果将为粘红酵母Y7在类胡萝卜素商业化生产中的应用提供参考。 相似文献
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为开发一款含有功能性红曲米粉的口感较好的工程米,以糙米、薯粉等粗粮为主要原料,采用双螺杆挤压的方式制备红曲米粉,其添加量分别为0.5%、1%、2%、4%的4款工程米。利用电子舌、电子鼻和质构仪对工程米的感官指标进行测定。结果表明:随着功能性红曲米粉添加量的增加,工程米的口感品质有明显差异,2%及4%添加量的工程米苦味升高,而0.5%添加量涩味最明显;1%添加量在甜味、鲜味及丰富度指标方面较高,且苦味、涩味较低;1%及4%添加量硬度、弹性等质构特性较好,且1%添加量能够赋予产品更加明显的风味特征,说明功能性红曲米粉添加量为1%的工程米口感最佳。 相似文献
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Rodríguez ME Infante JJ Molina M Rebordinos L Cantoral JM 《International journal of food microbiology》2011,145(1):331-335
The analysis of restriction fragment length polymorphism of mitochondrial DNA (mtDNA-RFLP) has been applied as a test to monitor the abundance of the starter yeast strain during industrial wine fermentations without previous isolation of yeast colonies. For white wine fermentations, we performed a rapid assay consisting in taking a sample of fermenting must, purifying the DNA from harvested cells, and obtaining the restriction patterns by digestion with the endonuclease HinfI. The same protocol, but adding an overnight cultivation step before DNA purification, was also applied to red wine fermentations. The results were compared with those obtained from the subsequent characterisation of strains, for the same samples, by analysis of the electrophoretic karyotype of isolated yeast colonies. In all cases, when the inoculated strain was dominant within the yeast population, the rapid assay anticipated the result by showing the coincidence between the restriction profiles obtained from both total cells and the inoculated strain. The results were obtained at 11 or 23 h after sampling for white- or red-wine fermentations respectively. This method allows a rapid intervention of the wine-producer if the presence of the inoculated yeasts has suffered a sudden decrease in any phase of the fermentation process. 相似文献
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该实验从红提葡萄发酵过程中分离出酵母菌株,并对其耐受性进行研究,旨在提高红提葡萄酒酿造品质。通过培养不同发酵时期菌株,并用肉眼和显微镜分别观察其菌落和细胞形态,再测定其发酵能力、耐糖性、耐酸性、耐酒精度。结果表明,共分离出酵母菌140株,经菌落形状和细胞形态鉴定后,获得典型的三类共6株酵母菌;在发酵过程中,加入分离菌株比自然发酵可多发酵1.6%葡萄糖,多产生0.78% CO2和0.82%vol的酒精,且发酵趋势和安琪酵母、自然发酵过程一致;以安琪酵母为对照,对6株菌进行耐糖性、耐酸性、耐酒精度试验,得出综合耐受性较好的酵母菌株为A3、B7和C1。 相似文献
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酯化红曲在浓香型白酒生产中的应用及实例 总被引:1,自引:0,他引:1
主要介绍酯化红曲在浓香型基酒生产中的应用,通过诸多厂家的生产实验,分析总结实验数据.得出酯化红曲强化基酒生产的最佳工艺条件. 相似文献
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Evaluation of the Ability of Polyphenol Extracts of Cocoa and Red Grape to Promote the Antioxidant Response in Yeast Using a Rapid Multiwell Assay
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Ana Peláez‐Soto María Teresa Fernández‐Espinar Patricia Roig José Vicente Gil 《Journal of food science》2017,82(2):324-332
Saccharomyces cerevisiae has been used as a model organism to study the capacity of cocoa and red grape extracts to trigger an antioxidant response. A methodology adapted to microtiter plates has been developed to monitor yeast growth after culture preincubation with food ingredients and exposure to oxidative stress by hydrogen peroxide and menadione. This methodology proved effective in measuring the ability of cocoa and red grape extracts to promote an antioxidant response in yeast, and also the prospect of conducting dose–response studies. Additionally, the method has proven useful to perform studies with mutant strains lacking genes that may be related to the mechanism of action underlying the antioxidant properties. Thus, in a single assay, it is possible to elucidate the sensitivity of strains to oxidative stress, the ability of an ingredient to promote an antioxidant response, and the possible implication of certain genes. Results of assays using strain hst3Δ showed that the antioxidant protection provided by exposure to cocoa and red grape extracts was not present in the strain lacking gene HST3 when H2O2 and menadione were used as oxidizing agents. This effect was previously reported for cocoa extract only, with H2O2 as stressor. Moreover, the results showed that the mutant strain hst3Δ is more resistant to menadione and H2O2 in the absence of preincubation with cocoa and red grape extract, hinting at the possible implication of sirtuin Hst3 in the antioxidant cellular response. 相似文献