干酪乳杆菌NH-2固态发酵基质的选择及优化

[目的]对干酪乳杆菌NH-2固态发酵基质进行筛选及优化。[方法]以麸皮、米糠及豆粕为候选基质,通过基质发酵保湿性、产物活菌数与表面结构的比较,以及后续的复合基质试验,确定干酪乳杆菌NH-2最佳的固态发酵基质。[结果]麸皮与米糠以3：5的比例混合时为干酪乳杆菌NH-2最佳的固态发酵基质,在该条件下产物活菌数最高可达（85.70±2.35）×108cfu/g。[结论]干酪乳杆菌NH-2能以麸皮、米糠为基质通过固态发酵实现其高密度发酵培养。     

共发酵工艺对酸乳贮藏品质的影响及作用机理

通过测定酸乳发酵及贮藏过程中的pH值、可滴定酸度、持水力及质构特性等指标的变化,采用色差色度仪、顶空固相微萃取-气相色谱-质谱联用和扫描电镜分别对共发酵型酸乳的颜色、风味成分和微观结构进行分析,分析和探讨共发酵工艺对酸乳贮藏过程中品质的影响及相关机理。结果表明：共发酵工艺能显著降低酸乳的pH值,促进酸乳产酸和凝胶,增强酸乳的持水力和质构特性;共发酵工艺的应用能赋予酸乳更好的颜色、风味以及更加致密、连续和稳定的三维立体网状结构。因此,共发酵工艺在酸乳的生产与贮藏过程中能显著改善其品质,提高酸乳的质量。     

餐饮废渣固态发酵生产蛋白饲料过程中菌种和辅料筛选研究

[目的]研究利用餐饮废渣固态发酵生产蛋白饲料过程中的菌种和辅料筛选。[方法]分析餐饮废渣的主要成分,选取8株菌种和6种辅料进行固态发酵试验,以确定最优的菌种和辅料。[结果]白地霉可有效提高产品的蛋白含量,解脂亚罗酵母可分解废渣中的油脂,黄孢原毛平革菌可降解废渣中的纤维素和木质素。复合菌种的接种量为15．0％,白地霉、解脂亚罗酵母、黄孢原毛平革菌3种菌种的最佳配比为3：3：2,餐饮废料与辅料的添加量最佳比例为餐饮废渣：豆饼：麦麸=8：2：1,此条件下,复合菌种以及辅料通过固态发酵生产的高蛋白饲料能够达到饲料的生产要求。[结论]得到餐饮废渣发酵高蛋白饲料的最适菌种和辅料及其配比,为生产出达到国家标准的饲料奠定基础,并为餐饮废渣的处理提供了一条出路。     

以玉米为基质的灵芝固体发酵条件优化

研究了以玉米为基质的灵芝固体发酵,通过单因素和正交试验对工艺条件进行了优化,在测定菌质多糖含量的同时,测定了菌质中还原糖、蛋白质、游离氨基酸的含量。结果表明：玉米粒度、菌种、接种量、发酵温度和时间对基料中菌质多糖的产生及主要成分含量有显著影响,发酵条件优化结果为10目大小的玉米基料,接入12%液体菌种,28℃发酵20d。经优化后,多糖含量可以达到21.97mg/g,还原糖、蛋白质、游离氨基酸含量也优于其它处理组     

Study on structure and molecular dynamics of starch/poly(sodium acrylate)-grafted superabsorbent by <Superscript>13</Superscript>C solid state NMR

The domain-structure of samples containing a series of starch/poly(sodium acrylate)-grafted superabsorbents, pure starch, pure poly(sodium acrylate), and blend of starch/poly(sodium acrylate) has been studied by high-resolution solid-state ¹³C NMR spectroscopy at room temperature. The result shows that the crystallinity of starch decreases greatly in the grafted and blended samples. The values of ¹H spin-lattice relaxation time in rotating frame T _1ρ and ¹H spin-lattice relaxation time T ₁ shows that starch and poly(sodium acrylate) components in both grafted and blended samples have good compatibility in nanometer scale. In the ¹³C cross-polarization/magic-angle-spinning (CP/MAS) spectra, the chemical shift of the carbonyl group of poly(sodium acrylate) depends on the composition of the grafting samples, which indicates that the starch and the poly(sodium acrylate) components of the grafting samples exhibit better compatibility with each other than that of blended samples at molecular level.     

白酒丢糟纤维素降解菌的筛选

[目的]筛选分解白酒丢糟纤维素能力强的菌株。[方法]首先通过采样、培养,测算水解圈与菌落直径比值和滤纸减重率进行初筛,再通过酶活测定复筛得到酶解纤维素能力强的菌株,然后进行固态产酶发酵测定其对丢糟的实际降解和产酶能力。[结果]初筛出23株产纤维素酶菌株,复筛出酶活最强的5株真菌;5株真菌对酒糟的降解能力均较强。[结论]从白酒丢糟筛选出的5株真菌可作为降解丢糟纤维素的优良菌株;该研究为白酒丢糟的综合利用提供了依据。     

Total phenolic contents and antioxidant properties of buckwheat fermented by three strains of Agaricus

The aim of this work was to evaluate the effects of solid-state fermentation (SSF) with three strains of Agaricus (Agaricus blazei Murrill SH26, Agaricus bisporus AS2796 and Agaricus bisporus G1) on the total phenolic contents and antioxidant properties of buckwheat (Fagopyrum esculentum Möench). The results showed that the total phenolic contents of the fermented buckwheat varied with fermentation time and the starter organisms. The total phenolic content of buckwheat fermented with strain SH26 reached its maximum value of 18.07 mg/g after the fermentation of 21 days, which was 3.96 times higher than that of control. The ethanolic extracts of buckwheat fermented by strains SH26 and AS2796 exhibited enhanced antioxidant properties in comparison with the control. However, the ethanolic extracts of buckwheat fermented by strain G1 exhibited less antioxidant properties in comparison with the control. The ethanolic extracts of buckwheat fermented with strain SH26 exhibited the highest reducing power, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity and ferrous ion chelating ability, respectively. The ethanolic extracts of buckwheat fermented with strain AS2796 exhibited the highest superoxide anion radical scavenging ability.     

固态发酵产游离氨基酸的条件优化研究

[目的]为提高曲霉菌种固态发酵产游离氨基酸水平。[方法]以11种豆类为固态发酵培养基,研究其对米曲霉、黑曲霉、毛霉产游离氨基酸的影响,同时设计正交试验优化米曲霉产氨基酸的培养条件。[结果]在以黄豆为培养基时,米曲霉产氨基酸最多,达64.65mg/g,其次是毛霉。11种豆类培养基在接种米曲霉后,其氨基酸的含量明显提高,尤其是黄豆、蚕豆、绿豆,相对提高率依次为824.9%、785.9%、761.3%。正交试验表明,培养时间对游离氨基酸产量的影响最大,其次是装料量,再次是接种量。[结论]最佳的生产工艺是接种量10%,装料量40 g,培养时间8 d。     

红曲霉固态发酵控制条件对色素及桔霉素生产的影响

[目的]探讨红曲霉固态发酵控制条件对色素及桔霉素生产的影响。[方法]通过改变红曲霉(FF-6202)固态发酵的条件,研究发酵过程中烘干温度,发酵时间,接种量,发酵温度及翻曲次数对色素和桔霉素的影响。[结果]50℃时桔霉素的含量最大。随着温度升高,色素和桔霉素损失增大。桔霉素的生成量随着固态发酵时间的延长而增大,到96h时达到最大。所产色素随着接种量的增加而增多,12%接种量时为最多。变温培养时红曲霉产桔霉素量增加,恒温培养时色价高于变温培养时。降低固态发酵翻曲次数,可同时降低桔霉素和色素的产量。[结论]红曲霉固态发酵最佳控制条件为:烘干温度50℃,发酵时间在96h内,接种量12%,温度恒温34℃,发酵后期的翻曲次数减少为1次。     

红曲霉固态发酵产红曲色素研究进展

红曲色素是天然色素,具有营养、无毒、多功能等优点。固态发酵是红曲色素生产的传统方法,与液体发酵相比具有独特的优点,一直受到研究者关注。对国内外近期关于红曲色素研究的报道进行了综述,对影响固态发酵产红曲色素的条件进行了归纳和分析,可为红曲色素固态发酵的推广提供借鉴。