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1.
红曲为常用天然色素,红腐乳灌坛时必用红曲。木文用72—分光光度计和581—G型光电比色计测定红曲的色价及红腐乳汤汁的色价。在样品处理、色价标准方面进行了一系列探讨。  相似文献   

2.
分析青稞红曲色素稳定性的因素,寻找到青稞红曲色素的特征,以便于指导生产和应用。用紫外可见分光光度计在505 nm波长处测定青稞红曲色素溶液吸光度的变化,来判断色价改变情况。青稞红曲色素水溶液日光直射0.5 h即可使色价保存率降低到66.94%;日光灯处理时光照强度越高,色价损失越明显;低于60℃时热稳定性较高,短时间高温环境对色价损失影响不大,超过1h的高温处理会对色价保存率有明显的影响;青稞红曲色素水溶液在pH5至pH9基本上趋于稳定;Cu~(2+)、Fe~(3+)加入后对青稞红曲色素水溶液稳定性影响明显,其他离子无明显影响。加工、贮藏过程中青稞红曲应当避免日光照射、高温、过酸过碱和Cu~(2+)、Fe~(3+)存在的环境。  相似文献   

3.
对6种不同品牌市售红曲米的色价及稳定性进行了探讨。结果表明,不同品牌红曲米的色价存在明显差异,其中5号样品具有最高红曲红色素色价,同时也显示出较高的橙色素和黄色素色价;不同pH值、温度和光照条件对6种红曲米中红曲色素稳定性有重要影响,5号样品的红曲红色素色价的稳定性相对较好,可用作后续红曲黄酒的发酵原料。  相似文献   

4.
通过分析70%乙醇提取红曲色素过程中的色价-时间的变化关系,结合经典传质数学模型,建立了提取过程中红曲色素色价与提取时间的动力学方程.经验证,所推导出的动力学方程能较好地反映红曲色素提取过程中色价-时间之间的关系.  相似文献   

5.
目前,红曲主要以大米为原料生产,成本较高,以玉米为原料生产玉米红曲可降低生产成本。为了更好地开发利用玉米红曲,以色价保存率为指标,研究了光照、温度及在空气中振荡对玉米红曲红色素稳定性的影响,为玉米红曲在食品中的应用奠定基础。研究结果表明,自然光和日光照射对玉米红曲红色素的稳定性影响显著,照射时间越长,色价损失越大。高温处理对玉米红曲红色素的影响显著,但高温下短时间加热,色价损失率较小,100℃下加热0.5h,色价的保存率仍为90.1%。低温和在空气中振荡处理对玉米红曲红色素的稳定性影响不显著。  相似文献   

6.
小米红曲是红曲霉接种于小米上发酵而得。通过单因素实验,采用测定小米红曲的色价的方法,研究了初始含水量、中间加水量、底物量、发酵温度、第一次加水时间、发酵时间对固体发酵制备小米红曲的影响。  相似文献   

7.
考察了装液量、时间、接种量、金属离子、维生素等因素对红曲霉液体发酵产红曲色价的影响及pH、光照和添加剂对红曲色素稳定性的影响。结果发现当培养装液量为75mL/250mL,培养时间为7d,接种量为9%,硫酸亚铁添加浓度为0.005mmol/L,维生素B1添加浓度为0.03%时,红曲霉产红曲色素的色价最高,可达714.80U/mL。红曲色素在pH为7的环境下放置8h时,红曲色价达到最大值,为782.1U/mL;最适保存方式是避光保存,在避光下放置72h,红曲色素的色价仍有508U/mL;食品添加剂苯甲酸钠和亚硝酸钠对红曲色素具有一定的增色作用,但是添加一定量的EDTA会使红曲色素的色价降低,维生素C和双氧水对红曲色素的影响不大。  相似文献   

8.
以色价为指标,研究了光照、温度、金属离子、螯合剂及抗氧化剂对红曲色素的稳定性的影响,结果表明:有利于保持红曲样品的色价的光照条件顺序为,避光条件>紫外线>漫射光>日光;在综合因素作用下,常温、0.02%的Mg2+及0.02%的螯合剂EDTA有利于红曲色素色价的保存.  相似文献   

9.
红曲色素高产菌株的诱变筛选及液态发酵初探   总被引:5,自引:0,他引:5  
从不同的红曲样品中分离纯化获得红曲霉菌株 5株 ,以此为菌种液态发酵制备红曲 ,选出发酵后菌丝体色价与发酵原液色价都相对较高的编号为M3的菌株为出发菌株 ,进行了6 0 Co γ射线的诱变 ,获得了编号为M 3 2相对高产的色素菌株 ,其发酵后菌丝体总色价和发酵液总色价分别提高了 2 7 0 8%和 2 5 90 %。并对其液态发酵制备的红曲色素进行了质量分析。  相似文献   

10.
红曲霉在中国的生产及其应用(下)   总被引:7,自引:0,他引:7  
在阐述中国红曲传统制造方法的基础上,介绍了现今酿酒用红曲生产工艺、高色价红曲的生产技术以及功能红曲的生产与探讨,并展望了红曲产业的前景。  相似文献   

11.
木瓜蛋白酶的提取及应用研究进展   总被引:1,自引:0,他引:1  
本文主要介绍木瓜蛋白酶的组成,重点阐述提取方法、提取工艺的研究进展,进一步介绍木瓜蛋白酶在食品工业特别是在食品加工中的应用,并对其在医药、化工及未来食品加工方面的应用前景进行展望。  相似文献   

12.
Antioxidants play a vital role in protecting the skin from environmental distress. As the skin is constantly exposed to harmful UV radiation, endogenous antioxidants present in the superficial layers of the skin neutralize reactive oxygen species. Over time, antioxidants become depleted and loss their protective effect on the skin. Therefore, supplementing skin with topical antioxidant can help replenish this loss and fight the oxidative stress. The objective of this study was to deliver antioxidants topically and quantify the amount permeated in the stratum corneum and underlying skin. Polyphenols (catechin, resveratrol and curcumin) and vitamin (retinol) with various lipophilic properties were delivered via porcine ear skin, using propylene glycol as a vehicle. The amount in the stratum corneum and underlying skin was quantified using tape stripping and skin extraction methods, respectively, and samples were analysed via HPLC. All four antioxidants permeated into the skin from the propylene glycol vehicle. The order of the amount of antioxidant in the stratum corneum was catechin > resveratrol~ retinol> curcumin, whereas that in the underlying skin was retinol > catechin~ resveratrol~ curcumin. Of the total amount of polyphenols in the skin, approximately 90% was retained in the stratum corneum whereas 10% was quantified in the underlying skin. In contrast, 10% of retinol was retained in the stratum corneum whereas 90% permeated in the underlying skin. Polyphenols (catechin, resveratrol and curcumin) showed high concentration in the stratum corneum whereas retinol showed high accumulation in the underlying layers of the skin.  相似文献   

13.
本文介绍了几十年以来水氯镁石脱水研究的进展,给出了该项研究在热力学、动力学以及相平衡领域中的最新成果,并介绍了脱水过程中关键技术难题以及该项目研究目前存在的问题。同时,预测了该研究项目工业应用前景。  相似文献   

14.
预处理对六种黄酒酿造原料酿造特性的研究   总被引:1,自引:0,他引:1  
为探究不同黄酒酿造原料的酿造特性,以红谷、张杂谷、圆糯米、黍米、金米、粳大米等六种谷物为原料进行浸泡和蒸饭实验,监测浸泡过程中不同原料质构和色泽的动态变化;比较了浸泡后六种米浆水的有机酸和氨基酸组成;并对蒸饭中挥发性风味物质的含量进行分析。结果表明,浸泡过程中六种谷物的颜色和质构参数存在显著差异(P<0.05)。红谷米浆水的总氨基酸含量最高(976.49 mg/L),乙酸、酒石酸和柠檬酸含量显著高于其他谷物米浆水的相应含量(P<0.05)。六种谷物蒸饭样品中共检出165种挥发性成分,其中红谷蒸饭中酸类(11.75 μg/100 g)和酚类含量(10.54 μg/100 g)远高于其他谷物。综上所述,红谷米浆水中氨基酸含量以及蒸米中酸类香气成分较高,这有利于发酵醪的进一步微生物发酵。  相似文献   

15.
The precipitation of proteins due to the changes in pH has been a major limiting factor in their utility especially when the precipitation is concurrent with irreversible aggregation. In the present study, an attempt is made to see the effect of glycerol on the pH-induced aggregation of α- globulin which is the major protein fraction (11S) from Sesame (Sesamum indicum L.) seeds. A second order polynomial relation existed between the cosolvent concentration and precipitation which was prevented in presence of the cosolvent. Similarly, there was a second order polynomial relation between 8-anilino 1-naphthalene sulfonic acid (ANS) binding of the protein (as indicated by fluorescence emission at 466 nm) and the cosolvent concentration. The relative precipitation in presence of glycerol is however linearly proportional to the changes in surface hydrophobicity as seen by behavior of ANS with the protein in presence of the cosolvent. A possible role of the cosolvents in prevention of aggregation due to hydrophobicity of the protein is envisaged and the relation between the different parameters is discussed.  相似文献   

16.
目的 分析食用油中酸价测定的不确定度来源并建立不确定度评定方法, 为检验数据的可靠性和准确性提供参考。方法 依据GB 5009.229-2016《食品安全国家标准 食品中酸价的测定》和JJF 1059.1-2012《测量不确定度评定与表示》建立数学模型, 计算各变量的不确定度, 最终计算扩展不确定度。结果 结果显示, 样品中酸价的扩展不确定度为U=1.764×10?3 mg/g, 样品中酸价含量为(0.16±0.002) mg/g(置信水平95%, 包含因子k=2)。结论 在测定过程中, 测量重复性对总的不确定度影响最大, 其次是滴定管的体积。  相似文献   

17.
对浓香型白酒生产工艺方向等问题的思考   总被引:1,自引:0,他引:1  
随着白酒科技的进步,新思维和新观点不断产生,在不同的历史时期,对浓香型白酒的生产工艺方向产生不同程度的影响。其影响有正面的,也有负面的。有的企业为生产工艺方向思索探讨;有的企业跟风效仿;有的企业坚持走自己的路线。必须全面、准确、客观地认识中国白酒的发展方向;努力实现浓香型纯粮白酒不添加外加香的目标;解决基酒中的怪杂味;坚持走以增加己酸乙酯的自然生成量为主的质量之路:正确对待白酒的酿造与勾调工作,才能把握和发展浓香型白酒的生产工艺,全面推进白酒业的进步。(孙悟)  相似文献   

18.
Circulating levels of vitamin A (retinol) and lactoferrin (Lf) are low in calves at birth. Bovine colostrum contains relatively high amounts of vitamin A and Lf, and both substances are intestinally absorbed by neonatal calves. There is evidence that these compounds interact with insulin-like growth factor binding proteins and thus influence the status and effects of insulin-like growth factor. The hypothesis was therefore tested that vitamin A and Lf influence epithelial growth, development, and absorptive capacity of the small and large intestine and modulate intestinal immune tissues (Peyer's patches; PP). Four groups of calves (n = 7 per group) were fed a milk-based formula with or without vitamin A and (or) Lf. Group F received formula (F) only; group F(A) was fed F supplemented with vitamin A; group F(L) was fed F supplemented with Lf, and group F(AL) received F plus vitamin A plus Lf. An additional group of calves (group C; n = 7) served as positive control and was fed colostrum (C) from pooled milk obtained on d 1, 2, and 3 of lactation. Amounts of nutritive components in formula and colostrum were similar. Blood samples were taken to measure vitamin A and Lf, and plasma xylose (added on d 4 to feeds) was measured postprandially for 8 h as a marker of intestinal absorptive capacity. Plasma vitamin A was low at birth and further decreased in groups F and F(L), but increased in groups F(A), F(AL), and C. Plasma Lf was low at birth and transiently increased up to 4 h after the first meal in group C. Xylose absorption was higher in group C than in other groups. Incorporation of 5-bromo-2'-deoxyuridine into DNA (as a measure of cell proliferation rate) was enhanced in intestinal crypts in groups F and F(L) at all intestinal sites. Ileum villus heights of groups F and F(L) were smaller than of groups F(A) and F(AL). Villus height to crypt depth ratios were smaller in F-fed groups (especially in groups F and F(L)) than in C-fed calves in the duodenum and jejunum. Incorporation of 5-bromo-2'-deoxyuridine into colon crypt cells of group F was greater than in groups F(L) and F(A). Sizes of follicles of PP in the ileum were greater in group F(A) than in group F. In the ileum, vitamin A and Lf tended to interact with PP size. In conclusion, feed supplementation of vitamin A and Lf influenced growth of the ileum and colon. Interactions were observed between vitamin A and Lf on epithelial cell maturation, villus growth, and size of follicles in PP of neonatal calves.  相似文献   

19.
黄酮类化合物的应用研究进展   总被引:1,自引:0,他引:1  
自然界的多种植物中均有黄酮类化合物的存在,其具备多种生理活性和药用价值,受到研究者的广泛关注。近年来,黄酮类物质被大量应用在新型药品的研制、食品及化妆品工业中,在疾病的预防和治疗、食品保藏、天然化妆品开发等领域发挥了愈加重要的作用,特别是在作为天然食品添加剂的应用中,黄酮类化合物不仅起到了延长食品贮藏期、为食品提供自然温和的色泽、香气等作用,还能使食品摆脱人工合成添加剂的毒性等弊端,提高食品的安全性和保健价值。本文综述了黄酮类化合物的分类及主要食物来源,及其在医药、食品、化妆品工业中的应用,为添加黄酮类物质的新型药品、食品添加剂、保健品、护肤品的开发提供理论支持,为黄酮类化合物的综合利用提供依据。  相似文献   

20.
目的 本研究分析了水煮和烘烤两种加工方式对贝类元素生物可及性的影响。方法 采用体外模拟消化试验,利用电感耦合等离子体质谱仪(ICP-MS)分析了牡蛎和扇贝体内8种元素(Pb、As、Cd、Cu、Fe、Zn、Mn、Hg)的生物可及性和浓度的变化。结果 两种贝类元素含量的趋势大体一致,从高到低依次为锌>铁>铜>镉>砷>铅>汞。两种贝类中生物可及性最高的是牡蛎中的砷元素,为98.4%。生物可及性最低的是扇贝中的铁元素,为3.4%。经过不同的加工方式处理后,能显著提高两种贝类锰元素的生物可及性,但是能显著降低牡蛎中铜、砷、铅元素的生物可及性。加热处理后扇贝中砷和镉元素的生物可及性增加。相较于蒸煮的加热方式,烘烤的加工方式对贝类元素生物可及性的影响更大。结论 贝类元素生物可及性不仅与元素种类、载体、加工方式相关,也与其他元素浓度相关。  相似文献   

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