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热力法和酶解法提取鱼鳞胶原蛋白的工艺及性质研究 总被引:3,自引:1,他引:3
以草鱼鱼鳞为原料,采用热力法和酶解法提取鱼鳞中的胶原蛋白,用正交实验优化提取工艺,分析所得胶原蛋白的性质。酶解法提取草鱼鱼鳞胶原蛋白的最佳工艺条件为:每克蛋白中加入7500U的Alcalase碱性蛋白酶,鱼鳞∶水=1∶20(w/v),60℃水解4h,胶原蛋白的水解度为6.43%。热力法提取的最佳工艺条件为,鱼鳞∶水=1∶20(w/v),121℃提取15min,提取率为45.47%。酶解法提取的胶原蛋白的黏度、吸水性和起泡性大于热力法提取的,但保水性、乳化能力和乳化稳定性及泡沫稳定性小于热力法提取的。 相似文献
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《中国食品学报》2015,(12)
利用废弃的青鱼鱼鳞制备胶原蛋白肽,不仅能够减少环境污染,还可以明显提高鱼类加工废弃物的综合利用,提高经济效益。采用青鱼鱼鳞为原料,通过测定胶原蛋白溶出率及脱钙率,优化温水清洗及盐酸脱钙的预处理条件;测定酶解液水解度及低聚肽占成品百分含量,确定并优化复合酶水解的条件,得到所需的肽。最佳工艺条件:(1)采用料液比为1∶15的50℃温水水洗2 h,可得表面无杂质、胶原蛋白溶出率仅为2.2%的鱼鳞;(2)在0.4 mol/L盐酸与料液比为1∶10条件脱钙30 min,脱钙率达94%,而其工艺过程中的胶原蛋白溶出率仅有0.15%;(3)采用2 000 U/g的木瓜+菠萝+碱性蛋白酶(1∶1∶2),50℃自然p H下酶解5 h,获得水解度47%的胶原蛋白低聚肽,其分子质量主要分布在180~1 000 u和1 000~2 000 u两段,含量分别为73.3%和16.6%。成品胶原蛋白低聚肽颜色为白色泛微黄,具有很好的溶解性。 相似文献
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《食品工业科技》2017,(5)
本研究以仿刺参精(Apostichopus japonicus spermary,ASJS)为材料,以水解度为指标优化了酶解工艺条件,并考察了酶解产物的体外抗氧化效果。实验选用木瓜蛋白酶(PAP)、复合蛋白酶(PRO)和风味蛋白酶(FLA)作为实验用酶,以双缩脲法结合三氯乙酸法测定水解度,通过单因素与正交实验,优化了单酶酶解工艺条件,并与双酶及三酶复配水解进行了比较实验,最后对不同的水解产物进行了体外抗氧化活性测定。结果表明:单酶最佳酶解工艺条件为PAP:酶添加量3.0%、温度70℃及反应时间4 h;PRO:酶添加量3.0%、温度45℃及反应时间4 h;FLA为:酶添加量2.0%、温度45℃及反应时间4 h。在最佳酶解工艺条件下PAP水解度为32.14%,PRO为31.09%,FLA为11.89%。双酶及三酶的复配水解工艺检测到的水解度均低于单PAP及单PRO。不同水解产物清除羟自由基和超氧阴离子自由基能力结果为,在样品浓度为5 mg/m L和10 mg/m L时,ASJS的PAP酶解产物好于PRO、FLA、双酶、三酶复配,同时也好于仿刺参卵及体壁PAP酶解产物。综上可知,ASJS的PAP水解产物显示出较好的体外抗氧化活性,可以进一步开发利用。 相似文献
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双缩脲法测定罗非鱼源胶原蛋白肽含量的改良及应用评价 总被引:1,自引:0,他引:1
为探究罗非鱼源胶原蛋白肽含量的快速测定方法,以罗非鱼皮胶原蛋白肽为对照品,改良双缩脲比色法测定肽含量的操作方法,考察显色络合物最大吸收波长、线性拟合度高的肽和三氯乙酸(trichloroacetic acid,TCA)用量范围、pH值;在优化条件下对标准曲线进行重复性、精密度评价以及加样回收率实验;研究本方法对不同分子质量罗非鱼皮及鱼鳞胶原蛋白肽体系检测的适用性。结果显示,当胶原蛋白肽(标称分子质量3 kDa)质量浓度在0.3~1.5 mg/mL范围内,使用13% TCA溶液,调整体系pH 12.5,在波长545 nm处检测,吸光度与肽质量浓度线性拟合好(R2=0.999),标准曲线方程为y=0.144 9x+0.001 5;重复性和精密度实验得到相对标准偏差(relative standard deviation,RSD)分别为1.86%和1.84%,加样回收率分别为113.9%、109.7%,RSD分别为1.39%、1.00%;线性范围宽、重复性好、准确度高。将本法应用于不同种类罗非鱼肽产品体系的检测,加样回收率相差不大,偏差均较小,说明本法简便、快捷,适用于罗非鱼源肽含量的检测。 相似文献
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A review is given of the different composition of biuret test solutions and experiments with the estimation of protein content of milk, cheese and meat by means of the biuret method are reported. The pure protein and the casein content of skimmed milk and the protein content of whole milk could be determined with biuret test solutions containing potassium hydroxide and a detergent. The use of the biuret method is advantageous in the case of cheese and meat, which are dissolved in potash lye or alkaline detergent solutions. Disturbances of the biuret method caused by lactose, fat or turbidity were eliminated after addition of hydrogen peroxide, by means of extraction or of additional measurements with a copper-free, zinc-containing biuret reagent. Deviations of the color intensity of biuret complexes were compensated by inclusion of standards in the measurement series. 相似文献
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稻米蛋白质测定方法的比较与分析 总被引:6,自引:0,他引:6
分别利用凯氏定氮法和双缩脲法对10个稻米样品的蛋白质含量进行测定。比较发现,两种方法的测定结果并不相同,并表现出双缩脲法的测定结果较凯氏定氮法小约10%~20%的规律。提出利用已标定蛋白质含量的稻米为标样,基于双缩脲反应原理,进行蛋白质测定的分析方法,结果表明,该法可获得较高的检测精度。 相似文献
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几种测定油料饼粕粗蛋白含量方法的探讨 总被引:3,自引:0,他引:3
采用国家标准规定的凯氏定氮法、改进后的凯氏定氮法以及双缩脲法同时测定油料饼粕中粗蛋白含量,并对三种方法进行比较。结果表明:改进后的凯氏定氮法同国际法相比结果偏高,更皎皎于饼粕中实际粗蛋白含量;采用双缩脲法有测定结果相对平均偏差较大,但操作简便,效率高,更适合于生产厂家进行快速测定大量样品时使用。 相似文献
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The effects of electrical stimulation (ES) on both hot-processed, brine-chilled (BC) and conventionally processed (CON) pork loins were evaluated. Protein solubility changes from water extracts of treated pork longissimus were monitored by size exclusion high-performance liquid chromatography (SEC/HPLC) and the biuret protein reaction. Molecular weight profiles (SEC/HPLC) of water extracts from treated longissimus showed four major peaks that represent proteins with molecular weights greater than 10,000 daltons which were affected by ES. Electrical stimulation led to a decrease in the amount of proteins observed in these four peaks when the conventional method of chilling was employed. At the same time, an increase in smaller molecular weight compounds were observed (compounds < 10,000 daltons). Extractable biuret positive compounds showed no significant changes due to ES or method of chilling. 相似文献
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Vikrant Narwal Neelima Sharma Rajan Sharma Yudhishthir S Rajput Bimlesh Mann 《International Journal of Dairy Technology》2018,71(2):539-543
Glycomacropeptide (GMP) is a nutraceutical additive, which is released during cheese preparation. In this study, the protein content in a laboratory GMP preparation and two commercial GMP samples, which was estimated by the Bradford, biuret, Lowry and bicinchoninic acid (BCA) assays, were compared using the Kjeldahl method. There were apparent differences in the values of estimated proteins using the different methods. An absence of dose response in the Bradford method and a low dose response using the Lowry method indicated the unsuitability of both these methods. Absorbance in the biuret and BCA methods linearly increased with increasing GMP content. The BCA method was the most sensitive of these methods. 相似文献
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A method is described for the quantitative determination of the protein content in dried yeasts. A special pretreatment to break the yeast cell wall is used followed by a biuret determination. 相似文献
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C. E. O'Hara 《Journal of the science of food and agriculture》1968,19(3):117-118
A highly significant interaction between concentration of free reducing sugar (glucose) and total time of the biuret reaction has been found by following absorbence changes. However, concentrations of up to 12.5 mg glucose/25 ml biuret reagent subjected to a reaction period of 1 1/2 hours caused no interference in absorbence value. Conditions for the specific application of the biuret colorimetric reaction for the determination of wheat flour proteins in the presence of free reducing sugars have been defined. 相似文献