【作者】 王佳莉；

【导师】 王永华； 徐仲伟；

【作者基本信息】 华南理工大学 ， 食品工程， 2011， 硕士

【摘要】 我国每年加工生产大量的金枪鱼制品,随之产生了大量的副产物,这些副产物包括鱼头、鱼骨、鱼皮和鱼内脏等。目前这些副产物尚未得到良好的开发和利用,既污染环境又浪费资源。本论文选取金枪鱼副产物作为研究对象,采用酶水解法水解金枪鱼废弃物,以期为金枪鱼废弃物的综合利用提供理论依据,提高其经济价值。主要研究内容如下:1.对金枪鱼副产物中的基本成分进行分析,结果为:水分含量41.3%,粗蛋白含量42%,脂肪含量2.13%,灰分10.02%。分别采用木瓜蛋白酶、碱性蛋白酶、复合蛋白酶和风味蛋白酶对金枪鱼副产物进行水解,通过单因素试验得出4种酶水解的水解度依次为21.6%、26.89%、22.39%、29.32%,表明风味蛋白酶和碱性蛋白酶的水解效果优于木瓜蛋白酶和复合蛋白酶。2.选取水解时间、温度、初始pH、液固比、加酶量五个因素,分别对碱性蛋白酶和风味蛋白酶的酶解效果进行五因素、四水平的正交试验分析,结果为碱性蛋白酶的最佳工艺条件是:时间42h、温度60℃、初始pH 8.0、液固比6:1、加酶量1%,在此条件下得到的水解液的水解度为29.68%。风味蛋白酶的最佳酶解工艺条件是:时间30h、温度50℃、初始pH7.0、液固比12:1、加酶量1%,在此条件下测得的水解度为31.79%。3.基于风味蛋白酶和碱性蛋白酶作用方式不同,利用双酶复配水解技术进行酶解实验。采用二次旋转正交组合设计试验方案,建立了水解时间、酶比例和初始pH与水解度之间的动态数学模型,并用响应面法对工艺参数进行优化,得到双酶组合的最佳水解工艺条件为:酶解时间37.22h、酶比例2.68、初始pH 7.87,在此条件下测得金枪鱼副产物的理论水解度为41.81%,对优化条件进行实际论证,得到的实际值为40.97%,比理论值稍小,说明响应面法建立的数学模型可为酶解过程中水解度的变化趋势做出很好的预测。用氨基酸自动分析仪对水解液进行检测,得到呈味氨基酸的含量为:天门冬氨酸4.82mg/100ml、甘氨酸7.60mg/100ml、谷氨酸11.12 mg/100ml、精氨酸18.51 mg/100ml和丙氨酸4.51mg/100ml。更多还原

【Abstract】 Many kinds of Tuna food was produced every year. However, during processing procedure, a lot of by-products are generated. At present, these by-products have not been developed and used, which bring both environmental pollution and resources wasting. This paper takes tuna by-products as the object of study in order to provide some basic information for further comprehension utilization of tuna and enhance its economic value. The main contents were as follows:1. Through analysis of Tuna by-products it was found that the content of water was about 41.3%, crude protein 42%, fat 2.13% and ash 10.02%.Papain, Alcalase, Protamex and Flavourzyme were chosen to hydrolyze tuna by-products. Results showed that the degree of hydrolysis of tuna hydrolysate were higher by Alcalase and Flavourzyme than that of Papain and Protamex through single-factor tests.2. Hydrolysis time, temperature, initial pH, liquid-solid ratio, and enzyme quantity were selected as the five orthogonal factors. The orthogonal test results by using Alcalase to hydrolyze tuna by-products were as follows: time 42h, temperature 60℃, initial pH8.0, liquid-solid ratio 6:1 and enzyme quantity of 1%. The DH reached to be 29.68% under these conditions. Otherwise, the orthogonal test results by using Flavourzyme were as follows: time 30h, temperature 50℃, initial pH7.0, liquid-solid ratio 12:1, enzyme quantity of 1%. The DH was 31.79% under these conditions.3. Based on the different hydrolyzing manner between Alcalase and Flavourzyme, dual-enzyme hydrolyzing technology was used for hydrolyzing of tuna in order to get a higher DH. A dual quadratic rotary combinative design scheme was used for analysis. A dynamic mathematic model was designed which showed the connection between hydrolysis degree (Y) and hydrolysis time (A), enzyme ratio(B) as well as initial pH(C).Meanwhile response surface methodology was used to further optimize the process parameters to get the optimum conditions. The optimized conditions were as follows: time 37.22h, enzyme ratio 2.68, initial pH7.87. Under these conditions, the theoreticy DH was 41.81%. The actual value of 40.97% was received from three times of experimental repeatment under these optimal conditions, which showed highly similar to the theoretical value, and means that the response surface method could make a good forecast to the degree trend. Through dual-enzyme hydrolysis of tuna by-products, it was found that the hydrolysate was rich in taste amino acids, including aspartate 4.82mg/100ml, glutamic 7.6mg/100ml, glycocoll 11.12 mg/100ml,aminopropionic 18.51 mg/100ml and arginine 4.51mg/100ml.更多还原