草魚蛋白質在冷藏過程中的變化
蛋白質是魚類肌肉組織的主要組成成分之一,其降解、聚ju合he和he變bian性xing都dou會hui導dao致zhi蛋dan白bai質zhi功gong能neng的de喪sang失shi,從cong而er直zhi接jie決jue定ding魚yu類lei肌ji肉rou質zhi量liang的de好hao壞huai。因yin此ci,在zai草cao魚yu肉rou的de冷leng藏zang過guo程cheng中zhong,蛋dan白bai質zhi的de降jiang解jie和he生sheng化hua變bian化hua往wang往wang是shi魚yu肉rou鮮xian度du下xia降jiang、軟化並最終發生腐敗的重要原因之一
目前,國內外對肌肉蛋白質研究較多的淡水魚主要是鱸魚和鰱魚,且大都集中於蛋白質的提取工藝、lengdongbianxingdengfangmian,duiqizaizhuzangguochengzhongdebianhuayanjiujiaoshao。xianjieduan,yanjiuzhemenduorezhongyuduicaoyubaoxianjishufangmiandeyanjiu,wangwanghushileyouguancaoyuzhuzangguochengzhongdeyixieshencengcishenglishenghuabianhua,tebieshiduiqijiroudanbaizhizaizhuzangguochengzhongdebianhuaguilvyanjiubuduohuolejieshenshao,yinerjinguanduozhongbaoxianxinjishucengchubuqiong,danrengwufayouxiaozuzhicaoyuroudexianduxiajianghefubai。benshiyanyixinxiancaoyuweiyuanliao,yanjiucaoyujiroudanbaizhizailengzangguochengzhongdezuchengtexingbianhua,congdanbaizhibianhuajiaoduchanshucaoyurouzaizhuzangguochengzhongxiandubianhuajili,zhizaiweizhenduixingkaizhanxinxiancaoyudebaoxianjikaifaxiangyingchanpintigongyidingdelilunyiju。
冷藏前4d,水(shui)溶(rong)性(xing)和(he)酸(suan)溶(rong)性(xing)蛋(dan)白(bai)含(han)量(liang)基(ji)本(ben)未(wei)變(bian),鹽(yan)溶(rong)性(xing)蛋(dan)白(bai)含(han)量(liang)稍(shao)有(you)減(jian)少(shao),堿(jian)溶(rong)性(xing)蛋(dan)白(bai)含(han)量(liang)略(lve)有(you)增(zeng)加(jia),可(ke)能(neng)是(shi)因(yin)為(wei)冷(leng)藏(zang)前(qian)期(qi)微(wei)生(sheng)物(wu)作(zuo)用(yong)受(shou)到(dao)抑(yi)製(zhi),肌(ji)肉(rou)組(zu)織(zhi)內(nei)源(yuan)酶(mei)的(de)作(zuo)用(yong)對(dui)蛋(dan)白(bai)質(zhi)的(de)降(jiang)解(jie)有(you)限(xian)。隨(sui)著(zhe)冷(leng)藏(zang)時(shi)間(jian)的(de)繼(ji)續(xu)延(yan)長(chang),水(shui)溶(rong)性(xing)蛋(dan)白(bai)含(han)量(liang)顯(xian)著(zhu)增(zeng)加(jia),鹽(yan)溶(rong)性(xing)蛋(dan)白(bai)含(han)量(liang)也(ye)明(ming)顯(xian)上(shang)升(sheng),但(dan)酸(suan)溶(rong)性(xing)和(he)堿(jian)溶(rong)性(xing)蛋(dan)白(bai)含(han)量(liang)在(zai)逐(zhu)漸(jian)降(jiang)低(di),這(zhe)可(ke)能(neng)是(shi)因(yin)為(wei)冷(leng)藏(zang)4d後hou,一yi方fang麵mian內nei源yuan組zu織zhi酶mei持chi續xu作zuo用yong於yu肌ji肉rou蛋dan白bai質zhi的de效xiao果guo得de以yi積ji累lei,另ling一yi方fang麵mian微wei生sheng物wu繁fan殖zhi和he活huo動dong引yin入ru大da量liang外wai源yuan性xing蛋dan白bai酶mei,從cong而er導dao致zhi大da分fen子zi蛋dan白bai質zhi組zu分fen持chi續xu降jiang解jie,從cong而er改gai變bian了le其qi溶rong解jie性xing。此ci外wai,冷leng藏zang第di8天後,鹽溶性蛋白含量明顯減少,可能是因為此時酸、堿溶性蛋白組分已基本徹底降解,不再或很少轉變為鹽溶性部分,但鹽溶性蛋白還在繼續變化為水溶性蛋白。
淡水魚在冷藏過程中鮮度下降、軟化並最終發生腐敗主要是因為酶催化導致的肌肉內部組分的生理生化變化,而蛋白質為肌肉組織的主要組成部分,其降解、聚合和變性都會導致蛋白質功能的喪失,從而直接決定魚肌肉質量的好壞。本實驗對冷藏過程中草魚肌肉中總蛋白質、不同溶解性蛋白組分和不同結構蛋白組分的變化情況進行了分析,結果表明:冷藏過程中草魚肌肉蛋白質在逐漸發生降解,至第6~8天後肌球蛋白重鏈等大分子質量蛋白質降解加速,幾乎完全消失。
蛋dan白bai質zhi降jiang解jie是shi魚yu肉rou腐fu敗bai的de重zhong要yao表biao現xian,分fen析xi淡dan水shui魚yu肌ji肉rou蛋dan白bai質zhi的de變bian化hua是shi深shen入ru研yan究jiu其qi腐fu敗bai機ji理li的de重zhong要yao手shou段duan,對dui針zhen對dui性xing提ti出chu淡dan水shui魚yu肉rou保bao鮮xian研yan究jiu具ju有you重zhong要yao指zhi導dao意yi義yi。目mu前qian,國guo內nei外wai對dui與yu腐fu敗bai有you關guan的de具ju體ti蛋dan白bai質zhi的de降jiang解jie細xi節jie和he變bian化hua規gui律lv研yan究jiu不bu多duo,了le解jie甚shen少shao。本ben實shi驗yan探tan討tao了le草cao魚yu冷leng藏zang過guo程cheng中zhong肌ji肉rou蛋dan白bai質zhi的de組zu成cheng特te性xing變bian化hua,為wei研yan究jiu淡dan水shui魚yu低di溫wen貯zhu藏zang過guo程cheng中zhong的de肌ji肉rou蛋dan白bai質zhi降jiang解jie規gui律lv提ti供gong了le部bu分fen生sheng物wu學xue證zheng據ju。然ran而er,需xu要yao指zhi出chu的de是shi,本ben實shi驗yan是shi以yi草cao魚yu背bei部bu肌ji肉rou小xiao塊kuai為wei研yan究jiu對dui象xiang,因yin此ci,其qi冷leng藏zang過guo程cheng中zhong蛋dan白bai質zhi的de降jiang解jie情qing況kuang可ke能neng與yu完wan整zheng草cao魚yu的de降jiang解jie情qing況kuang存cun在zai差cha異yi。中國糧油儀器網 http://www.98fo.cn/



