以轉麩醯胺酶改質植物蛋白建立植物蝦加工資料庫

Applying Transglutaminase Modified Plant Proteins to Establish a Database for Processing of Vegetarian Shrimp

近年來植物肉市場蓬勃發展，目前素蝦產品為蒟蒻製造其口感不佳，因此本研究為增加植物蝦口感，選用四種商業化植物蛋白（大豆、豌豆、小麥及藍藻蛋白）為原料，藉由添加不同濃度(0.1及0.5%)轉麩醯胺酶(transglutaminase；TGase)，於不同溫度(25及50℃)及時間（20及60分鐘）下反應，探討生成蛋白質產物特性及質地變化，且與三種不同種類的新鮮冷凍蝦（草蝦、明蝦及波士頓龍蝦）進行比較，並由此建立資料庫以供未來植物蝦製造。實驗結果顯示從游離胺基酸、分子量大小及表面疏水性三方面，龍蝦、草蝦及明蝦的蛋白質特性略微不同，在掃描式電子顯微鏡中觀察內部結構亦存在差異；而在植物蛋白中也發現，當加入TGase後會使蛋白質有顯著的變化，且當TGase濃度、反應溫度及時間提升時對蛋白質特性及質地變化更明顯，但對藍藻及小麥蛋白並無明顯影響。本研究發現，大豆及豌豆蛋白添加TGase後之蛋白質產物特性與新鮮冷凍龍蝦較為接近，因此建議製作植物蝦時可使用大豆或豌豆蛋白，並添加0.5%的TGase做為基礎，可製造出與新鮮冷凍龍蝦相似蛋白質特性及口感的植物蝦，而藍藻及小麥蛋白做為增加鮮味及增加食品彈性與延展性的原料。

In recent years, vegetarian meat has flourished in the market, but vegetarian shrimp is not ideal because it is made from konjac, which does not have the same texture as shrimp. In an effort to improve the texture of vegetarian shrimp, this study used different commercial plant proteins (soy, pea, cyanobacteria and wheat protein) with different transglutaminase (TGase) concentrations (0.1% and 0.5%), under defined temperatures (25℃and 50℃) and incubation times (20 and 60 minutes) to establish a relationship between protein profile and food texture. Three different frozen shrimps (grass shrimp, prawn and lobster) were used as standards for comparison. The results show that the protein profile and scanning electron microscope of the three different frozen shrimps were slightly different. In plant proteins, the protein profile and texture were significantly affected with increasing TGase concentration, temperature and time of incubation. These three parameters had no effect on cyanobacteria and wheat proteins. In addition, it was found that soy and pea proteins after adding TGase had similar texture to frozen lobster. Experimental data indicate that adding 0.5% TGase to soy and pea protein could produce vegetarian shrimps with most similarity in protein profile and texture as lobster. Experimental data also show, that the flavor and springiness of food could be improved by using protein of cyanobacteria and wheat. In summary, this study may provide a database for preparing vegetarian shrimp.