Effects Of Potato Starches And Transglutaminase On The Functional Properties Of Common Carp Myofibrillar Protein

In the paper, the effects of different concentrations and heating temperatures of potato starches (0,1,2,3and4%;60,70and80℃) and transglutaminase (0,0.10,0.30,0.50,0.70%;60,70and80℃) were investigated by determination of turbidity, emulsifying propertities and gel properties (TPA, whiteness, water-bolding capacity) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of myofibrillar protein. Meanwhile, the combined action of potato starches with transglutaminase was investigated. These results will provide theroretical basis to freshwater fish deep processing, products quality improvement. Deep processing and improvement products quality of freshwater fish were carried out on the basis of obtained results. The results were as follows:1. The effect of potato starches on MP functional properties of the common carpWith the same temperature, increasing potato starches addition lead to turbidity significant increase (P<0.05); and also, with the same potato starches content, increasing heating temperature lead to turbidity significant increase (P<0.05). With the increasing potato starches addition, the EAI and ESI decreased firstly, then increased, and decreased finally. EAI and ESI reached to maximum25.66m2/g and90.67%by adding2%and1%potato starches, respectively.With the same adding level of potato starches, the hardness and springiness of myofibrillar protein gel at80℃were higher than those at60and70℃significant(P<0.05); Under the same temperature(60℃、70℃and80℃), the hardness and springiness of gel with addition4%potato starches reached the maximum at the same time. And hardness and springiness reached maximum48.07g、0.81, by adding4%potato starches at the80℃. Under the same temperature, whiteness decreased slowly as the concentration of potato starches increased, whiteness at80℃was loweast compared with60and70℃(P<0.05). Meanwhile, water-holding capacity increased with increasing potato starches concentration, under the same adding level of potato starches, water-holding capacity at80℃was higher than water-holding capacity at60℃,70℃significantly (P<0.05),water-holding capacity at80℃increased significantly than60and70℃(P <0.05), under the80℃temperature, water-holding capacity reached the maximum96%by adding4%potato starches.2. The effect of TG on myofibrillar protein functional properties of the common carpUnder the same TG content, turbidity increased significantly with increasing temperature (P< 0.05). Under the same temperature, turbidity declined with increasing adding level of TG, the turbidity was the maximum when TG content was0.5%. With the increasing adding level of TG, EAI increased then decreased gradually and ESI decreased then, increased Moreover, EAI reached maximum18.87m2/g while TG adding level was0.5%; ESI reached maximum88.85%while TG adding level was0.7%.The gel hardness and springiness increased gradually with increasing adding level of TG, it suggested that TG could improve MP gel profile significantly. The gel hardness and springiness at80℃increased significantly than60and70℃(P<0.05). With the increasing adding level of TG, the whiteness increased, and then decreased, under the different heating temperature (60,70and80℃). The whiteness of gel with0.3%TG reached the maximum78.16, under the80℃. Water-holding capacity increased with increasing adding level of TG. When the adding level was0.5%, water-holding capacity reached the maximum90.43%, under the80℃.3. The effect of potato starches and transgluminase on MP functional properties of the common carpWith the increasing adding level of potato starches and TG, EAI decreased gradually. The EAI of MP gel with3%and0.3%potato starches were the same to those with2%and0.5%TG..However, the ESI increased with the increasing adding level of potato starches and TG, ESI reached maximum94.47%when potato starches and TG adding level were2%and0.5%, respectively.Under the same temperature (60,70and80℃), the gel hardness and springiness increased gradually with increasing adding level of potato starches and TG. The gel hardness and springiness at80℃increased significantly than60and70℃(P<0.05), and When the potato starches and TG adding content were3%and0.5%, the gel hardness and springiness reached the maximum51.37gand0.86respectively. Under the same temperature (60,70and80℃), the gel whiteness increased with the increasing adding level of potato starches and TG; The gel whiteness at70℃increased significantly than60and80℃(P>0.05). Meanwhile, with the increasing adding level of PS and TG and temperature, water-holding capacity increased. Under the temperature of80℃, the gel water-holding capacity reached maximum96.31%, while potato starches and TG adding content were4%、0.5%, respectively. NMR T2relaxation measurement results of myofibrillar protein gel under80℃showed that there were mainly two kinds of water in the gel, according to the two peaks in relaxation time figure. The three-dimensional mesh structure of gel was more compact, and the peak area of peak T22increased. At the same time, the water-holding capacity also increased, indicating that this kind of water contribute to increasing water-holding capacity.