Effects Of High-temperature On Quality Of Surimi Products

China is a big country of aquatic products and rich in fishery resources.Alaska Pollock,also known as Pollock,is a great ingredient in surimi products.At present,the circulation form of surimi products in Chinese market is too simple,which is not conducive to its long-term development.Taking Alaska Pollock surimi as the research object,the effects of high temperature treatment on the gel quality and flavor of surimi and its influence mechanism were discussed.And use the response to optimize the content of its added excipients,enrich the types of ready-to-eat surimi products,and provide certain theoretical support and technical guidance for its industrial production.In order to achieve the above research purposes:The paper mainly studies the following aspects:1.The quality and volatile components of surimi gel were studied after high temperature treatment.Using frozen surimi as raw material,the gel strength,whiteness,WHC and TPA index were determined,and the content of volatile flavor substances was determined by electronic nose analysis and gas chromatography-mass spectrometry(GC-MS).When the treatment temperature was 105?,the water holding capacity and texture characteristics of the surimi gel showed an upward trend.When the temperature continued to rise to 110?,the gel properties decreased significantly(p<0.05).It can be seen that 105? is suitable for surimi products.The heating temperature had no significant effect on the whiteness of the surimi gel and had a significant effect on the volatile components(p < 0.05).The surimi gel samples were detected at 100?,105?,110?,115? and 120?,respectively,37,46,49,52 and 56 compounds,these compounds mainly composed of aldehydes,hydrocarbons and a small amount of aromatic substances;The electronic nose can effectively distinguish the effects of five heat treatment temperatures on the gel odor of surimi.Heat treatment has an important effect on the gel properties and volatile flavor components of the surimi gel.2.The changes of chemical forces and secondary structure of protein in surimi gel after high temperature treatment were studied.Taking the Alaska Pollock surimi as raw material,the chemical interaction between protein molecules was determined.It was found that after heat treatment,the hydrophobic interaction and ionic bond decreased,and the hydrogen bond and disulfide bond content increased.Infrared(FT-IR)spectroscopy analysis showed that the random coil and ?-sheet were most damaged in the secondary structure of the protein with increasing temperature.The results of nuclear magnetic resonance showed that as the heat treatment temperature increased,the water became more active and the binding property decreased,which also caused the gel strength of the surimi to decrease.In addition,the surface of the sample treated at 115? and 120? was looser,the gap was larger,and there were larger pores,which led to protein aggregation and a marked decrease in gel strength.3.The thermal stability of modified starch,carrageenan and wheat protein was studied.Based on previous studies,105? has a good effect on the gel quality of surimi after high temperature treatment.Therefore,this paper studied the gelling properties of surimi products by three factors: modified starch content,carrageenan content and wheat protein content at 105?,and it is optimized by the response surface method.Adding modified starch,carrageenan and wheat protein can significantly improve the gel properties of fish sausage.The addition of 10% hydroxypropyl distarch phosphate sample had the highest gel strength;the whiteness and water holding capacity also increased with the increase of the addition amount;When the carrageenan content is 0.8%,the gel strength,water holding capacity and whiteness of the sample reach the highest in turn;When the protein content of wheat was 8%,the gel strength reached the maximum,and the whiteness decreased with the increase of the added amount.According to the optimization of response surface methodology,the optimal process for adding supplements to surimi products is: modified starch 9.0%;carrageenan: 0.8%;wheat protein 8.0%.Under this condition,the gel strength of surimi products is 605.18 g·cm.4.The quality characteristics of mixed surimi(Alaska Pollock,grass carp)gel with different proportions were studied.By measuring the gel strength,whiteness,water holding capacity,TPA index,and observing the microstructure by electron scanning microscopy,the results showed that the addition of the appropriate amount of grass carp surimi,the mixed surimi samples had the highest gel strength,but the proportion of grass carp surimi continued to increase.The gel strength of the mixed surimi samples decreased significantly,indicating that a certain proportion of mixed surimi and freshwater surimi can increase the gel quality of the surimi;the ratio of different salmon and grass carp surimi has no significant effect on the whiteness of mixed surimi samples;When the mixing ratio of grass carp and fish carp is 2:1,the mixed surimi gel has the highest water holding capacity and hardness.