Researching On The Processing Technology And Storage Characteristic Of Fried Carp

Fried carp is a way of deep processing of crucian carp which has attractive color and unique flavour,so it is populour by the people of all ages.But the oil content of traditional fried carp is high,which not only shortens its shelf-life,but also influences the health of human and hinders its industrialization.In this study,fried carp is selected as research object.First of all,optimizing parameters of the curing process of fried carp.Second,It explores the influence of drying process,soybean protein isolated,guar gum and sodium carboxymethyl cellulose which have different mass fraction and frying process on the oil content and quality of fried carp.Then combined with the response surface experiment which is for the purpose of studying the better method of lowing oil content of fried carp.In addition,storing fried carp under different temperature,using dynamic model which is based on temperature to predict the shelf life of fried carp.Based on ensuring flavour,taste,appearance and reducing the oil content of fried carp,it provides certain theoretical basis and pratical guidance for fried carp's processing,production and the prediction of shelf-life.The main results were as follows:(1)Curing process has a certain impact on the quality of fried carp.Factors which influence the quality of product contain the addition of salt,cooking wine,hot peppers,spring onions and curing time.Making sensory score as the index,through the poor and orthogonal analysis of orthogonal experiments(L₉(3⁴)),it concluded that the primary and secondary factor was C(amount of hot pepper added)=D(amount of spring onion added)>B(amount of cooking wine added)>A(amount of salt added).The appropriate curing process is:the adding amount of salt,cooking wine,hot peppers,spring onions is3%,4%,25%,15%respectively.In this process,the sensory score of fried carp is 86.4.At the same time,it concluded that the best curing time is 24h.(2)Drying process,the types and quantity of edible film,frying process all have certain influence on oil content and quality of fried carp.On the basis of single factor experiment,designing the response surface experiment which use oil content as the index,through analysis of variance,curve of the response surface and contour map of response surface methodology,from which concluded that the influence of various factors on the oil content of fried carp whose order are:B(mass fraction of guar gum)>A(drying time)>C(frying temperature)>D(frying time).By solving regression equation,the best processing parameters of reducing the oil content of fried carp is:drying time is 8h,the mass fraction of guar gum is 1.3%,frying temperature is 175?,frying time is 4.15min.At the same time,the best composition of wrapped slurry is:wheat flour is 100%,low sodium salt is 1%,edible alkali is 0.5%,guar gum is 1%whose mass fraction is 1.3%.Finally,flour:water=1:1.8(wheat flour accounted for 30%of the dried fish base).In this process,the oil content is 5.67%and sensory score is 87.5 of fried carp,Compared to the oil content of 22.41%and sensory score of 75.6 of fried carp which are not capsuled,it significantly reduced the fried carp?s oil content,and the color,flavor,taste is good.(3)In the range of storage temperature(4?,20?,25?,35?and 45?)which is researched,with the extension of storage time,the L value of fried carp decreased,but p H value,TBA value and peroxide value increased.With the increase of storage temperature,the change rate of these values increased.Using pearson correlation coeffient to analyse the correlation of sensory scores and other various indexes(L value,p H value,TBA value and peroxide value)which are measured under 4?.The correlation coeffient is 0.9185,-0.9777,-0.9873,-0.9798 respectively.From this,choosing TBA value and peroxide value whose correlation with product quality are stronger.Using the parameters of TBA value and peroxide value to make linear and nonlinear fitting respectively.From the decision coefficient,it can conclude that the quality change of fried carp more conform to the zero-order kinetics model than the first-order kinetics model.In addition,compared with the?R²=4.98219 of peroxide value,the R²=4.99889 of TBA value is bigger.So the shelf life prediction model of fried carp which is based on choosing TBA value as the index.Namely using rate constant K_a(y):0.01224?0.02184?0.03722?0.03852?0.07554and 1/T(x):1/277K?1/293K?1/298K?1/308K?1/318K to making figure.Through calculating the regression equation,obtaining the former factor is K₀=2.6664×10⁴,activation energy E_A=33.92 k J/mol.So the model formula is expressed.By this model,obtaining the shelf life were 95.26d,42.62d,33.74d,21.63d,14.26d which were storage at 277K,293K,298K,308K,318K,compared to actual value 90d,42 d,32 d,20 d,14 d whose error is 5.84%,1.48%,5.44%,8.15%,1.86%which are in the range of error,so it can be used to predict the shelf-life of fried carp which in the range of some temperature.