Study On The Effect Of Gelatin And Mechanical Properties Of Daylily Tofu On Its Processing Technology

Due to the high organic matter content in the soil of Ningxia Daylilies,abundant sunshine and other advantageous conditions,the flower buds of Ningxia Daylilies are not only fat,good appearance,but also rich in nutrition,so the dried products are popular among consumers;in recent years,with the continuous expansion of its planting scale the output is increasing year by year,and it is urgent to solve its single product and improve economic benefits through deep processing;this article combines day lily with the popular tofu to carry out research on the processing technology of day lily tofu and optimize the technology;especially for the main processing stage the influence of soybean milk,tofu gel and tofu on the quality has been deeply discussed.This research not only explores a way for the deep processing of daylily,but also increases the nutrition of tofu and enriches its varieties.The main research contents are as follows:(1)To study the effects of different coagulants(gluconate-α-lactone(GDL),magnesium salt(MgCl2)and gypsum(CaSO4))on the quality of tofu,and use hardness and sensory scores as response values to establish quadratic polynomial regression model,response surface optimization,get the best combination parameters of coagulant:GDL addition amount is 0.3%,MgCl2 addition amount is 0.4%,CaSO4 addition amount is 0.6%,and the solidification temperature is 85℃.The tofu with moderate hardness,uniform color and good quality is obtained.(2)To study the effects of different processing methods of day lily(day lily powder,day lily section,day lily juice)and different addition amounts on the size of day lily soy milk particle size,centrifugal precipitation rate,product yield,sensory score;the results show:The particle size distribution of soybean milk added with daylily powder is relatively stable.When the addition amount is 5g,the average particle size(D[4,3])is at least 0.72μm,and the distribution range is 0.11～9.24 μm;The centrifugal precipitation rate,yield and sensory score of day lily soymilk were comprehensively evaluated.When day lily juice was added at 1:10(v/v),the Ci value of day lily soymilk was the largest(0.9481),indicating that its comprehensive quality was the best.The texture,rheology and gel strength of different day lily tofu gels were studied.With the increase in the amount of day lily,the hardness and gel strength of the three day lily tofu gels increased significantly(p<0.05),the elasticity and resilience are reduced;when the addition amount of daylily juice is 1:10(v/v),its gelation is better,and the gelation gradually decreases with the increase of the addition;3 types The G" of tofu gel increased,and G’>G".The change of the tofu gel of daylily juice was more obvious,indicating that the addition of daylily juice can significantly improve the gel property of tofu.(3)A comparative study of daylily powder tofu,daylily segment tofu,and daylily juice tofu in terms of protein secondary structure,rheological properties,texture properties,sensory scores,yield,water retention,color difference and so on.The results showed that the protein stability of tofu in daylily juice is better,and the content of β-sheet structure is the largest,accounting for 39.8%;the gel strength and hardness of tofu in daylily juice are significantly different from the other two kinds of tofu(p<0.05);three kinds of tofu fracture stress(б)size order is day lily powder tofu>day lily juice tofu>day lily section tofu,yield strain(ε)size order is day lily section tofu>day lily juice tofu,get the yellow flower Vegetable juice tofu has the strongest gel strength.(4)Electronic nose detection and PCA principal component analysis show that the total contribution rate of the two principal components is 99%,and the principal component of the sample is highly reliable.The electronic nose radar fingerprint map shows that the characteristic values of W5S,W2W,W2S,W1W,W3S and W6S sensors are day lily tofu>day lily powder tofu>day lily juice tofu.All three types of day lily tofu have an effect on nitrogen and oxygen compounds.Methyl compounds are sensitive,indicating that the addition of day lily can increase the flavor and taste of tofu to a certain extent.Analyzing the nutritional components of different tofu using the principal component of reducing dimensionality,it is found that there is little difference between the three kinds of tofu.Observing the microstructure of the three kinds of tofu,it is found that the tofu with daylily juice has a tighter structure,smaller pores,and a smooth section than the other tofu.