| Pumpkin is the main research objects in this study.To explore the optimal conditions of enzymatic hydrolysis,pectinase and cellulose were used to enzymolyse pumpkin pulp,filtration the Pumpkin Pulp under the optimum condition,than use spray drying process to obtain the instant pumpkin powder and the Pumpkin pomace use hot air drying process to obtain the Pumpkin pomace powder.In addition,the nutrition components of the both,the instant of the instant pumpkin powder,the productand properties of deep fried pumpkin cake.The main results were as follow:1.Base on the soluble solids content of pumpkin plup,though single factor and orthogonal experiments,the effects of Enzymatic hydrolysis temperature,enzymatic hydrolysis p H and enzyme activityon pectinase enzymolysis pumpkin pulp were investigated.The results showed:pectinase enzymolysis temperature 40?,p H 4.0,amount of enzyme added was 0.20%,the amount of enzyme soluble solids content is the highest.2.Base on the soluble solids content of pumpkin plup,though single factor and orthogonal experiments,the effects of Enzymatic hydrolysis temperature,enzymatic hydrolysis p H and enzyme activity on cellulase enzymolysis pumpkin pulp were investigated.The results showed:cellulase enzymolysis temperature 40?,p H 4.5,amount of enzyme added was 0.03%,the amount of enzyme soluble solids content is the highest.3.Instant pumpkin powder and pumpkin pomace prepared by Enzymatic Hydrolysisrich in nutrition.Pumpkin powder vitamin E content was 9.2 mg / 100 g,beta carotene pigment content was 174.84 mg / 100 g,pumpkin pomace in vitamin E content was 20.33 mg / 100 g,beta carotene content was 57.63mg/100 g,Pumpkin powder Ca,Mg,Zn,Fe content were170.80mg/100 g,98.11 mg/100 g,11.07 mg/100 g,39.71 mg/100 g,Ca,Mg,Zn,Fe content of pumpkin pomace were 149.3 mg/100 g,63.59 mg/100 g,1.75 mg/100 g,5.96 mg/100 g.The instant pumpkin powder spray dried was reconstituted good,fast wetting,dispersing quickly,good solubility,and its solubility can up to 71.93%.4.Based on single factor and orthogonal experiments,the effects of frying temperature,frying time,moisture content and the ratio of glutinous rice flour to pumpkin powder on the texture profile analysis(TPA)and sensory evaluation of frying pumpkin pie were investigated.The experimental results showed that the optimum processing conditions for fried pumpkin pie were as follows: frying temperature 150?,frying time 6min,moisture content 80%,the ratio of pumpkin powder and glutinous rice flour 1:4;With increasing temperature frying,frying time extended,the increase of proportion of glutinous rice flour,pumpkin cake offriability and hardness showed rising trend;with the increase of moisture content,pumpkin cake of friability and hardness showed downward trend.5.By kinetic analysis,X-diffraction analysis,differential scanning calorimetry analysis and in vitro digestibility analysis,the heat transfer characteristics,structural changes and digestive properties of fried pumpkin pie was studied.The results showed that: fried pumpkin pie heat transfer in line with first-order kinetics;compared with glutinous rice flour,the diffractograms of the fried sample showed peak shifting and the diffraction peak decreased,which indicated the crystallinity decreasing after fried,the crystallinity for the crust,middle and center of pumpkin pie were 4.46%,3.86% and 3.07%;The higher moisture content,the phase transition temperature was lower,the enthalpy was higher,after fried the heat enthalpy of fried pumpkin pie was decreased;After frying,the content of RDS decreased significantly,and the content of SDS and RS increased significantly compared with Glutinous rice flour. |
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