Research On The Processing Optimization And Quality Evaluation For Explosion Puffing Dired Peach Chips

Fresh peaches were chosen as the test materials to obtain49varieties of peach chips, which were produced by the technology of Explosion Puffing Drying. In the study, the core evaluation indexes were selected from15quality evaluation indexes, which concluded organoleptic quality indexes, physicochemical and nutrition indexes and processing quality indexes. Meanwhile, experimental quality indicators data was analyzed by Analytic Hierarchy Process (AHP) method and the quality evaluation models were established. The aims of the study were to provide theoretical evidence and guidance for quality evaluation on peach chips and processing suitability of peach materials.Through the research of the peach explosion puffing drying technology and the establishment of peach chips quality evaluation system, the conclusions can be summarized as follows:1. The pre-treatment conditions were:the pre-drying temperature was80℃, the color-protecting reagent was2.5%citric acid solution, the dipping reagent was25%maltitol solution.2. The appropriate values of the process parameters were obtained by the single factor experiment, the response surface method and frequency analysis. The pre-drying times was3.08-3.68h, puffing temperature was77.80℃～86.17℃, and vacuum drying time was2.23-2.50h.3.15quality evaluation indexes were chosen from organoleptic quality, physicochemical and nutrition properties, and processing quality. The core quality evaluation indicators were screened according to principle component analysis (PCA) and cluster analysis. The core indexes of yellow peach chips were soluble solid, rehydration ratio, the value of "a" and crude fat; the core indexes of white peach chips were titratable acid, soluble solid, the value of "L" and crude protein; the core indexes of nectarine were reducing sugar, output ratio, the value of "a" and crude protein; the core indexes of flat peach chips were the value of "L", water content, titratable acid, output ration and the value of "a"4. Based on the AHP model, the comprehensive scores (Y) of peach chips could be calculated by the following equations:The mathematical model of yellow peach chips was:Y1=0.1007x soluble solid+0.0724×rehydration ratio+0.3757×"a"+0.0287×crude fat+0.4225×"L". The mathematical model of white peach chips was Y2=0.3514×"a"+0.1716×titrable acid+0.0964×soluble solid+0.3514×"L"+0.0291×crude protein. The mathematical model of nectarine chips was Y3=0.2133×reducing sugar+0.1285×output ratio+0.3135×"L"+0.3135×"a"+0.0312×crude protein. The mathematical model of flat peach was Y4=0.2820×"L"+0.1619×water content+0.1756×titratable acid+0.0985×output ratio+0.2820×"a"According to the maturity scale and actual situation of the samples,4type peaches were chosen for the sensory evaluation and fitting test. The result of fitness for AHP model showed that the relational indexes between sensory evaluation results (X) and AHP predicted values (Y) were greater than0.90, which means the AHP model fit the mathematical model well, and the mathematical model could be applied in the peach chips quality evaluation.