Optimization of explosion puffing drying technology for Hami melon at variable temperature and pressure difference

A three factors quadratic regression rotation combination design was adopted to optimize the technology for explosion puffing drying of Hami-melon. Effect of three variable that are water content after pre-drying, puffing temperature and vacuum drying time on four indexes that are water content of product, crispness, puffing rate and color. Based on the experimental data, the quadratic regression model of four indexes was deduced, then variables were analyzed with response surface methodology(RSM). The optimal technical conditions were obtained as follows: water content after pre-drying is 30%, puffing temperature is 88～95℃ and vacuum drying time is 1.7～2.2 h.