Optimization of explosion puffing drying process of yam slice and study of its properties

ObjectiveExplosion puffing drying process for yam slices was optimized, its effects on microstructure and functional compounds of yam slices were investigated, in order to provide theoretical basis for actual production of high-quality yam slices. MethodWith rehydration rate, colour and shrinkage rate as evaluation indexes, puffing drying process was optimized using three-factor quadratic regression rotation combination design combined with fuzzy evaluation , and ef-fects of explosion puffing temperature (X1), vacuum drying temperature (X2) and time (X3) on quality of yam slices were analyzed. ResultResults showed that, the regression equation was established:Y=6.97-0.63X1-1.61X2-1.07X3+0.38X1X2-0.14X1X3+0.044X2X3-0.67X12-0.57X22-0.92X32(R2=0.9396, Y was comprehensive score), puffing temperature, vacuum drying temperature and time could affect significantly comprehensive score of yam slices(P<0.01). The optimal process-ing parameters were as follows: puffing temperature being 87 ℃, vacuum drying temperature being 74 ℃ and vacuum drying time being 138 min. Under the above optimum conditions, the rehydration rate, colour, shrinkage rate and com-prehensive score of yam slices were up to 1.82, 91.32, 36.12% and 8.71, respectively. The obtained yam slices were high-quality, and had good shape and reserved more flavonoids and allantoin. ConclusionIt is feasible that high-qual-ity yam slices is obtained using explosion puffing drying process optimized by quadratic regression rotation combination design, and the established regression model is suitable for practical production.