Abstract:

Technological process and mathematical model of hot-air thin layer drying for fresh-cut lotus roots were systematically investigated using single factor and orthogonal test through SPSS12.0 analysis. Results indicated that the optimal technological condition for drying fresh-cut lotus roots slices was 70 ℃ of hot air, 0.3 m/s of hot air rate, and 40 g of loading amount. Under this optimal condition, drying rate, iodine-blue value, whiteness and water-holding capacity reached the perfect level. A mathematical model had been established and expressed with the equation MR = 0.8574exp(－0.0501t) (R2 = 0.9654) through SPSS12.0 analysis. The speculated results using this mathematical model were in good agreement with the determined results, which suggested that this mathematical model could be applied to demonstrate the process of hot-air thin layer drying for fresh-cut lotus roots.

Key words: fresh-cut lotus root, hot-air thin layer drying, drying curve, mathematical model