Empirical Modeling of the Effects of Magnetic Field Pretreatment on the Drying Rate of Sweet Pepper and Fluted Pumpkin Leaf

Abstract

Empirical modeling of the effects of magnetic field pretreatment on the drying rate of sweet pepper and fluted pumpkin leaf was done. Static, pulse and alternating magnetic fields were used in conjunction with magnetic field strength (5 - 30 mT) and pretreatment time (5 - 25 min) as the combined pretreatment factors. All samples were dried at 50 °C after pretreatment and the drying rate was estimated. Data obtained were used to produce bar charts that showed statistical effect of magnetic field pretreatment on the drying rate. Same set of data were also used to develop empirical model equations. Results showed that most of the magnetic field pretreatment combinations caused the drying rate of SP (20 - 21 g·h-1) and FPL (10 - 12.50 g·h-1) to be significantly higher than the drying rate of blanched samples of SP (17 g·h-1) and FPL (8 g·h-1) at P ≤ 5%. Also, there are six (6) empirical model equations that reliably described the characteristics of the process with R2 (88 - 98 %); R2 adj (83 - 95 %); coefficients of variation (0.88 - 3.80); standard error (0.11 - 1.07); mean of residuals (-0.0008 - 0.0002); standard deviation (0.16 - 1.19); probability values (0.0000 - 0.0007) and adequate precision values (6.80 - 25.46).