Kinetics of color development of peanuts during dry roasting using a batch roaster

摘要

The kinetics of color development during peanut roasting were investigated at roasting temperatures from 149 to 204 degrees C which produced Hunter L color values of 25-65. Preliminary and equivalent roasting trials were conducted using a batch roaster simulating the parameters of an industrial continuous belt roaster. Hunter L and b values of the roasted peanuts were fitted well to first-order models (mean R-2>0.93). The activation energy calculated from the first-order model of the L and b values ranged from 1.0 to 1.1 x 10(8) J/kg mol. High-temperature roasting decreased the uniformity of color development from seed to seed and throughout of the kernel. A z(c) value of 37.6 degrees C was calculated using the first-order model of the L values. The cook values were 11.5-23.6, 24.5-31.6, and 41.5-57.5 min for light, medium, and dark roasting, respectively.