Dynamic and static drying temperatures for ‘Barton’ pecans: Impacts on the volatile compounds profile and kernel color

Abstract

This study aimed to verify the effects of ambient, static, and dynamic drying temperatures on the volatile compounds (VC) profile and color preservation of ‘Barton’ pecan kernels. The static temperature of 60 °C used to dry the pecans to the desired moisture content (4.5%) reduced the drying period by 44.4 times compared to ambient drying conditions, as a combined effect of the higher temperature and lower air relative humidity (RH). Although, this drying condition increased aldehyde and ketone levels. Drying under ambient air conditions produced the best color parameter (greater hue angle) after drying, although without differing from 60 °C. Drying with a static temperature of 40 °C resulted in the lowest hue angle, and the static drying temperatures of 40 or 60 °C increased total aldehyde production. Our findings showed that the dynamic drying temperature of 40↔60 °C is recommended for ‘Barton’ pecans due to the lower color change, aldehyde and ketone abundance, and shorter drying times (22.2 times more efficient than ambient drying).