Investigating Kernel Moisture Content at the Front and Back of Semitrailers during Peanut Drying

Abstract. The effectiveness of peanut drying can be influenced by many factors. Such factors include temperature and relative humidity of the air used for aeration, air velocity through the peanuts, and any obstructions to air flow caused by foreign material. Therefore, it is highly unlikely that a semitrailer holding 20 to 25 tons of peanuts will dry uniformly. During the drying process, an operator removes samples of peanuts for kernel moisture testing every three hours or so. Such testing is often used to validate the estimated drying time determined by peanut-drying models used in the peanut industry. However, if samples are taken only from one location, it is likely that other locations have higher or lower kernel moisture contents. To investigate kernel moisture content at the front and back of the trailer, two peanut drying monitoring systems were deployed at a peanut buying point in central Georgia. Each system monitored drying parameters and in-shell kernel moisture content in real-time, every 12 seconds. In-shell kernel moisture content was determined with a standard error of prediction of 0.55% moisture when compared to the reference oven-drying method. They were placed in 45-ft (13.7-m) drying semitrailers, one 10 ft (3 m) from the front and the other 10 ft (3 m) from the back. Data from the measurements were time-stamped and reconciled accordingly, and they were analyzed to compare the moisture loss in real-time at both locations in the trailer. The 12-second resolution provided a continuous moisture profile to analyze rather than the discrete profile usually provided by sampling every few hours. Results show that moisture loss, and therefore resulting kernel moisture content, is variable from one end of the trailer to the other in some cases. Therefore, systems that monitor peanut drying at various locations throughout the semitrailer would improve peanut drying efficiency.