Behavior of atmospheric variables in the traditional drying process of cocoa and its correlation with the humidity and acidity

Abstract

In order to determine the behavior of atmospheric variables that influence the traditional drying process of cocoa in Chuao, Venezuela; and its correlation with humidity and acidity was installed a digital weather station in the vicinity of the drying yard. Data were recorded on the variables temperature (° C), humidity (%) and solar irradiation (W.m-2). The measurements were made  at  15  min intervals.  Simultaneously 96 samples were taken in triplicate of the mass of cocoa of 20 g, every 20 min during the nine days of the process. They were identified and packaged in airtight bags and vacuum-sealed; then, they were kept in a freezer to guarantee the non-modification of their characteristics until the transfer to the laboratory for final moisture analysis and titratable acidity. Wheaterlink® software was used to analyze atmospheric variables and Curve Expert Basic 1.40 software to obtain trend lines, which are presented as polynomials, with their respective correlation coefficients (CR) and standard deviations (SD) for each variable. The temperature with DS = 0.416217 and  CR  =  0.9889267;  solar  irradiation  with  DS=30.287368 and CR = 0.993219 and ambient humidity with DS = 1.211358 and CR= 0.991878. The results for initial,  critical and final cocoa moisture  were50.93%; 30.37% and 6.96%, respectively; associated with a critical time of 380 min and dehydrated total of1900 min, with hygroscopic behavior of cocoa at night. The acetic acid content was between 0.84 - 0.98%. The correlation between atmospheric variables and humidity of the cocoa had a CR = 0.996363 and DS =1.131872.