Influence of fermentation time, drying time and temperature on cocoa pods (Theobroma cacao L.) marketability

Abstract

The technological variability of post-harvest treatments affects the product's cocoa beans marketability and stability, requiring knowledge of the conditions to be applied to the matrix in order to guarantee quality. With this in mind, the aim of this work was to find the optimum conditions for post-harvest treatments to obtain cocoa that complies with the standard in terms of moisture content, pH and graining rate. To achieve this, cocoa pods (Theobroma cacao L.) harvested in the Kekem locality were used to obtain cocoa beans after shelling. In order to identify the optimum post-harvest treatment process, the three process factors considered to be limiting, namely Fermentation Time (TF), Drying Temperature (TS) and Drying Time (TeS), were retained. A centred composite design was applied to these three factors to generate an experimental matrix of 20 trials on which the responses of moisture content, pH and grain rate were determined. These analyses show that the three responses were influenced (p˂0.05) by the treatment conditions. The pH fell significantly (p˂0.05) with increasing fermentation time, unlike drying time, which improved it. Moisture content was significantly (p˂0.05) reduced by drying time while it increased with fermentation up to 100 h. Graininess was significantly (p˂0.05) affected by fermentation time, drying temperature and the quadratic effect of drying temperature. The search for optimum conditions revealed that a 155 h fermentation and drying at 50.25 °C for 45 h resulted in beans that met the standard for moisture content (7 to 8 %), seediness (<100 beans/100 g) and pH (5 to 5.50). On the basis of this work, we recommend that cocoa farmers apply these optimum conditions in order to produce beans of good marketable quality while limiting losses.