Abstract

This study aims to compare the impact of cocoa beans drying in the Microwave Oven (MO) and that made in the sunshine. This was to make 4 sets of drying tests through two devices: 30 samples for the solar drying (on tray) and 90 samples in the MO in the ratio of 30 samples per power levels (2400W, 2800 W and 3200W). Chemical parameters of quality were used for the comparative study. At the level of the volatile acidity parameter, the following value are recorded for the tray (0.62±0.03), MO 3200W (0.63±0.02), MO 2400 W (0.85±0.04) and MO 2800W (0.79±0.01). The values obtained are half less than that of the batch acceptability criteria (1-1.5 mL of 0.1N NaOH per gram of cocoa powder). The tray values (1.25±0.03); M.O 3200 W (1.25±0.03); MO 2400W (1.62±0.04) and MO 2800W (1.58±0.07) were noted for the free fatty acid test. They are smaller than the proscribed limit (1.75% of FFA oleic). Concerning the pH, are recorded for the tray (5.02±0.05) and 4.85±0.07; 4.72±0.05; 4.67±0.02 by power level assessment in the microwave oven. Only the values of dried beans on tray and MO 3200W are satisfactory. Total acidity obtained are: tray (5.47±0.02), MO 3200W (5.48±0.01), MO 2400W (5.25±0.01) and MO 2800W (5.32±0.01).

Keywords:

Cocoa beans , drying , microwave oven,

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