Impact of roasting duration and temperature on the properties of fully fermented cocoa beans (Theobroma cacao L.)

The cocoa bean is one of the raw materials used to manufacture dark chocolate. Fermentation and roasting processes are needed prior to chocolate production. This research aimed to examine the physical characteristics of fully fermented cocoa beans with temperature and time of roasting as research variables. The roasting temperatures used were 140°C, 150°C, and 160°C. The durations were 25, 30, and 35 minutes. Roasting temperature affected the value of moisture content, acidity, hardness, and color of cocoa beans. Roasting time affected the hardness of cocoa beans. Hardness, moisture content, lightness (L*), and acidity (pH) of cocoa beans decreased with increasing temperature and roasting time. Redness (a*), yellowness (b*), chroma (C*), and hue (h) increased with the increasing of temperature and duration of roasting. Water content, hardness, acidity, lightness, redness, yellowness, chroma and hue angle values were in the range of 3.2-3.4, 3.47-4.87 N/mm2, 5.46 -5.81, 25.73-27.48, 8.38-11.13, 5.31-7.89, 9.94-13.1 and 31.77-41.23°, respectively.