PRODUCTION AND QUALITY CHARACTERIZATION OF PULP FROM COCOA BEANS FROM TRINIDAD: EFFECTS OF VARYING LEVELS OF PULP ON VALUE-ADDED CARBONATED COCOA BEVERAGES

Abstract

The cocoa industry in Trinidad and Tobago has experienced a steady decline in production of cocoa over the past 50 years. There is a need to add value to cocoa by developing downstream products such as cocoa beverages. While the cocoa pulp (mucilage), covering the seed coat (testa), has a crucial role in fermentation, if present in excess, it may also hinder the same process. The objectives of this investigation were therefore to develop an acceptable cocoa beverage using surplus cocoa pulp and (1) determine the difference in physicochemical (nutritional) properties between cocoa mucilage (pulp) and liquor made from cocoa nibs and (2) investigate the effects of adding varying amounts of mucilage (10 and 15 g per litre) with a standard quantity of liquor on the sensory acceptability and microbiological quality of carbonated cocoa beverages. Cocoa pods and dried and fermented beans were collected over a period of three months in 2012. The cocoa pulp and seed coat mucilage were extracted and freeze dried. The cocoa beans were made into liquor. Crude protein, % ether extract (crude fat), pH and micro nutrients, Cd, Cu, Na, Κ, Mn, Zn, Mg and Fe in the cocoa liquor and pulp were analysed. Two carbonated beverages were produced with varying levels of pulp (10 and 15g, respectively) and evaluated for sensory acceptance using a nine-point hedonic scale. Microbial analyses for total aerobic counts, yeast and molds, Escherichia coli, in the cocoa pod pulp and dried and fermented beans were conducted. Colour, pH and total soluble solids were measured on both the cocoa pulp and beverage. The data were analyzed using SPSS 16.There were significant differences (P <0.01) between cocoa liquor and cocoa pulp in crude protein and crude fat with cocoa liquor being significantly higher in both. Micro-nutrients of trace minerals showed a significant difference (P <0.005) between the cocoa liquor and pulp in six of the nine samples examined. Cocoa liquor had significantly higher ppm levels (wet wt) for trace minerals than cocoa pulp respectively for Fe (P<0.05: 11.97 vs 2.42), Zn (P<0.0001:25.19 vs 3.29), Na (P<0.01:81.46 vs 49.03), Κ (P<0.05: 2206.8 vs 853.10) and Mg (P<0.0001: 816.02 vs 153.67), but was lower for Mn (P<0.05: 0.66 vs 0.96). The pH of cocoa pulp was significantly lower (P <0.001) than that of the cocoa liquor. There was no significant difference in sensory qualities between the two cocoa carbonated beverages, which were both liked slightly in terms of acceptability. Microbial growth of 103 CFU/g was only observed on dried and fermented beans. A carbonated beverage with 10 grams of cocoa pulp per litre is recommended for commercialization in the food industry.