Relationship between Viable Bacterial Counts and Physicochemical Properties of Cocoa Powders andPowdered Cocoa Beverages purchased in Nigerian Supermarkets

Cocoa powders (CPs) and powdered cocoa beverages (PCBs) are largely consumed as health and vitality drinks in Nigeria. In view of the recent reports that these food products supported bacterial growth, this study determined whether there could be definite relationship between viable bacterial counts and physicochemical properties of five brands of CPs and PCBs purchased from supermarkets in Ibadan and Lagos in South West, Nigeria. The pH and titratable acidity of the products were measured by using pH meter and colorimetric acidity titration respectively. The moisture contents were determined by drying method at 105oC in oven and ash by mineralization at 550oC using furnace. No definite type of relationship was established between viable bacterial counts and pH, titratable acidity (lactic acid, acetic acid), moisture and ash contents vis-a-vis powdery and granular natures of the cocoa food products. Only the two PCBs tightly packed in the polythene sachets had acceptable mean viable bacterial counts, which did not exceed 5.0 x 103 cfu/ml specified for cocoa powders in food industries. Also, only two of the five brands had acceptable moisture contents, which did not exceed the national specification of 3.10% for cocoa powders. Furthermore, the ash contents of all the brands exceeded the acceptable national specification of 2.60%. Significant variations (P<0.05) were obtained in the mean pH, titratable acidity, viable bacterial counts, moisture and ash contents within and between products containing only cocoa powders and those containing additives. In conclusion, the results from this study showed that the physicochemical properties of cocoa powders and powdered cocoa beverages could not be used to predict the viable bacterial counts of these food products.