Determination of Heavy Metals in Cocoa Products Consumed in Nairobi County Kenya

Abstract

Cocoa is an important cash crop obtained from the beans of the Theobroma cacao tree belonging to the family Malvaceae. Its products are rich in several classes of phenolic compounds such as Flavanols, procyanidins, and anthocyanins. These compounds are attributed to copious health benefits. In addition to the bioactive compounds, cocoa contains heavy metals whose origin and levels depend on natural and anthropogenic activities. Beyond permissible limits, these metals are linked to deleterious damage to several systems in the human body. This study aims to determine the concentration of some heavy metals in Cocoa products and compare the levels with the permissible exposure limits stipulated by international health agencies. This was achieved by wet digestion of the strategically sampled cocoa products and their analysis using the atomic absorption spectrometry technique. The average concentration of Lead (Pb), Copper (Cu), Zinc (Zn), and Manganese (Mn) in cocoa powder was 0.154±0.021, 0.270±0.037, 0.794±0.063, and 0.334±0.015 respectively. The average concentration of Pb, Cu, Zn, and Mn in cocoa butter was 0.329±0.008, 0.028±0.038, 0.116±0.075, and 0.124±0.008 respectively. The average concentration of Pb, Cu, Zn, and Mn in chocolate milk was 0.463±0.003, 0.042±0.066, 0.296±0.015, and 0.162±0.010 respectively. Cadmium levels were below the detection limit in all the samples. The results obtained in all the samples were within the WHO and KEBS permissible levels in food products.