Determination of Sugar and Some Trace Metals Content in Selected Brand of Fruit Juices

Abstract

Ten brands of commercial fruit juices were analyzed for pH, specific gravity, total solids, reducing sugar and total sugar trace metals contents. The pH was determined using a Hanna pH meter. Sugar content was determined using the Lane and Eynon method. Sodium and potassium were determined by flame photometry while calcium and magnesium by complexometric titration using EDTA and the other metals were determined by atomic absorption spectrophotometry. The fruit juices were found to have a pH range of 1.80 – 3.50, specific gravity of 1.001 – 1.053, total solids of 0.68 – 12.49 %, reducing sugar content of 0.36 – 8.24 % and total sugar content of 0.52 – 10.09 %. Metal content of calcium (0.01 – 1.25mg/L), magnesium ( 0.06 – 0.42mg/L), sodium (0.84 – 3.11mg/L), potassium (0.16 – 7.42mg/L), copper (0.26 – 5.06mg/L), zinc (0.01 – 0.10mg/L), chromium (0.03 – 0.09mg/L), manganese (0.11 – 6.96mg/L), cobalt (0.01 - 0.08mg/L), nickel (0.03 – 0.15mg/L), iron (0.45 – 0.50mg/L), cadmium (0.14 – 0.38mg/L), and lead (0.02 – 0.32mg/L). The Nigerian made juices had higher amount of added sugar. The Nigerian pineapple juice brand had very high concentration of iron and the presence of cadmium and lead in some of the samples is an indication of contamination. However the contamination level does not pose health threat to the consumers.

Keywords: Fruit Juice, Reducing Sugar, Sugar Content, Trace Metals