Levels of chromium in Zimbabwean foods and its importance in carbohydrate metabolism

Abstract

Staple foods eaten by Zimbabweans were collected and analysed for their chromium content. Organic matter was destroyed by a wet oxidation procedure using concentrated sulphuric and nitric acids. The food digest was directly aspirated into atomic absorption spectrophotometer (AAS) models Varians AA-1275 and AA-5-275. The remainder of each digest had pentan - 2,4 dione added to it. The Cr complex formed was extracted in 4 methyl - pentan - 2 - one. Unfortunately no Cr was detected in the extract Water, leafy vegetables, naatjies (tangarines), oranges and beverage drink such as fizzy orange cordial and diabetic orange had either no Cr at all or only very low levels. Cr content in some fruits, such as bananas, apples and avocado pears, and in sweet potatoes and mealie-meal was moderate (mean 10,5 + 1,9 meg) as compared to cheese, groundnuts, cucumbers, maize on the cob, rapoko and meat products, such as liver, which were found to be rich sources of Cr. These ranged from 15,2 to 49,6 meg/g. The importance of dietary chromium in the metabolism of carbohydrates is also discussed.