CHEMICAL COMPOSITION OF WILD RICE GRAIN

Abstract

Twelve samples of Canadian lake and paddy wild rice (Zizania aquatica L.) were analyzed for proximate, mineral and amino acid composition. Mean proximate and mineral values for lake and paddy wild rice were: total carbohydrate 82.8%, protein (nitrogen × 5.7) 13.8%, ash 1.7%, crude fiber 1.2%, ether extract 0.5%, phosphorous 0.28%, potassium 0.30%, magnesium 0.11%, iron 17 ppm, manganese 14 ppm, zinc 51 ppm and copper 13 ppm. Amino acid composition of the unprocessed wild rice showed little variation among samples. The essential amino acid score of the unprocessed wild rice, based on the FAO/WHO 1973 pattern, was 82, with threonine and lysine most limiting. Lysine values were lowered by processing. Calculated nitrogen-to-protein conversion factors were 5.60 for Johnson strain and 5.65 for lake-grown wild rice.