Composition of tubers used by Hadza foragers of Tanzania

Data are presented on three edible species of tuber (Vigna frutescens, Emin ia entennulifa, and Ipomoea transvaalensis) consumed by Hadza foragers in n orthern Tanzania. These species are collected almost year-round by Hadza wo men but previous analyses of their macronutrient composition are variable a nd provide results based on the analysis of whole tuber. We examined only e dible portions of tuber by simulating chewing in the presence of salivary a mylase and by removing from analysis the typically expectorated inedible co mponent. Edible portions of the three peeled tubers ranged from 42.5 to 91. 8 g/100 g dry wt., were low in protein (2.3-6.9 g/100 g dry wt.), and conta ined 19.6-26.0 g/100 g of starch, The sum of monosaccharides and disacchari des ranged from 6.2 g/100 g in the Vigna frutescens to 48.3 g/100 g of edib le portion of Ipomoea transvaalensis. In addition, our analysis of 5 sample s of Vigna frutescens had a 5-fold range in energy available to consumers, an important consideration for energetic studies. This range was due, in pa rt, to the variation in edible portion (20.8-75.4 g/100 g of edible dry tub er). Our data, in comparison with those reported previously, show generally lower energy levels and higher levels of indigestible material for some of these tubers. These discrepancies are likely due to differences in analysi s of whole tuber versus edible portion, method of measuring indigestible ca rbohydrate, and age of tuber. (C) 2001 Academic Press.