Major, minor and trace elements composition of Amazonian foodstuffs and its contribution to dietary intake

Abstract

Nowadays the consumption of so-called superfoods and nutritional supplements represents a new growing trend in the field of human nutrition. It’s generally accepted that superfoods contain high levels of much-needed vitamins, essential fatty acids and minerals. Compounds of toxicological interest such as toxic elements could be also incorporated. Thus, the knowledge of the elemental composition and its dietary intakes are required for quality standards establishment of those superfood and related products. Several elements including major, minor and trace elements were analysed in selected foods (Brazil nut, golden berries, heart of palm and dietary supplements containing acai fruit) harvested in the Amazon region. Target elements were measured by inductively coupled plasma-mass spectrometry after a microwave assisted acid digestion pre-treatment. The accuracy of the proposed method were verified using Certified Reference materials and analytical recoveries tests. Ba, Ca, K, Mg and P (from 0.25 to 22387 µg g−1) are the major elements in selected samples. While Al, Cd, Co, Cr, Li, Pb and Sn (from < 0.01 to 3.02 µg g−1) are found at trace levels. Toxic metals (As, Be, Bi, Mo, Sb, Tl, V and W) concentrations in selected food samples are lower than quantification limits. Dietary element intakes were also, estimated and compared with recommended dietary allowances and upper tolerable levels. The distributions of the elements between lipid and lipid-free fractions of Brazil nut and golden berries were investigated. Element contents in the lipid fraction were lower than 1.8% and 8.4% for Brazil nut and golden berry, respectively.