Evaluation of the content of minerals and toxic metals and dietary fiber in plant products and their extracts

Abstract

The objectives of this work were (i) to learn about methods used in quantification of mineral elements such as the Zn, Cu, K, Na, Pb and Cd in food samples, as well as the methodology used in the quantification of the fiber, (ii) know the principal laboratory procedures of the chemical analysis of food and (iii) interpret the results obtained relating them with possible effects on human health. Thus, in the first part of the work presents an approach to fundament and applications of atomic absorption spectrophotometry for the quantification of mineral elements and methodology for the valuation of crude fiber in foods. They are also referred to the main effects of mineral nutrients and fiber in human health. Was verified that the method of atomic absorption presents a good precision of results regarding the concentration of minerals in food samples. However, the levels of lead and cadmium in some samples exhibit a low accuracy, there was a necessity to assess the origin of this variability. The samples Demonstrate contents of mineral elements K, Na, Cu, Zn, Pb and Cd, which Conducted to ingestion within the intervals considered adequate for human health. Relatively to partition between the husk and endosperm of the mineral elements in seed samples was observed that the potassium accumulates in the endosperm, whereas the other elements analyzed minerals (Na, Cu, Zn, Pb and Cb) accumulate mainly in the husk. Also, the fiber shows a similar behavior concentrating mainly on grain husk of Fagopyrum esculentum (buckwheat or buckwheat) having high levels of fiber. It was observed that the Cu content of the cocoa has relatively high values and may result in a daily intake which exceeds the values considered suitable for human health.