Mineral content in mustard leaves according to the cooking method

Abstract

This work evaluated the influence of the cooking methods (cooked in a water bath, in a stove, and in a microwave oven) on the mineral composition of mustard leaves (Sinapis alba). So, raw and cooked samples were digested and afterward the elements calcium, magnesium, potassium, sodium, iron, zinc, phosphor, barium and sulfur were determined using inductively coupled plasma optical emission spectrometry (ICP OES). The experimental work involved a set of five samples from different locations, processed in triplicates. The results were evaluated employing Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA) and Linear Discriminate Analysis (LDA). All techniques showed that the mineral content of the raw and cooked samples in a water bath is different from the samples cooked in stove and microwave oven. Especially for potassium, whose content is strictly controlled for chronic renal patients, this study showed that cooking using microwave oven has the greatest efficiency for reduction.

Keywords: Cooking methods; HCA; LDA; Microwave oven; Mineral composition; Mustard leaves; PCA; Varimax rotation.