Using two methods for plant material preparation in order to determine the content of bioelements in red cabbage (brassica oleracea l. var. capitata l. f. rubra)

Mineral components (bioelements) are one of the five major groups of nutrients in human diet, next to proteins, lipids, carbohydrates and vitamins. The required daily amounts per capita are over 100 rag of macroelements and less than 100 mg of microelements. Every industrial processing technology applied to vegetable produce causes precipitation of bioelements and consequentfy undesirable losses of these components. The purpose of this study has been to analyze the content of bioelements (Ca, Mg, Zn, and Fe) determined in homogenizates and extracts from three red cabbage cultivars (Koda, Haco POL, Kissendrup SWE). Correlation coefficients served to assess the concordance between the plant material preparation methods used for determination of bioelements. The correlation between the content of Mg versus Ca and Zn versus Fe in edible parts of cabbage (homogenizates) compared to the levels of these metals in red cabbage extracts was tested. Two methods for the preparation of plant material for chemical analyses were used: homogenization and extraction. Citric acid solution of the concentration of 0.1 mol dm(-3) was used for extraction. The content of bioelements was determined using atomic absorption spectrophotometry (AAS).