PL
W kawach naturalnych mielonych i ziarnistych po zmieleniu oraz w naparach wykonanych z tych kaw oznaczono zawartość wapnia, magnezu, niklu i chromu metodą atomowej spektrometrii absorpcyjnej. Określono również stopień ekstrakcji do fazy wodnej dla każdego z oznaczanych pierwiastków. Wyniki poddano analizie statystycznej za pomocą programu Statistica.
EN
Calcium, magnesium, nickel and chromium contents of some natural ground coffee grades, coffee beans and coffee infusions were determined by atomic absorption spectrometry using a Pye Unicam SP 192 unit. Various commercially available coffee grades were tested. The extraction degree (per cent extracted to the infusion) was determined for each examined element. The mean values were: Ca 40.4%; Mg 62.2%; Ni 37.4% and Cr 67.6%. The concentration (mg/kg) ranges for the natural coffee were: Ca 1312.50 to 2550.00; Mg 1750.00 to 3000.00; Ni 0.45 to 4.93; Cr 0.20 to 0.75. Coffee infusions contained from 28.00 mg to 53.75 mg Ca, 53.13 mg to 96.88 mg Mg, 0.011 mg to 0.093 mg Ni, and from 0.008 mg to 0.028 mg Cr per one cubic dm of the infusion liquid. Our results are comparable with data by other authors. A significant relationships was detected between the levels of the examined elements in coffee infusions and in coffee beans.