Carrot root magnesium content on market of City of Zagreb

Mrkva predstavlja jednu od deset najvažnijih povrtnih kultura u svijetu. Korijen mrkve izrazito je hranjiv i bogat mineralima, pozitivno utječe na vid jer je bogat vitaminom A i beta karotenom. Magnezij je mineral koji pripada skupini makroelemenata i važan je za biljku jer je sastavni dio molekule klorofila. Nedostatak u biljci uzrokuje intervenoznu klorozu lista i žutu pjegavost. U ljudskom organizmu ima najvažniju ulogu kao regulator metabolizma kalcija i fosfora u kostima i za pravilan rad srca. Cilj ovog istraživanja je utvrditi količinu magnezija u narančasto obojenom korijenu mrkve te usporediti rezultate analiziranih uzoraka obzirom na mjesto kupnje. Uzorkovanje narančastog korijena mrkve provedeno je u gradu Zagrebu u 5 poslovnica trgovačkih lanaca, 5 tržnica i u 5 trgovina ekološkim proizvodima. Magnezij je nakon digestije koncentriranom HNO3 i HClO4 u mikrovalnoj peći određen atomskom apsorpcijskom spektrometrijom. Količine magnezija narančasto obojenog korijena mrkve iznosile su od 0,07 do 0,21% Mg ST, odnosno od 5,73 do 24,33 mg Mg 100 g-1 svježe tvari. Prosječno je najviše Mg utvrđeno u mrkvi iz trgovačkih lanaca.Carrot represents one of ten most important vegetable species. Carrot root is very nutritious and rich in minerals. It positively affects on vision because it is rich with vitamin A and beta caroten. Magnesium is a mineral which belongs to a group of macroelements and is important for the plant as it is the component part of the chlorophyll molecule. Lack of magnesium causes interveinal leaf chlorosis and yellow sprinkles. In human organism it has important role as calcium and phosporus regulator in bones and for proper heart functioning. Aim of this research was to determine magnesium content in orange-colored carrot root and to compare the results from the analyzed samples regards to the place of purchase. Sampling of orange carrot root in city of Zagreb was performed in 5 market chain branches, 5 market places and in 5 stores with ecological products. Magnesium was determined by atomic apsortpion spectrofotometry (AAS) after digestion with HNO3 and HClO4 in microwave oven. Magnesium content of orange colored carrot roots ranged from 0.07 to 0.21% Mg DM or from 5.73 to 24.33 mg Mg 100 g-1 fresh matter. Average the highest Mg content was determined in carrots from chain stores