Sažetak | Grah mahunar (Phaseolus vulgaris L.) je jednogodišnja zeljasta biljka iz porodice mahunarki (Fabaceae). Plodovi graha mahunara visoke su nutritivne vrijednosti i predstavljaju izvor osnovnih hranjivih tvari, uključujući minerale, a potrošači prilikom kupnje nemaju informacije o njihovom mineralnom sastavu. Cilj ovog istraživanja bio je utvrditi količinu pojedinih makroelemenata u plodu graha mahunara koji je dostupan na tržištu grada Zagreba. Uzorkovanje je provedeno na tri tržnice, u tri trgovačka lanca te u tri trgovine ekološkim proizvodima. Plodovi graha mahunara osušeni su na 105 °C, nakon čega su usitnjeni i homogenizirani. Dušik je određen prilagođenom Kjeldahlovom metodom, te nakon digestije koncentriranom HNO3 i HClO4 u mikrovalnoj peći fosfor je određen na spektrofotometru, kalij na plamenfotometru, a kalcij i magnezij atomskom apsorpcijskom spektrometrijom. Suha tvar (ST) u uzorcima ploda graha mahunara kretala se od 8,18 do 10,38%. Utvrđena količina makroelemenata u suhoj tvari mahuna iznosila je 3,71% N ST, 0,45-0,47% P ST, 2,19-2,87% K ST, 0,29-0,34% Mg ST te 0,37-0,7% Ca ST. Vrijednosti u svježoj tvari iznosile su: 307,84-379,04 mg N/100 g svježe tvari, 37,97-47,94 mg P/100 g svježe tvari, 197,81-225,79 mg K/100 g svježe tvari, 27,59-32,69 mg Mg/100 g svježe tvari, 36,97-66,42 mg Ca/100 g svježe tvari. |
Sažetak (engleski) | French beans (Phaseolus vulgaris L.) are annual herbaceous plants belonging to the legume family (Fabaceae). They have high nutritional value and serve as a source of essential nutrients, including minerals. When purchasing, consumers lack access information about their mineral composition. The aim of this research was to determine the quantity of specific macroelements in the French beans available on the market in the city of Zagreb. Samples were collected from three markets, three retail chains, and three organic product stores. French bean were dried at 105 °C, subsequently ground, and homogenized. Nitrogen was determined using a modified Kjeldahl method, while after digestion with concentrated HNO3 and HClO4 in a microwave oven, phosphorus was determined using a spectrophotometer, potassium by flame photometry, and calcium and magnesium by atomic absorption spectrometry. Dry matter (DM) in French bean samples ranged from 8.18 to 10.38%. The determined amounts of macroelements in the dry matter of the beans were as follows: 3.71% N DM, 0.45-0.47% P DM, 2.19-2.87% K DM, 0.29-0.34% Mg DM, and 0.37-0.7% Ca DM. Values in fresh matter were: 307.84-379.04 mg N/100 g fresh matter, 37.97-47.94 mg P/100 g fresh matter, 197.81-225.79 mg K/100 g fresh matter, 27.59-32.69 mg Mg/100 g fresh matter, and 36.97-66.42 mg Ca/100 g fresh matter. |