title: Study of quantitative interactions of potato and corn starch granules with ions in diluted solutions of heavy metal salts.
abstract: Interactions of potato and corn starch granules with ions in diluted solutions of silver, lead, copper or iron salts were investigated. It was shown experimentally that granules accumulated the cations in amounts depending on the granule structure and water content as well as a type of both metal and counter-ions present in solution. Potato starch retained almost three times more cations compared to corn starch what was proportional to the total phosphorous content in these starches. Quantity of milligrams of cations bound by 1g of starch was inversely correlated with the cation hydration. Ag(+), Pb(2+) and Cu(2+) were connected in stoichiometric amounts of moles to semicrystalline and amorphous parts of the granules. Fe(3+) ions were accumulated in higher than stoichiometric quantities mainly in granule amorphous regions. Metal ions penetrated into granules together with anions except nitrates which remained on surface of potato starch granules. Cations facilitated the starch thermal decomposition in accordance with values of their standard redox potentials. Nitrates supported this process only in the presence of base metal cations.
authors.affiliation: Department of Chemistry and Physics, Agricultural University, 122, Balicka Str., 30-149 Krakow, Poland. Electronic address: joanna.szymonska@ur.krakow.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Szymońska
authors.affiliation: Faculty of Chemistry, Jagiellonian University, 3, Ingardena Str., 30-060 Krakow, Poland. Electronic address: molendam@chemia.uj.edu.pl.
authors.forename: Marcin
authors.initials: M
authors.lastname: Molenda
authors.affiliation: Department of Agricultural Chemistry, Agricultural University, 21, Mickiewicza Ave., 30-120 Krakow, Poland. Electronic address: rrwieczo@cyf-kr.edu.pl.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Wieczorek
mesh_terms: D000838:Anions / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D019216:Metals, Heavy / Q000737:chemistry* / Q000302:isolation & purification; D009566:Nitrates / Q000737:chemistry; D010084:Oxidation-Reduction; D010758:Phosphorus / Q000737:chemistry; D012492:Salts / Q000737:chemistry* / Q000302:isolation & purification; D011198:Solanum tuberosum / Q000737:chemistry*; D012996:Solutions; D013213:Starch / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000838:Anions; D002412:Cations; D019216:Metals, Heavy; D009566:Nitrates; D012492:Salts; D012996:Solutions; D014867:Water; D010758:Phosphorus; D013213:Starch
keywords: Bioelements in foods; Ion distribution in starch; Metal ion biosorption; Starch oxidation