Re‐examination of the interactions between starch and salts of metals from the non‐transition groups

Abstract

The interactions between potato starch and the salts of alkali–earth metals and lead were examined by using scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), differential scanning calorimetry (DSC), 17O and 35Cl NMR. For the starch blended with saturated solutions of the salts, gel‐like, shear‐thinning or semi‐solid appearances were observed in relation to the ion property of the salts. The volume of saturated salt solutions required for producing shear‐thinning properties correlated significantly with the property of anions. SEM and EDS studies on the starches after soaking in 0.5 M salt solutions suggest that both divalent cations and accompanying anions of the salts penetrated into the granule during soaking treatments. Also, the cations (especially Mg2+ and Pb2+) and anions both displayed some influence on the onset (To) and peak (Tp) temperatures as well as the enthalpy change (ΔH) during thermolysis of the starches. From these results and NMR data, the major ion species (anions or cations) interacting directly with starch could be elucidated partially with respect to the salt variety and concentration and preparation condition. The roles of free water content and water structure in the physical characteristics of the starch systems examined were negligible.

New insights on the characteristics of starch network

“…The ability of calcium lactate in increasing the phase transition temperature, both in the presence and absence of glycerol, may be due to Ca 2+ -cross-linking that stabilizing the ordered structure of starch fraction in the granules (Lai, Tomasik, Yen, Hung, & Lii, 2001). Nonetheless, the presence of calcium lactate and cysteine mixture drastically lowered the gelatinization enthalpy of the 40% MBS slurries.…”

Study of quantitative interactions of potato and corn starch granules with ions in diluted solutions of heavy metal salts

“…CuCl + , present in copper chloride solution (Neilson et al, 1995;Powell et al, 2007). Migration of some Cl -ions into the granule inside should be also possible because of weak repulsion of these ions by the granule surface (Oosten, 1990) and their direct interactions with hydrogen atoms of starch hydroxyl groups suggested in the literature (Lai et al, 2001;Kunz, 2010). In addition, the granules became less negative in slightly acidic CuCl 2 solution (pH=4.9), because of the cation hydrolysis, what could promote migration of Clinto the granule interior.…”

“…Use of salts in food production affects a quality of obtained starch products (Bunger, Moyano & Rioseco, 2003). It has been demonstrated that starch granules soaked in salt solutions retain cations of alkali and transition metals (Lai, Tomasik , Yen , Hung & Lii, 2001;Ciesielski, Lii, Yen & Tomasik, 2003;Śmigielska, Lewandowicz, Goślar & Hoffmann, 2004Szymońska, Wieczorek, Molenda & Bielańska, 2008;Szczygieł et al, 2014). The hydroxyl groups of α-D-glucose units of starch granules are the possible places of interaction of metal ions with polysaccharide chains (Oosten, 1990;Ciesielski & Tomasik, 2004b).…”

Corn starch systems as carriers for yerba mate (Ilex paraguariensis) antioxidants: Effect of mineral addition

“…Extensive studies of the interaction of metal ions with various types of native and modified starches have shown that ions bind to functional groups of starch in different ways (Ciesielski et al, 2003;Łabanowska et al, 2013;Lai et al, 2001). For the alkali-earth metal ions, it is postulated that they can form complexes with starch, but also as for alkali metal ions, there are electrostatic interactions between the cations and anions interacting with OH groups.…”