Effect of microwave radiation on physico-chemical properties and structure of cereal starches

Functional Properties of Some Non-Conventional Treated Starches

“…Microwave treatment on starch were carried out especially on samples with high water content, over 20%, and less on samples with low (1 -5%) or limited (7 -15%) moisture content. The results showed that microwaves may determine the rearrangement of intermolecular structure indicating that the starch granule structure is disintegrated and, consequently, they lead to slight reduction of the water absorption ability, of solubility and swelling power as well as changes of the gelatinization temperature, syneresis or paste viscosity (Lewandowicz et al, 1997;Lewandowicz et al, 2000;Gonzalez & Perez, 2002;Gonzalez Parada & Perez Sira, 2003;Szepes et al, 2005;Luo et al, 2006;Lares & Perez, 2006) strongly correlated with experimental treatment parameters. Starch exposed to electrical discharges (plasma) may suffer either crosslinking phenomenon (Zou et al, 2004 or depolymerization to dextrins with different molecular weights (Lii et al, 2002a;Lii et al, 2002b) …”

Microwave absorption capacity of rice flour. Impact of the radiation on rice flour microstructure, thermal and viscometric properties

“…Therefore, the increase of gelatinization temperature observed in moistened treated flours would be in agreement with XRD results. The rise in gelatinization temperatures has also been associated with the formation of amyloseamylose and amylose-lipid complexes within the starch granule and an association and a more stable configuration in the granular structure (Lewandowicz et al 2000). A slight but significant decrease in the gelatinization enthalpy of the microwaved-treated flours was observed probably because the samples underwent a partial gelatinization as a consequence of microwave treatment.…”

Effect of Phosphorylation and Copper(II) or Iron(II) Ions Enrichment on Some Physicochemical Properties of Spelt Starch

“…However, phosphorylation considerably lowered the pasting temperature, and copper-enriched spelt monostarch phosphate had the lowest pasting temperature of all the starches investigated (Table 3). A change of certain pasting properties of examined starches, including pasting temperature (Table 3) may be affected by changes in the crystal structure during process of starch modification as Lewandowicz et al (2000) reported for wheat and corn starches. Copper(II) enrichment resulted in increased values of peak viscosity (PV), trough (TV), final viscosity (FV) and setback (SB) compared with the natural starch; this was in contrast to the corresponding values obtained following iron(II) enrichment, which were lower than those for natural starch (Table 3).…”