title: Molecular and Supermolecular Structure of Commercial Pyrodextrins.
abstract: Size exclusion chromatography with triple detection as well as infrared spectroscopy studies of commercially available pyrodextrins proved that these molecules are characterized not only by significantly lower molecular mass, in comparison to that of native starch, but also by increased branching. Therefore, pyrodextrins adopt a very compact structure in solution and show Newtonian behavior under shear in spite of their molecular masses of tens of thousands Daltons. The results also indicate that 50% reduction of digestibility of pyrodextrins is, to a minor extent, caused by formation of low-molecular color compounds containing carbonyl functional groups. The main reason is, as postulated in the literature, transglycosidation that leads to decreased occurrence of α-1,4-glycoside bonds in the molecular structure. In the process of dextrinization starch also undergoes changes in supermolecular structure, which, however, have no influence on digestibility. Likewise, the effect of formation of low-molecular colorful compounds containing carbonyl groups is not crucial.
authors.affiliation: Dept. of Food Concentrates and Starch Products, Prof Wacław Dąbrowski Inst. of Agricultural and Food Biotechnology, Poznań, Poland. lethanh@man.poznan.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Le Thanh-Blicharz
authors.affiliation: Inst. of Animal Reproduction and Food Research of Polish Academy of Sciences, Olsztyn, Poland.
authors.forename: Wioletta
authors.initials: W
authors.lastname: Błaszczak
authors.affiliation: Inst. of Food Technology of Plant Origin, Poznań Univ. of Life Sciences, Poznań, Poland.
authors.forename: Artur
authors.initials: A
authors.lastname: Szwengiel
authors.affiliation: Inst. of Chemical Technology and Engineering, Poznań Univ. of Technology, Poznań, Poland.
authors.forename: Dominik
authors.initials: D
authors.lastname: Paukszta
authors.affiliation: with Dept. of Biotechnology and Food Microbiology, Poznań Univ. of Life Sciences, Poznań, Poland.
authors.forename: Grażyna
authors.initials: G
authors.lastname: Lewandowicz
mesh_terms: D002850:Chromatography, Gel; D003912:Dextrins / Q000737:chemistry*; D015394:Molecular Structure; D008970:Molecular Weight; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D003912:Dextrins
keywords: IR spectroscopy; gyration and hydrodynamic radius; molecular mass distribution; pyrodextrins; structure