Protein–lipid interactions in gluten elucidated using acetic acid fractionation

Gliadins in Foods and the Electronic Tongue

“…A more detailed analysis of the results, shown in Table 18.2, indicate that apparently the type of additive has less influence in the potentiometric signal responses than the type of plasticizer. Indeed, two plasticizers [tris(2-ethylhexyl) phosphate and dioctyl phenylphosphonate] gave the best correlations, which was expected due to the presence of the phosphate group that enhances the gliadin-lipid interaction (McCann et al, 2009).…”

“…Furthermore, it is accepted that lipids interact with proteins during gluten formation; thus, lipids could enhance the formation of large complex aggregates involving both gliadin and glutenin proteins (Carcea and Schofield, 1996). Besides, it is known that nonpolar lipids can be associated with glutenins through either hydrophobic interactions or hydrogen bonds, whereas polar lipids containing phosphate groups preferentially interact with gliadin (McCann et al, 2009). Moreover, when lipid/ polymer membranes are applied for protein detection, namely gliadin, that does not bind directly, it is expected that their behavior could mimic that of protein-lipid interactions occurring in biological membranes, where unspecific hydrophobic association or electrostatic interactions between protein and lipid head groups occur (Thomas and Glomset, 1999;Zhao and Lappalainen, 2012).…”

“…This result suggests that, in principle, the lipidic membranes are responding preferentially to gliadin over glutenin proteins. This apparent preference may be tentatively explained taking into account that: (1) glutenin has a greater average molecular weight (70-90 kDa) compared to gliadin (30-50 kDa) (Wieser, 2008), which may favor the gliadin possible adsorption over glutenin and (2) lipidic membranes used preferentially interact with gliadin over glutenin proteins due to their polarity and presence of a phosphate group in some of them (McCann et al, 2009). A more detailed analysis of the results, shown in Table 18.2, indicate that apparently the type of additive has less influence in the potentiometric signal responses than the type of plasticizer.…”

Solvent effects on the molecular structures of crude gliadins as revealed by density and ultrasound velocity measurements

“…One reason might be that crude gliadins in 4 mM HAc have more charged hydrations because the net charges of the protein molecules are increased in dilute acid (Damodaran, 1996). Crude gliadins in 70% (v/v) EtOH might interact mainly with ethanol molecules through hydrophobic interactions (Damodaran, 1996;McCann et al, 2009 (Kharakoz, 1991;Taulier and Chalikian, 2002). However, this reason is not strong enough to explain the remarkable difference between the compressible properties of crude gliadins in 4 mM HAc and 70% (v/v) EtOH.…”

“…Complexes formed by gliadins and ethanol soluble LMW-glutenins and lipids were found in aqueous alcoholic extracts of wheat flours (Békés et al, 1983a;Békés et al, 1983b;Zawistowska et al, 1984;McCann et al, 2009) and were reported to have positive effects on flour breadmaking suitability (Békés et al, 1992).…”