Texture-Structure Relationships in Textured Soy Protein. V. Influence of pH and Protein Acylation on Extrusion Texturization

Role of carbohydrates in soya extrusion

“…This conclusion refutes the idea-proposed initially by Burgess & Stanley (1976) and more recently by Simonsky & Stanley (1982)-that intermolecular peptide bonds are involved in the stabilization of extruded soy protein. Because ninhydrin resulted in a product lacking in alveolate morphology, these authors proposed that ninhydrin was successful in competing with potential peptide forming groups.…”

“…Solubility work directed at identifying the bonding forces responsible for the characteristic texture and microstructue of soya extrudates has given rise to widely varying conclusions. While some workers (Rhee, Kuo & Lusas, 1981;Jeuninck & Cheftel, 1979) have reported almost 100% solubility in a solvent containing 1 % sodium dodecyl sulphate (SDS) and 1% 2-mercaptoethanol (ME), a solvent mixture in which all stabilizing forces except non-disulphide covalent bonds are broken, others (Burgess & Stanley, 1976;Simonsky & Stanley, 1982) have reported urea, SDS and ME to be largely ineffective in disrupting the bonding forces in texturized soya. These workers claim that isopeptide bonds are of importance.…”

New protein preparations from soy flour obtained by limited enzymic hydrolysis of extrudates

“…Its magnitude depends, among others, on the kind of hydrolysed protein. Since the raw material for hydrolysis (ExSF) was previously subjected to extrusion, it may be assumed that its structure, consisting of denatured protein, is stabilised-besides hydrogen bonds, electrostatic and hydrophobic interactions-also by disulfide and other covalent bonds (Simonsky & Stanley, 1982;Ledward & Mitchell, 1988;Prudencio-Ferreira & Areas, 1993). As shown by Marsman, Gruppen, Mul and Voragen (1997), such soy protein, denatured as a result of extrusion, easily undergoes an enzymic hydrolysis.…”

Lipid Composition and Hydration Characteristics of Lung Protein Isolates Defatted by Several Solvents

“…Several texturization (restructuring) techniques were investigated but thermoplastic extrusion is the most applicable due to its low cost and simplicity (Kinsella, 1978;Mittal and Lawrie, 1984). In spite of the rapid development of extrusion technology (Zeuthen et al, 1984), understanding of the molecular mechanisms of protein texturization by extrusion is still limited and controversial (Baird, 1982;Burgess and Stanley, 1976;Simonsky and Stanley, 1982;Smith et al, 1982).…”