Heat Curing of Soy Protein Films at Selected Temperatures and Pressures

Mechanism of microwave-accelerated soy protein isolate–saccharide graft reactions

“…These findings most likely represent a blue shift (towards shorter wavelength) or a red shift (towards longer wavelength) in the absorbance spectrum of the tryptophan buried within the hydrophobic core of the protein, possibly due to movement of an aromatic residue of tryptophan into a more hydrophilic (blue shift) or a more hydrophobic (red shift) environment (Andrews & Forster, 1972), and thus imply that MH can induce protein unfolding, in agreement with previous findings (Bohr & Bohr, 2000;George, Bilek, & McKenzie, 2008), while WH may lead to secondary aggregation (Kim et al, 2002) and induce protein folding. As the time of MH/WH to rise, there was an increase/decrease in the solvent (water) exposure of the hydrophobic core residues, thus causing rise/decline in UV absorbance spectrum accordingly.…”

“…Moreover, lactose has stronger reduction than SS, so free sulfhydryl groups produced by disulfide bonds in SPI-lactose reactants rose more rapidly than those in SPI-SS or SPI systems in the early stage of MH. On the other hand, WH or conventional heating methods do not favour the reduction of disulfide bonds, but can improve the crosslinking of free sulfhydryl groups (Kim, Weller, Hanna, & Gennadios, 2002). And the increase of free SH contents in the early stage of MH and the decrease of DS contents during MH are similar to the findings of protein-saccharide graft reaction in the dry state reported by Handa and Kuroda (1999).…”

Preparation and characterization of proteinous film from lentil (Lens culinaris)

“…It can be resulted from slight heat denaturation of LPC films during formation (70°C, 20 min) and a little more glycerol content. There are evidences that the intensity of heat treatments of proteins at alkaline pH has a significant effect on physical properties of films because it promoted formation of intra-and inter-molecular cross-links (Kim, Weller, Hanna, & Gennadios, 2002). Heating soy protein solution at 80 or 90°C for various periods of time has led to form films with increased TS, darker color and lowered E and WVP values (Gennadios, Ghorpade, Weller, & Hanna, 1996).…”

Modulation of mechanical and surface hydrophobic properties of food protein films by transglutaminase treatment

“…Lots of treatments, including physical, chemical and even enzymatic methods, have been tried to improve the mechanical properties of protein-based edible films, including the addition of chemical cross-linking agents (e.g., aldehydes), heat curing, the transglutaminase-induced crosslinking treatment, ultraviolet or c-irradiation treatment (de Carvalho & Grosso, 2004;Hernández-Muñ oz, Villalobos, & Chiralt, 2004;Kim, Weller, Hanna, & Gennadios, 2002;Larré, Desserme, Barbot, & Gueguen, 2000;Liu, Tellez-Garay, & Castell-Perez, 2004;Mariniello et al, 2003;Rhim, Gennadios, Fu, Weller, & Hanna, 1999;Tang, Jiang, Wen, & Yang, 2005;Vachon et al, 2000). Of these treatments, the enzymatic treatment by means of transglutaminase seems to be most potential for improving the mechanical properties of protein films, due to the consideration from safety and effectiveness.…”