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Disulfide‐mediated Polymerization Reactions and Physical Properties of Heated WPI‐stabilized Emulsions
Author(s) -
MONAHAN F.J.,
McCLEMENTS D.J.,
GERMAN J.B.
Publication year - 1996
Publication title -
journal of food science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.772
H-Index - 150
eISSN - 1750-3841
pISSN - 0022-1147
DOI - 10.1111/j.1365-2621.1996.tb13143.x
Subject(s) - creaming , chemistry , emulsion , viscosity , whey protein isolate , disulfide bond , polymerization , oil droplet , protein aggregation , whey protein , adsorption , chemical engineering , biophysics , chromatography , organic chemistry , biochemistry , polymer , materials science , engineering , composite material , biology
Heating a 19 wt% corn oil‐in‐water emulsion stabilized by 1 wt% whey protein isolate from 30 to 70°C and then cooling to 25°C for at least 15 hr, brought about minimal changes in droplet aggregation, apparent viscosity and susceptibility to creaming. At 75°C, droplet aggregation occurred but this decreased on heating to 90°C. The apparent viscosity and susceptibility of droplets to creaming increased as the degree of droplet aggregation increased. Inclusion of the sulfhydryl blocking agent N‐ethylmaleimide to inhibit thiol/disulfide interchange reactions did not affect droplet aggregation but resulted in higher apparent viscosity values and susceptibility to creaming at 85 and 90°C and not at lower temperatures. The results suggest that droplet aggregation results from noncovalent interactions between unfolded protein molecules adsorbed on different droplets and that the interactions are strengthened by disulfide bonds.