"b-Conglycin and glycinin soybean proteins emulsions trated by a combined temperature-high pressure process"

PUPPO, M.C; BEAUMAL, V; SPERONI, F; DE LAMBALLERIE, M; AÑON, M.C; ANTON, M

FOOD HYDROCOLLOIDS

ELSEVIER SCI LTD

Año: 2011 vol. 25 p. 389 - 397

0268-005X

Most studies on functionality of soybean proteins have been made with total protein isolates, with the drawback to limit the knowledge of phenomena due to the important complexity of protein composition. In this study we have tried to better understand the behavior of soy emulsions by using their two partially purified fractions: b-conglycinin (7S) and glycinin (11S). Furthermore, we have assessed the combined effect of temperature (20e60 C) and high pressure (0.1e600 MPa) on physicochemical, microstructural and rheological properties of oil-in-water emulsions prepared with 7S or 11S proteins at 7% (w/v). Our results show that 7S and 11S emulsions behaved differently under the combined treatments and that 7S protein was responsible for the global properties of soybean emulsions, whereas 11S proteins exerted a negligible effect. From 400 MPa and at 60 C, we have noticed for 7S emulsions an increase of flocculation and gelation, largely confirmed by confocal microscopy due to aggregation between adsorbed and aqueous 7S proteins. Globallywehave evidenced that temperature reinforces the effect of high pressure and that the threshold to obtain some changes is 400 MPa. The very different behavior of 7S and 11S proteins in emulsions under treatments could help to orientate their commercial use as function of planed treatments.© 2011 Elsevier Ltd. All rights reserved