High pressure effect on foaming behaviour of whey protein isolate

Citation
E. Ibanoglu et S. Karatas, High pressure effect on foaming behaviour of whey protein isolate, J FOOD ENG, 47(1), 2001, pp. 31-36
Citations number
29
Categorie Soggetti
Food Science/Nutrition
Journal title
JOURNAL OF FOOD ENGINEERING
ISSN journal
02608774 → ACNP
Volume
47
Issue
1
Year of publication
2001
Pages
31 - 36
Database
ISI
SICI code
0260-8774(200101)47:1<31:HPEOFB>2.0.ZU;2-J
Abstract
The effect of pressure-processing at 150-450 MPa for 5-25 mm on foaming beh aviour of whey protein isolate (WPI) have been investigated in pH range of 5.0-7.0. Assessment of foaming properties has been based on the total foam volume (FV) produced and the foam stability (FS), and the rime for loss of half the initial FV. Response surface methodology has been applied to find the regression equations for predicting the FV and FS in terms of independe nt variables (the intensity of pressure, the treatment time and the pH). Pr otein solutions (1% w/v, 50 mM phosphate buffer) were pressure-processed an d foams were produced from dilute solutions of WPI (0.005% w/v) by sparging with nitrogen gas at constant flow rate (0.2 +/- 0.01 dm(3)/min) and const ant temperature (20 degrees C). It has been found that pH is significant (P less than or equal to 0.01) on both FV and FS; FV is influenced significan tly (P less than or equal to 0.05) by pressure-intensity whereas the effect of pressure-treatment time on either FV or FS is not significant (P less t han or equal to 0.05). Foaming properties of WPI were reduced as the pH app roached to the isoelectric point of proteins due to enhanced aggregation. P ressurisation at high-protein concentration (2% w/v) or in high-buffer mola rity (100 mM) has been observed to diminish the foaming properties of WPI. (C) 2000 Elsevier Science Ltd. All rights reserved.