Journal
FOOD HYDROCOLLOIDS
Volume 23, Issue 7, Pages 1864-1876Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.foodhyd.2009.03.003
Keywords
Foam; Sodium caseinate; Whey protein concentrate; Protein adsorption; pH dependence
Categories
Funding
- Kraft Foods, Glenview, IL
Ask authors/readers for more resources
We explored the foaming behavior of the two main types of milk proteins: flexible caseins and globular whey proteins. Direct foam comparison was complemented with measurements in model experiments such as thin foam films, dynamic surface tension, and protein adsorption. Foaming was studied as a function of pH (from below to above isoelectric point, pI) and range of ionic strengths. Maximum foamability was observed near pI approximate to 4.2 for WPC in contrast to sodium caseinate which had minimum foaming near pI = 4.6. Good foamability behavior correlated well with an increased adsorption, faster dynamic surface tension decrease and increased film lifetime. Differences in the stability of the foams and foam were explained with the different molecular structure and different aggregation behavior of the two protein types. Far from its isoelectric pI, casein adsorption layers are denser and thicker thus ensuring better stabilization. Added electrolyte increased further the adsorption and the repulsion between the surfaces (probably by steric and/or osmotic mechanism). In contrast the globular molecules of WPC probably could not compact well to ensure the necessary films and foams stabilization far from pI, even after electrolyte addition. (C) 2009 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available