Effects of Fucoidan, an Anionic Sulfated Polysaccharide, on the Foam Properties of Ovalbumin

Abstract

Foamability has deep relationships with microstructure of the inner of substance, size of bubble and interfacial tension. Thus, these characteristics of foamability have been used worldwide for food such as beer, bread, ice cream marshmallow, meringue and mousse. Food polymers such as protein and polysaccharide form the viscoelastic film on the surface of air bubble which can lead the change of surface tension. When surface tension gets higher and higher, the surface energy increase continually as well. This phenomenon occurs when a liquid changes to a gas. In this experiment, we measured the stability of air bubble and the condensation process by foam stability tester with different conductivity as far as the state of charge is concerned. Moreover, we also used the Du Nuoy Ring Tensiometer K100 to measure the surface tension of bubble. As a result, surface tension was decreased effectively, from 51.08 mN/m, only ovalbumin, to 44.72 mN/m when fucoidan was added at pH 5. Besides, we compared the foamability and foam stability between only ovalbumin and fucoidan added ovalbumin foam. The half-life of foam was increased from 212 second, only ovalbumin, to 370 second, when fucoidan was added, at pH 4. At pH5, to 621 second from 543 second, 78 second was improved. The results show that the foams added with fucoidan has much better stability than the control sample. The foam with fucoidan sample has better stability and low interfacial tension. Apparently, fucoidan plays a key role for stability. These properties of fucoidan can be used for various applications in the food industry.