[2Jp01-11] 資源循環、嚥下、咀嚼機能、食品物性

5:15 PM - 5:30 PM JST(8:15 AM - 8:30 AM UTC)

[2Jp10] Clarification of changes in ovalbumin foam properties by tannic acid

*Tetsuo Torisu¹, Junya Mizuguchi¹, Ryosuke Tanoue¹, Susumu Uchiyama¹, Hiromi Miki², Norifumi Yamada² (1. Graduate School of Engineering, The University of Osaka, 2. Institute of Materials Structure Science, High Energy Accelerator Research Organization)

Keywords:

Protein,Foam,Mass spectrometry,egg

[Purpose] Foam gives food a unique texture and flavor. Although the foam stabilizing effect of food proteins has attracted attention, the stabilizing effect is often insufficient for industrial purposes. Therefore, the development of protein processing or additives to enhance the stabilizing effect is expected. In this study, we aimed to evaluate the changes in foam properties of egg white albumin (OVA) solution by the addition of tannic acid and to elucidate the molecular mechanism of the changes. [Methods] Tannic acid was added to OVA at various concentrations, and foaming properties were evaluated. The physical properties of the OVA solutions and the interaction between OVA and tannic acid were also evaluated. In addition, hydrogen/deuterium exchange mass spectrometry (HDX-MS) was employed to obtain structural insights of OVA at the air-water interface. Neutron reflectometry was also used to measure the thickness of the adsorbed layer at the air-water interface. [Results] The foaming ability of the OVA solution was decreased, whereas the foaming stability was improved by the addition of tannic acid. Fluorescence measurements indicated that tannic acid could bind to the hydrophobic region of OVA. The interaction could decrease the diffusion rate and increase the viscosity, contributing to a decrease in the adsorption rate of OVA to the air-water interface and a decrease in the drainage rate, leading to a decrease in foaming ability and an increase in foaming stability. HDX-MS revealed that the addition of tannic acid changed the orientation of OVA at the air-water interface. The change in the orientation of OVA was supported by neutron reflectometry, which showed that the thicker layer can be formed in the presence of tannic acid.