TY  - JOUR
U1  - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed)
A1  - Joeres, Eike
A1  - Schölzel, Henry
A1  - Drusch, Stephan
A1  - Töpfl, Stefan
A1  - Heinz, Volker
A1  - Terjung, Nino
T1  - Ohmic vs. conventional heating : Influence of moderate electric fields on properties of egg white protein gels
JF  - Food Hydrocolloids
N2  - The present study investigates properties of heat-induced, self-standing gels of globular proteins. Native egg white protein (EWP) with 9,8 wt% protein and 0,395 wt% NaCl content was adjusted to pH = 7,0 and heated from 25 to 85 °C via Ohmic heating (OH) and conventional heating (COV) with respective come-up times (CUT, 240 and 1200 s) and holding times (HOLD, 30 and 900 s). Gels heated under OH showed lower denaturation levels and less water holding capacity. When HOLD was short, the firmness of OH gels exceeded COV gel firmness but deceeded at long HOLD. Similarly, at short HOLD OH samples presented higher hydrophobic interactions whereas at long HOLD COV gels showed more hydrophobic interactions. This correlated with changes of intermolecular beta-sheet structures which increased with HOLD at COV but decreased or remained unchanged during OH. Furthermore, as an SDS-PAGE revealed the main EWP, ovalbumin, did not fully denature when heated via OH, this lead to the assumption that the oscillatory electric field partially interferes the complete denaturation and development of intermolecular beta-sheet structures and hydrophobic interactions during thermal gelation of this protein. Scanning electron microscopy also showed deviances in network structures between OH and COV as COV gels exhibited a denser and OH gels a more open and porous network structure.
KW  - Ohmic heating
KW  - Thermal denaturation
KW  - Secondary protein structure
KW  - Hydrophobic interactions
KW  - Ovalbumin
KW  - Intermolecular beta-sheet structures
Y1  - 2022
SN  - 1873-7137
SS  - 1873-7137
SN  - 0268-005X
SS  - 0268-005X
U6  - https://doi.org/10.1016/j.foodhyd.2022.107519
DO  - https://doi.org/10.1016/j.foodhyd.2022.107519
N1  - Zugriff im Hochschulnetz
IS  - 127
SP  - 11
S1  - 11
ER  -