Microstructure of Frankfurters Extended with Wheat Germ Proteins

Transmission electron microscopy was utilized to study the microsctructure of frankfurters extended with wheat germ protein flour (WGPF) at 3.5, 5.0, and 7.0%. Samples with 3.5% WGPF showed a denser matrix than the control. They also had a uniform interfacial protein film (IPF) with a slight increase in average thickness. At WGPF >3.5%, no further effects on IPF were observed. At 7.0% WGPF, an increase in added water, and the resultant dilution of meat and fat components, resulted in fewer fat globules, some with incomplete IPFs. Proteins in the WGPF contributed to IPF formation up to a specific level. Nonprotein components also were important in batter stability by absorbing water.