Conversion of ovalbumin to S-ovalbumin during egg storage impacts pound cake properties

During egg storage, the main egg white protein ovalbumin is converted to S-ovalbumin. The denaturation temperature of S-ovalbumin is 92.5 °C, that of ovalbumin is 84.5 °C. Correlations between egg freshness on cake volume and texture have been investigated in literature. However, the specific role of S-ovalbumin on pound cake batter and product crumb properties is not clear. We here investigated the impact of S-ovalbumin on pound cake baking and on cake quality. To obtain egg white with different levels of S-ovalbumin, fresh eggs were stored for 28 days at 6 °C and at 23 °C. Batters were made with different combinations of egg white from fresh and stored eggs and egg yolk. Batter viscosity and enthalpy changes during heating were evaluated with the Rapid Visco Analyser (RVA) and Differential Scanning Calorimetry (DSC), respectively. Volume and texture of the resulting pound cakes were determined. Both DSC profiles and RVA viscosity profiles of the batters were significantly impacted by the level of S-ovalbumin which was higher after storage at 23 °C. With higher levels of S-ovalbumin, egg denaturation in the batter takes place at higher temperatures ( from 86 °C to 90 °C in excess of water) and the viscosity at the end of the RVA profile was lower (from 21 Pa.s to 14 Pa.s). Cake volume and crumb hardness were not impacted by the S-ovalbumin level but cakes baked with egg white enriched in S-ovalbumin had a lower crumb springiness (from 86% to 83%) and cohesiveness (from 65% to 61%). This indicates that S-ovalbumin impacts both batter viscosity during baking and crumb springiness and cohesiveness after baking.status: publishe