Sublethal moderated pressure pre-treatments for subsequent shorter and improved egg white thermal pasteurization

Abstract

The possibility of using a sublethal moderate pressure11 Moderate pressure (MP).(MP) pre-treatment followed by a shorter and so gentler thermal pasteurization22 Thermal Pasteurization (TP). (TP), (MP-TP), was assessed, as an alternative to commercial egg white33 Egg White (EW). (EW) TP, by evaluating the lethal efficacy against Salmonella Senftenberg and influence on the functional and physicochemical properties of EW. MP-TP treatments applied at pressures ≥ 90 MPa resulted in a synergistic lethal effect, thus reducing the thermal resistance of S. Senftenberg, leading to at least 4.4 log10 cycles inactivation. In addition, a similar reduction was obtained for L. innocua using MP-TP. EW processed by MP-TP was less viscous (44%), showed better foaming capacity (119%), and produced harder (9–21%) and stiffer (17%) heat-induced gels than commercial TP samples. For the latter (TP samples), a higher increase in turbidity and soluble protein loss (about 35%), suggests higher protein aggregation than in MP-TP EW. Additionally, the volatile profile of EW was affected by all the treatments, with the greatest impact being caused by commercial TP, which had highest content of hydrocarbons compounds, butyl acetate, esters and eucalyptol. Meringues prepared with EW treated by MP-TP and commercial TP had similar global acceptability. Overall, shorter (and so gentler) TP for MP-TP samples resulted in better retention of EW properties than commercial TP.

Keywords

• Egg white
• Moderate pressure
• Thermal pasteurization
• Salmonella Senftenberg
• Physicochemical/functional properties