Influence of pressure pre-treatments on liquid whole egg thermal pasteurization – microbiological, physicochemical and functional properties

Abstract

As a possible alternative to commercial thermal pasteurization1 (TP, 60 ºC/3.5 min) of liquid whole egg2 (LWE), a pasteurization based on the application of pressure pre-treatments (50 – 250 MPa/5 min) before a shorter TP (60 ºC/1.75 min) was investigated. These combined treatments inactivated 3.35 to at least 6.09 log10 cycles of S. Senftenberg 775/W, achieving comparable to greater inactivation as commercial TP (at pressures ≥ 200 MPa).

The treated samples presented lower soluble protein and emulsifying activity than non-treated LWE, yet higher viscosity and improved foaming capacity. In contrast to commercial TP, the LWE treated by moderate pressure3 (MP) before a shorter TP (MP-TP) showed higher soluble protein (7 %) and viscosity (49 %), better emulsifying properties (27 – 67 %), and lower total carotenoids content (9 %). Concerning sensory analysis, egg tarts prepared with non-treated and treated LWE obtained similar sensory acceptability.

Therefore, the heat sensitization effect induced by pressure pre-treatments on the S. Senftenberg 775/W population allows the reduction of TP time, a lethality effect equivalent to commercial TP and similar or improved functionality, being a very promising alternative to produce safe and better functional quality LWE.