Statistical analysis of effects of industrial processing steps on functional properties of pasteurised liquid egg white

Abstract

Egg white is widely used as an ingredient in the food industry owing to its excellent functional properties. The transformation of shell eggs into safe liquid, frozen, or spray-dried egg white with extended shelf life requires many technological operations that result in modifications to the egg white's functional properties. The present study highlights the critical steps affecting foaming and gelling properties during a classical pasteurised liquid egg white process. The main source of variation in functional properties was raw material quality, accounting for 70% of the variability. Part of the remaining 30% was explained by mechanical egg white-yolk separation, tank storage, pasteurisation and homogenisation that resulted in damage to the functional properties, whereas initial flow through pipes and pumping resulted in their improvement. The effects of these steps could be grouped according to the type of treatment undertaken. Dry matter content, pH and treatment intensity at each step contributed about 30% of the variability in functional properties due to processing steps. Relationships between the modifications of egg white functional properties and protein conformation were established. Between 46 and 78% of the variability in functional properties can be explained by protein denaturation, temperature and enthalpy changes.

Egg white drying: Influence of industrial processing steps on protein structure and functionalities

“…However, they are very similar to those we observed in a previous study (Lechevalier, Périnel, et al, 2005). In that case, the differences between the trials were attributed to the different origins of the eggs and also to different storage lengths, in agreement with the literature Hammershoj, Larsen, Andersen, & Qvist, 2002;Kreuzer, Jaenecke, & Flock, 1995).…”

“…Foam density was calculated from the mass of a given volume of foam, and foam stability as the percentage of liquid held in foam after 1 h, as suggested by Lechevalier, Périnel, et al (2005).…”

Functional properties of pasteurised liquid whole egg products as affected by the hygienic quality of the raw eggs

“…Actually, many factors have been identified as sources of variation for these functional properties (Rossi, 1999). Some of them are related to the quality of the raw material in terms of egg freshness and composition (Donovan, 1977;Hammershoj, Larsen, Andersen, & Qvist, 2002;Jones, 2007;Meehan, Sugihara, & Kline, 1962;Rossi, Fessas, & Pompei, 2001), others are linked to processing treatments such as homogenisation, pasteurisation and freezing (Allais, Edoura-Gaena, Gros, & Trystram, 2006;Dawson, 1996;Garibaldi, Donovan, Davis, & Cimino, 1968;Guilmineau & Kulozik, 2007;Hamid-Samimi & Swartzel, 1984;Jaekel, Dautel, & Ternes, 2008;Lechevalier et al, 2005;Rossi, Pompei, & Casiraghi, 1997;Yang & Cotteril, 1989). Studying the industrial processing of pasteurised liquid egg white, Lechevalier et al (2005) tried to quantify the influence of the different factors on functional properties, concluding that the quality of the raw material is the main source of variation, accounting for 70% of variability.…”

Scientific Opinion on the public health risks of table eggs due to deterioration and development of pathogens

“…The better the membrane resistance, the better the separation between egg white and egg yolk. Even present as trace levels (0.1 to 0.2 %), egg yolk strongly decreases the foaming capacity of egg white (St. John and Flor, 1930;Lechevalier et al, 2005). The addition of 5 to 20 % egg white in egg yolk also leads to a decrease in egg yolk viscosity in the range of 6-90 % (Li-Chan et al, 1995).The resistance of the vitelline membrane is decreased when eggs are submitted to vibrations during transport and storage, and especially at high temperature (Berardinelli et al, 2003;Chen et al, 2005).…”

“…The addition of 5 to 20 % egg white in egg yolk also leads to a decrease in egg yolk viscosity in the range of 6-90 % (Li-Chan et al, 1995).The resistance of the vitelline membrane is decreased when eggs are submitted to vibrations during transport and storage, and especially at high temperature (Berardinelli et al, 2003;Chen et al, 2005). According to Lechevalier et al (2005), 70 % of the variability of the foaming properties of pasteurised egg white is due to changes in storage temperatures of table eggs upstream of the breaking process.…”