Submitted to: Poultry Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/28/2001
Publication Date: 5/1/2002
Citation: Jones, D.R., Tharrington, J.B., Curtis, P.A., Anderson, K.E., Keener, K.M., Jones, F.T. 2002. Effects of cryogenic cooling of shell eggs on egg quality. Poultry Science. 81:727-733. Interpretive Summary: Shell eggs are traditionally cooled by placing them in a 45F cooler after processing. One problem with this current method is that it can take to 14 days for eggs to achieve 45F in this environment. In this study we investigated the effects of post-processing rapid cooling on shell egg quality. Gaseous nitrogen (GN), liquid nitrogen (LN), and gaseous carbon dioxide (GC) were utilized to rapidly cool eggs in a commercial egg proces facility and were compared to traditional cooling (TC). Quality factors an USDA shell egg grades for quality defects were measured. Egg quality was enhanced by rapid cooling compared to traditionally cooled eggs. Use of this technology could allow for egg quality to be maintained fo a longer period of time. This could increase foreign markets and potential lead to extended shelf lives.
Technical Abstract: This study was conducted to investigate the effects of cryogenic cooling on shell egg quality. Gaseous nitrogen (GN), liquid nitrogen (LN), and gaseous carbon dioxide (GC) were utilized to rapidly cool eggs in a commercial egg processing facility and were compared to traditional cooling (TC). A modified food freezer was attached to existing egg processing equipment in order to expose eggs to the selected cryogen. In experiment one, eggs were treated with GN, LN, and TC then stored and tested over ten weeks. Experiment two eggs were treated (GC and TC) and evaluated for twelve weeks. Quality factors that were measured included Haugh units, vitelline membrane strength and deformation at rupture, and USDA shell egg grades for quality defects. Haugh unit values were greater for cryogenically treated eggs as compared to traditionally cooled eggs (73.27, GN; 72.03, LN; and 71.4, TC; experiment one and 74.42, GC and 70.18, TC, experiment two). The percentage of loss eggs in the GN treatment was significantly (P < 0.01) greater compared to the LN and TC treatments. Vitelline membrane strength was greater for the cryogenically cooled eggs versus traditional processing. Vitelline membrane breaking strength decreased over time of storage. Vitelline membrane deformation at rupture was significantly (P < 0.05) greater for the cryogenically cooled eggs compared to the traditional eggs in each experiment. Use of the technology could allow for egg quality to be maintained for a longer period of time. This could increase foreign markets and potentially lead to extended shelf lives.