CORRELATION OF EGG PHYSICAL QUALITY MEASUREMENTS AND FUNCTIONAL DETERMINATIONS

Authors: Jones, Deana; Musgrove, Michael

Submitted to: World's Poultry Science Journal
Publication Type: Proceedings
Publication Acceptance Date: 6/21/2006
Publication Date: 9/11/2006
Citation: Jones, D.R., Musgrove, M.T. 2006. Correlation of egg physical quality measurements and functional determinations. World's Poultry Science Journal. Verona, Italy, September 10-14, Poster Session. EPC Proceedings (http://10.11.10.181:4001/fullpapers/10415)

Interpretive Summary: Eggs can serve in many roles in the food system. They can be the source of nutrition for an incubating chick, impart characteristic taste or texture to a food product, provide leavening to bakery products, retard crystallization in foods and candies, and many other functions. The definition of egg quality is dependent upon a given situation. Over the years, physical characteristics and functionality have been utilized to measure egg quality. Initially, the physical characteristics of the egg and its components were assessed to determine if an egg was “good”. Many of the original physical quality determinations were subjective in nature, but subsequent objective methodologies were developed. Conducting functional tests can be a challenge on many levels. Many functional tests require specialized equipment which often can not be utilized for other laboratory procedures. Many of the methods require the use of a stove or oven. Furthermore, the subjective nature of the results often make it difficult to compare findings between laboratories or even between laboratory personnel conducting the experiments. Functional tests can also be labor intensive. The current results indicate that many physical quality measurements can be correlated to the functionality of the egg and its components. Albumen height and Haugh units were found to have significant correlations with all functional tests conducted in the current study. Therefore, these common egg quality screening techniques could be utilized to predict the functional outcome of a given lot of eggs.

Technical Abstract: Both physical and functional determinations have served as a means for determining shell egg quality. A study was conducted to determine if correlations exist between these types of egg quality measurements. Shell eggs were collected weekly after processing from a U.S. inline processing facility for three weeks (replicates). Eggs were stored at 4C until testing was conducted. The study was conducted during 10 wks of storage. The physical quality parameters monitored include: egg weight, albumen height, Haugh unit, shell strength, vitelline membrane strength and elasticity, and egg solids. Functional measurements included: angel food and sponge cake volume and mayonnaise depression force (fresh and stored). Angel food cake volume was found to be positively correlated with increased egg weight (P < 0.001), albumen height (P < 0.01), and Haugh unit (P < 0.01), while negatively correlated with increased albumen solids (P < 0.01). Sponge cake volume was positively correlated with increased whole egg solids (P < 0.01) and negatively correlated with egg weight (P < 0.001), albumen height (P < 0.01), Haugh unit (P < 0.01) and vitelline membrane elasticity (P < 0.01). Fresh and stored mayonnaise force measurements were highly correlated (P < 0.0001). Yolk solids were positively correlated with fresh and stored mayonnaise force measurements (P < 0.0001 and P < 0.001, respectively). The results of this study found several strong correlations between objective physical egg quality measurements and more subjective functional quality determinations which could lead to greater use of objective physical assessments to determine functional capabilities of shell eggs.