Submitted to: National Egg Quality School Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/26/2006
Publication Date: 5/22/2006
Citation: Jones, D.R. 2006. Haugh unit assessment. National Egg Quality School Proceedings. p 123-124.
Technical Abstract: The Haugh unit was developed in 1937 by R. Haugh and is revered as the “gold standard” for measuring interior egg quality. This objective method of interior quality determination is based on a correlation of egg weight and height of the thick albumen. Most people associate the determination of interior egg quality with candling eggs. While this is the most commonly utilized method, it is also very subjective. USDA Agriculture Marketing Service (AMS) has published specific guidelines for Haugh unit readings and egg grades (AMS 56.210). Haugh units are determined with the aid of a micrometer, balance, and level, flat surface (such as an egg break-out table). A break-out table can be useful during measurements because the mirror allows the operator to determine exactly when the micrometer comes in contact with the thick albumen surface. Due to current technology available, there are now manual and electronic methods for determining Haugh units.