ARS | Publication request: Effects of processing on barriers of bacterial invasion in shell eggs and egg products

Submitted to: UJNR Food & Agricultural Panel Proceedings
Publication Type: Proceedings
Publication Acceptance Date: October 1, 2007
Publication Date: November 1, 2007
Citation: Musgrove, M.T. 2007. Effects of processing on barriers of bacterial invasion in shell eggs and egg products. UJNR Food & Agricultural Panel Proceedings.p.115-118.

Technical Abstract: To project a developing embryo, there are many physical and chemical barriers inherent in eggs for the prevention of invasion by bacteria and other microorganisms. As versatile as they are nutritious, eggs are subjected to many types of processing – from washing, grading, and packing shell eggs to liquid pasteurization and drying of various components. In the U.S., most eggs are marketed in the shell. Following washing, shell eggs are treated with sanitizing solutions. Depending on the chemistry of the sanitizer, egg shell quality may be affected as much as associated microbial populations. Four of the most common liquid products are whole egg, whole albumen, 10% sugared yolk, and 10% salted yolk. It is important to consider the changes affected by egg processing that can affect natural defenses as well as nutritional and functional properties. Consumers care about safety as well as quality and in a post 9/11 world, concerns over security risks must also be considered. Studies were conducted to determine growth patterns of Salmonella Typhimurium DT104 in four commercial liquid egg products held at 4, 10, 20, 30, 37, and 42oC for 0 to 384 h. All experiments were performed in duplicate and repeated twice. Standard methods were used to estimate cellular numbers and log CFU/g egg product was plotted against time. Maximum Salmonella cellular density increased to 8-9 log CFU/g whole egg or sugared yolk, increased by 1 log in liquid albumen but was decrease 99% in salted yolk. Other serotypes of Salmonella reached comparable densities when incubated at similar temperatures.