FUROSINE AS A FRESHNESS PARAMETER OF SHELL EGGS

Furosine, an index of the initial steps of Maillard reaction, has been used for the evaluation of shelf life in UHT milk and of heat damage in various food products. The aim of this paper was to study furosine as an index for egg freshness. Fresh eggs from different hen breeds we re used to assess HPLC method repeatability, to investigate natural va riability of furosine content in fresh shell eggs, and to study furosi ne formation during storage at 5, 20, 30, and 38 degrees C. Furosine, present in fresh egg albumen at a level of about 10 mg/100 g of protei n, increased during storage with dependence on temperature, reaching a fter 40 days at 20 degrees C a level of about 100 mg/100 g of protein. The modification of furosine content in yolk during storage at 20 deg rees C was minimal. Furosine, when measured in albumen, resulted in a very reliable index for egg freshness. In albumen, maximum furosine co ntents of 60 and 90 mg/100 g of protein, respectively, for grades A-ex tra and A eggs commercialized in the European Community are suggested.