La furosina come indice di freschezza dell’uovo in guscio

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 and from the market were used to assess analytical method repeatability, to investigate natural variability of furosine content in fresh shell eggs and to study furosine formation during storage at 5, 20, 30, 38 °C. Furosine, which is present in fresh egg albumen at a level of about 10 mg/100 g protein, increased greatly during storage in dependence of temperature while the modification of furosine content in yolk during storage was minimal. When measured in albumen, furosine resulted a very reliable index for egg freshness. Maximum furosine contents of 60 and 90 mg/100 g protein in albumen are suggested for grades A-extra and A eggs, respectively.