Effect of processing and storage on the chemical quality markers of spray-dried whole egg

Chromatographic techniques were used in order to determine the modifications induced in egg, by a spray-drying treatment, on the native constituents and on the formation of cholesterol oxidation products (COPs) and early Maillard reaction products. The same powdered egg was stored for 12 months at room temperature and at 4 °C, and sampled at 1, 3, 6 and 12 months, respectively. The spray-drying treatment did not affect tocopherol or retinol composition, but caused a severe Maillard reaction (furosine increased from 15 to 500 mg/100 g protein) and accelerated cholesterol oxidation (the sum of COPs increased from 24 to 55 μg/g fat). Only slight modifications were registered in powdered egg stored at 4 °C. During storage at room temperature, however, COPs increased significantly (up to 167 μg/g fat), tocopherols and retinols decreased, whereas furosine was not significantly modified. Thus, furosine can be considered as a suitable technology marker, whereas COPs are important markers of the storage conditions.