PHYSICOCHEMICAL, MICROBIOLOGICAL AND SENSORY EVALUATION OF FREEZE-DRIED EGGS STORED AFTER IRRADIATION

摘要

An experiment with freeze-dried whole hen's egg has been carried out to study the efficacy of the combination of two methods used for the preservation of foodstuffs - freeze-drying and irradiation with optimal dose of gamma rays, in order to prolong its shelf-life as well as to guarantee its microbiological safety. The physicochemi-cal, microbiological and organoleptic characteristics of the freeze-dried egg mnlange were determined. During the 4-year period of storage at room temperature of the freeze-dried (control group) and the freeze-dried and irradiated with a dose up to 3.5 kGy melange no significant changes were found into the sensory characteristics till the 28~th month, while the physicochemical ones stayed unaltered. The quantity of thiobarbituric acid reactive substances (TEARS, meaning milligrams malondialdehyde equivalent per kilogram) in the irradiated samples was in parallel increase with the dose till the 6th month of the time of storage, while after that it was decreasing. The microbiological features of the irradiated freeze-dried eggs have been improved during storage. The mathematical processing of the data showed that the time of storage (F_A) was the main factor for the slight changes established, while gamma irradiation hadno essential influence.