Influence of dose characteristics on efficiency of electron beam sterilization of fish preserves

In previous paper we reported that maximum efficiency of gamma-ray sterilization of fish preserves, that does not influence the product quality, is at the dose rate of 1.5 Gy/s and absorbed dose of 6 kGy. However, effect of increase in the dose rate by two or more orders on optimal antibacterial dose and the product quality level is still not known. In this paper we present data on influence of dose rate and absorbed dose on efficiency of electron beam sterilization of fish preserves. Fish preserves were prepared 5 days before electron processing. For e-beam irradiation the impulse electron accelerator ILU-10, produced by the Budker Institute of Nuclear Physics in Novosibirsk was used. The energy of the accelerator is 5 MeV, delivered doses ranged from 1.5 to 6.0 kGy. Unirradiated preserves were used as control. The product was kept at the temperature ranged from +5 to +8 оС. Irradiated samples were tested on the 10th, 95th and 185th days after electron beam processing. On the 15th day after preparing the total content of mesophilic aerobic and facultative anaerobic microorganisms and yeast in the control samples was100 times and 1.5 times higher than the norm, respectively, concomitant early imbalance of organoleptic indicators was observed. At the same time, all indicators in sterilized samples were within normal limits. Maximum antibacterial effect was at the radiation dose of 6.0 kGy. During the storage no deterioration was observed. Results of the study allow us to conclude that electron beam irradiation of fish preserve at 3-6 Gy using electron accelerator does not cause deterioration of the quality of preserves, guarantees their microbiological safety and extends their shelf life.