The use of g-radiation for cold sterilization of multicomponent ready meals

Interest in the use of radiation food processing technologies has increased primarily in order to ensure microbiological safety of food produce and raw agricultural materials and to extend their shelf life. The special interest is focused on application of radiation technologies for processing ready meals, such as fish preserves, that did not underwent previous thermal processing. Schedule of radiation sterilization has not been developed yet and effect of irradiation on quality and shelf life of food have not been fully studied. The purpose of the presented study is to estimate dose of g-radiation for effective killing of microorganisms without reducing quality of preserved food. For study 100 cans of fish preserves were divided into 5 groups, one group was identified as control, the others were irradiated to 0.5; 1.5; 3.0 and 6 kGy doses at a dose rate of 1.5 Gy/s. In 1, 30, 60, 90, 120 days after irradiation organoleptic tests, microbiological analysis and physico-chemical analysis were carried out in compliance with sanitation standards. From study results it is evident that for cold sterilization of fish preserves the most effective gamma-radiation dose was 6 kGy at a dose rate of 1.5 Gy/s. Irradiation to that dose lead to practically complete suppression of vital activity of microorganisms. Minor changes of physic-chemical properties and microbiological indicators of the preserves occurred during the specified shelf life expiration, 3 months, were within limits of norm.