Sterilization of ready-to-cook Bibimbap by combined treatment with gamma irradiation for space food

Bibimbap, Korean traditional cooked rice mixed with various kinds of vegetables, together with mushrooms and a ground meat, and seasoned with red pepper paste, was developed as a ready-to-cook food by combined treatment with irradiation for the use in space. By gamma irradiation of 25 kGy, the total aerobic bacteria of Bibimbap that was initial by 6.3 log CFU/g decreased to below detection limit, but its sensory qualities were drastically decreased. To enhance the sensory quality, the effects of antioxidant in Bibimbap were evaluated. A treatment with 0.1% of vitamin C, vacuum packaging and gamma-irradiated at 25 kGy and −70 °C showed higher sensory scores than only the irradiation process. This result indicates that the radiation technology may be useful to produce a variety of space foods with high quality of taste and flavor, when combined with other methods. - Highlights: ► The combination treatment with gamma irradiation was developed for the production of space Bibimbap. ► This combination treatment increased the sensory properties of Bibimbap. ► The developed Bibimbap was certified as a space food by Russian Institute of Bio-medical Problems through the sheld-life test.