冷蔵庫内の紫外線の効果

抄録

Effect of ultraviolet rayradiation in the refrigerator was investigated. Two refrigerators of the same type were prepared; one irradiated by a 2-watt lamp of ultraviolet rays inside and the other nonirradiated as a control.
Suspensions of a certain concentration of bacilli such as Escherichia coli, Enteritis vibrio parahemolitics, Enteritis Gärtner, Staphylococcus and hay were put and left in the two refrigerators. After a certain hours' storage, the number of colonies was examined. It was found that in the irradiated samples it was reduced to 1/6-1/300, possibly influenced by ultraviolet rays.
Farther, to study a preservative value of ultraviolet rays acting against putrefaction, pH, NH₃ production, protein precipitation, the number of all bacilli per 1g were compared. The results showed the progress of putrefaction in the irradiated samples was 5-6 days slower than in the control non-irradiated, and that the number of bacilli in the air in the refrigerator irradiated decreased, to 1/6. The air contained only a small amount of ozone.