Abstract
This investigation was carried out to find the methods that onions were safely maintainable good quality during storage under cold weather conditions in Hokkaido. The quality of onions during storage was affected by the injury at mechanical havesting, and the thermal conditions of a storehouse.
The author investigated the rate of onion bulbs injured by an onion havester, the changes of atmosphere in the storehouse, and the inside temperatures of an onions bulbs.
The results are summarized as follows.
1. About 80 percent of bulbs was injured by the onion harvester, but these were almost cured under the conditions of relative high temperature and low humidity in a laboratory.
2. The inside temperatures in the storehouse were closely related to the open air temperature.
3. The minimum temperature of onion bulbs in the container which was nearly located beside the wall showed -4deg.C.
4. The relative humidity of central part of the storehouse were elapsed about 80 percent a little heigher than 70-75 percent of the appropriate humidity for storage.