Effects of Temperature and Ethylene Removing Agents on Respiration of Mature-green Mume (Prunus mume Sieb. et Zucc.) Fruit held under Air and Controlled Atmospheres

Abstract

Mature-green mume (Japanese apricot, Prunus mume Sieb. et Zucc.) fruit from four culti- vars (Gojiro, Nankou, Hakuoukoume, Shirakaga) was held under air and 3 5% O₂ • 9 10% CO₂ gas stream with or without ethylene removing agents (ERA) for 7 days at 25°C to investigate the effect of ERA on respiration. 'Hakuoukoume' fruit was also held under various controlled atmospheres (CA) for 10 days at 10°C and 8 days at 25°C to investigate the influence of storage temperature.
1. Mume fruit exhibited the climacteric respiratory pattern under of air and CA at 25°C, irrespective of ERA. The onset, however, or duration of the climacteric rise was delayed or prolonged with ERA. ERA was more effective under CA than under air. The delay of onset or retardation on duration of the rise with ERA was inversely proportion al to the logarithmical values of the maximum concentrations of residual ethylene.
2. The respiration rate of mume fruit approaching climacteric peak was reduced with CA, but unaffected with ERA.
3. The O₂ uptake rate of 'Hakuoukoume' under air at 10°C, was reduced to 1/5 of that at 25°C. The rate was further reduced under various CA, especially under high CO₂ con- centration at 10°C.
4. CA of 3 5% O₂ • 9 10% CO₂ combined with ERA was effective in keeping quality of mume fruit at 25°C. The O₂ consumption during the first 3 days of storage under this condition was reduced to 60 90% of that under CA without ERA, and to 20 to 40% of that under air without ERA.
5. To market ERA-treated mume fruit with good quality stored at ambient temperature, the storage period should be limited to within 4 days; and the ERA should be applied at the preclimacteric stage. To store fruit for a longer period, recommend that they be kept under 4 5% O₂ and 8 9% CO₂ and 10°C.