Variation in ethylene production and respiration rate for Norwegian grown plums (Prunus domestica L.) in relation to packaging parameters.

摘要

Knowledge of the respiration rate of a fresh produce is a key factor in the choice of appropriate packaging. Ethylene and CO₂-production and O₂-consumption were measured for nine Prunus domestica plum cultivars grown on the west coast of Norway. Respiration and ethylene production were measured at 2 degrees C and 6 degrees C over two seasons. For three cultivars measurements were made at two or three maturity stages of the plums. Ethylene production ranged from 0.2 to 4.1 and 0.3 to 4.8ml ethylene/kg-1h-1 at 2 degrees C and 6 degrees C, respectively. CO₂-production ranged from 2.6 to 4.8ml CO₂/kg-1h-1 at 2 degrees C and from 4.0 to 7.3 CO₂/kg-1h-1 at 6 degrees C. O₂-consumption ranged from 2.5 to 4.8ml O₂/kg-1h-1 at 2 degrees C and from 4.4 to 8.0 O₂/kg-1h-1 at 6 degrees C. On average, ethylene production, CO₂-production and O₂-consumption rate values were 21%, 54% and 66%, respectively, higher at 6 degrees C compared to 2 degrees C, indicating that respiration rate was more sensitive to temperature changes than the ethylene production. Some seasonal differences in respiration rate and ethylene production were measured for some of the plum cultivars. 'Victoria' had a typical climacteric fruit pattern, whereas ethylene production of 'Reeves' increased with maturity stage, but had an atypical respiration rate. Ethylene production in 'Jubileum' was low (0.2 and 0.3ml ethylene/kg-1h-1 at 2 degrees C and 6 degrees C, respectively) and did not climax. In general, the relatively high postharvest respiration rates of Norwegian plums combined with low sensitivity to high CO₂-concentrations imply that commercial micro or macro-perforated packaging materials for plums should have high gas transmission rate