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

• Ethylene production ranged from 0.2 to 4.1 and 0.3 to 4.8 ml ethylene/kg−1 h−1 at 2 °C and 6 °C, respectively.
• CO2-production ranged from 2.6 to 4.8 ml CO2/kg−1 h−1 at 2 °C and from 4.0 to 7.3 CO2/kg−1 h−1 at 6 °C.
• Respiration rate was more sensitive to temperature changes than the ethylene production.
• Seasonal differences in respiration rate and ethylene production were measured for some of the plum cultivars.
• Packaging materials for plums should have high gas transmission rates.

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 °C and 6 °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 4.8 ml ethylene/kg−1 h−1 at 2 °C and 6 °C, respectively. CO2-production ranged from 2.6 to 4.8 ml CO2/kg−1 h−1 at 2 °C and from 4.0 to 7.3 CO2/kg−1 h−1 at 6 °C. O2-consumption ranged from 2.5 to 4.8 ml O2/kg−1 h−1 at 2 °C and from 4.4 to 8.0 O2/kg−1 h−1 at 6 °C. On average, ethylene production, CO2-production and O2-consumption rate values were 21%, 54% and 66%, respectively, higher at 6 °C compared to 2 °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 0.3 ml ethylene/kg−1 h−1 at 2 °C and 6 °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.