収穫後チャービル株の外観品質維持のための弱光照射ＣＡ貯蔵最適条件

Abstract

Whole chervil (Anthriscus cerefolium L.) harvested in a commercial operation was placed in a plastic container at 5°C under different CO2 concentrations (0.05, 0.5 or 1.0%) and PPFDs (photosynthetic photon flux density ; 0, 0.5, 1.0 or 2.0μmol m-2 s-1) to determine CO2 exchange rate at an atmospheric O2 conc. of 20%. The CO2 exchange rate was calculated from the difference between CO2 conc. of outflow and inflow air (flow rate : 4.8L h-1) through the plastic container. The CO2 exchange rate decreased with increasing CO2 conc. or increasing PPFD. Relationship of CO2 conc. and PPFD where the CO2 exchange rate becomes 0 was obtained by drawing a 3-dimensional (CO2 conc., PPFD and CO2 exchange rate) graph. Three combinations of CO2 conc. and PPFD (0.05%+ 1.6μmol m-2 s-1: C0.05P1.6 ; 0.5%+0.5μmol m-2 s-1: C0.5P0.5 ; 1.0%+0.2μmol m-2 s-1: C 1.0P0.2) were then selected among the relationship for the following storage experiment. Whole chervil was stored at 5°C and at O2 conc. of 20% for 27 d under the conditions of the 3 combinations or under the usual low temperature storage conditions (0.04%+0 pmol m-2 s-1: Cont) as control. The color difference (ΔEab) values of the leaves of chervil in Cont, C0.05P1.6, C0.5P0.5 and C1.OPO.2 on the last day of storage (day 27) were 36, 22, 10 and 17 respectively, and there were significant differences among those values each other. The ΔEab values in Cont, C0.05P1.6, C0.5P0.5 and C1.0P0.2 were kept less than 9 until day 6, day 12, day 24 and day 15 respectively. A five-rank subjective visual quality score of chervil on day 27 in C0.5P0.5 was significantly higher than those in Cont and C0.05P1.6, and that in C 1.0P0.2 was significantly higher than Cont. These results indicate that the optimum conditions, at 5°C and at O2 conc. of 20%, of low light irradiation-CA storage for preservation of the visual quality of postharvest whole chervil exist around the combination of 0.5%CO2 and 0.5μmol m-2 s-1 PPFD.