Effect of 1-methylcyclopropene and ozone on the quality of broccoli
C.F. Forney, J. Song , L. Fan, P.D. Hildebrand, M.A. Jordan and D.A.J. Ryan
Proceedings of 26th International Horticultural Congress. Volume of Abstract . Toronto, Canada, 11-17 August, 2002. Abstract S09-P-47. pp. 239.
2002
บทคัดย่อ
Fresh broccoli florets (Brassica oleracea L. Italica group) were treated with or without 1 uL.L-1 methylcyclopropene (1-MCP) for 14h, and then stored at 10 oC with 0,200, or 700 nL.L-1 ozone. Samples were evaluated after 1, 2, 5, 8, or 12 days of storage. Treatments with 1-MCP delayed the yellowing of florets, and at day 5 the hue angle of 1-MCP treated florets was 116 compared with 102 for the controls. Respiration roat of florets was reduced by 1-MCP for the first 5 days and ethylene production was stimulated during the first 2 days following treatment. The 1-MCP treatment maintained higher chlorophyll fluorescence expressed as Fv/Fm during 12 days of storage. Also, 1-MCP inhibited dimethyl tresulfide production, which contributes to off-order development in broccoli florets. Compared with controls, florets stored in 200 nL*L-1 ozone had less mold growth, but no differences were observed in color, respiration, ethylene production, or chlorophyll fluorescence. Florets stored in 700 nL.L-1 ozone were greener at day 12 than florets held in air or 200 nL.L-1 ozone, but interestingly, chlorophyll fluorescence decreased significantly. At day 12, Fv/Fm was only 30% of its initial value. Storage in 700 nL.L-1 ozone stimulated respiration and ethylene production of florets after 1 day of storage, and caused stem browning of florets. A synergistic effect of 700 nL.L-1 ozone and 1-MCP on respiration and ethylene production was found. The 1-MCP on respiration and ethylene production was found. The 1-MCP, 200 nL.L-1 ozone, and 200 nL.L-1 ozone plus 1-MCP treatments were considered to be suitable to maintain the quality and extend the shelf-life of broccoli florets stored at 10 oC.