1-Methylcyclopropene (1-MCP) and dynamic controlled atmosphere (DCA) applications under elevated storage temperatures: Effects on fruit quality of 'Elstar', 'Jonagold' and 'Gloster' apple (Malus domestica Borkh.)

The effects of 1-methylcyclopropene (1-MCP), dynamic controlled atmosphere (DCA) and combination of both on fruit quality of 'Elstar', 'Jonagold' and 'Gloster' apple (Malus domestica Borkh.) were tested at three different storage temperatures. 1-MCP treatment and DCA storage prolonged storage- and shelf-life as indicated by delayed loss of firmness and titratable acids (TA) in all three cultivars. 1-MCP was more effective than DCA especially in prolonging shelf-life. At higher storage temperature of 3.5-10 degrees C best results were achieved by the combination of 1-MCP plus DCA. Fruit firmness of apples stored under these conditions was similar or even superior to firmness of fruit stored under standard ULO conditions at 2 degrees C. The current commercial firmness demand were fulfilled in most cases even at higher storage temperature. However, TA reduction by higher temperature could not be effectively slowed down by 1-MCP, DCA or the combination of both. 1-MCP treatment promoted the development of skin spots in 'Elstar' apples. The combination of 1-MCP and DCA led to less skin spots than 1-MCP alone, whereas DCA alone was most effective in reducing incidence of skin spots. Internal browning in 'Elstar' apples was increased by higher temperature, by 1-MCP and to a lesser extent DCA treatments whereby DCA moderated the negative effect of 1-MCP. Higher temperatures promoted the dissipation of watercore in 'Gloster' apples, resulting in reduced injury from associated internal browning. In contrast, 1-MCP reduced watercore dissipation and increased internal browning while DCA had no negative effect on watercore. Moreover, DCA prevented the transformation of watercore to flesh browning in 1-MCP treated apples. It was concluded that the combination of 1-MCP and DCA storage is more favorable than 1-MCP or DCA alone especially at higher storage temperature.