Abstract
In order to investigate the effects of postharvest application of 1-methycyclopropene (1-MCP) on the ripening of 'Tainung 1' papaya, an experiment was carried out at the Embrapa Cassava & Tropical Fruits Research Center in Cruz das Almas, Bahia State, Brazil. Fruit were harvested at the color break stage, washed and immersed in water with 100 ppm free chlorine for 3 minutes and air dried. Fruit were treated with gaseous 1-MCP (100 or 300 nL L-1), obtained by dilution of the commercial powder(SmartFresh) in water in hermetically sealed chambers (186 L) during 12 hours at 22 degrees C. Control fruits were held in air. Subsequently, fruits were allowed to ripen at 27 degrees C and 80% relative humidity. Quality evaluations were assessed on four fruit replicates on the day of harvest and every 3 days during days for epidermal color, pulp firmness, soluble solids content, and total titrable acidity. 1-MCP effectively delayed epidermal color developement and strongly affected pulp firmness. Treated fruits reached the >75% yellow stage 6 days later than the control for both concentrations. Control fruit softened rapidly (in 3 days), while fruit treated with 1-MCP at 100 nL L-1 did not soften significantly until after 12 days of storage; those treated with 300 nL L-1 showed the first sign of softening after 12 days. The results showed that 1-MCP is highly effective in delyaing ripening of 'Tainung 1' papayas. The effects were stronger with 300nL L-1.
