Preservação da qualidade pós-colheita de atemóia com uso do 1-MCP

Abstract

The increase in respiratory activity in Annonaceae is accompanied by rapid changes in the chemical composition of the fruit, making the flavour and aroma very pleasant. However, there is a very quick decrease in pulp firmness. Thus, this study aimed to extend the postharvest conservation of Atemoya through the use of I-methylcyclopropene (1-MCP), modified atmosphere associated with cooling. Atemoyas were picked up at physiological maturity stage, sanitized and air dried, after they were treated with the concentrations 0, 200, 400 and 600- nLL-' 1-MCP for 8 hours, in ambient temperature. After that, the fruit were placed in polystyrene trays. Some of them remained without wrapping and the others were wrapped with plastic membrane of LDPE 16um. The evaluated variables were: loss of fresh weight, dimensions (length and diameter), firmness, soluble solids, titratable acidity, soluble solids / acidity ration, pH, total soluble sugars, reducing and non-reducing sugars, starch, concentration of CO; and ethylene, isolation and identification of fungi. The experiment was carried out in a completely randomized design in split-plots, having in the parcels the four doses of 1-MCP (0, 200, 400 and 600 nL.L-'), and in the split-plots the six evaluation times after harvest, every five days, with four replications and four fruits per experimental unit. The use of modified atmosphere allowed storage of 25 days, with suitable quality of the physical and chemical attributes, while the fruits without wrapping presented better quality in the highest concentrations of 1-MCP making possible a storage of 20 days. The fruits treated with 1-MCP. showed themselves firmer, delays in soluble solids accumulation and in starch’s degradation. The coloration also was preserved by 1-MCP, it verifying in the treated fruits luminosity, cromaticidade and Hue® angle superior to fruits without treatment. The dose of 600 L.L" was the most efficient in keeping the physical and chemical characteristics.