2.2. Internal ethylene concentration (IEC)
IEC of each of 10-fruit replicate was measured in fruit at harvest and in untreated and 1-MCP treated fruit at 4 week intervals plus 1 day at 20 C. A 1 mL gas sample from the core cavity of each fruit was injected into a Hewlett Packard 5890 series II gas chromatograph equipped with a flame ionization detector and fitted with a stainless steel column packed with 60/80 mesh alumina F-1 (2 mx2 mm) . The oven, injector and detector temperatures were 200,230, and 245C, respectively. The flow rates for N2, H2 and compressed air were 30, 30, and 230 mL min-1, respectively. IEC was quantified by peak area, and an external standard was used for calibration.