Respiration rate as indicated by CO2 production was measured by placing two tomato fruit in 1 L plastic container for 1 h, and 1 mL of gas sample was withdrawn from the headspace with a gas tight hypodermic syringe and analysed with a gas chromatograph (GC) (Claru-500, Perkin Elmer, USA) equipped with a stainless steel column (Porapak R 80/100)