The respiration rate measurement of fresh produce using automated flow-through system.
Lee H.D., Yoon H.S., Lee W.O., Jeong H., Choi J.U.
5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.72
2004
บทคัดย่อ
The respiration rate measurement of fresh produce using automated flow-through system.
This study was conducted to measure the respiration rate of fresh produce using an automated measuring system based on the flow-through measurement method under the various gas compositions.The developed system was consisting of mainly two parts; one is a gas mixture generator, and another is a gas analyzer.The gas mixture generator consists of precision pressure regulators, manipulators, and metering valves.The volume flow rate of O2, CO2 and N2 (balanced with N2), which were supplied from cylinders, was controlled by the precision pressure regulator and metering valve to obtain the desired gas mixture.The measuring part consists of multi-position valve, sample loop and gas chromatography.The gas flow line is connected to multi-position valve, which separates inlet and outlet from gas mixture of chamber.Therefore it is possible to analyze gas sample by gas chromatography according to the flow through method.The gas mixture generators make a gas mixture as + 0.2% accuracy via desired gas concentration from the 0.0 to 20.6%.The empty chamber test, gas concentration difference of inlet and outlet from chamber is + 0.02%.When the gas sample was analyzed three times at each gas flow line (inlet and outlet), the measuring repeatability was + 0.03%.The result of respiration rate measurement about tomatoes and apples at 12 °C were: O2 consumption rate of tomatoes, 2.0-8.2 mg kg-1 h-1; CO2 evolution rate of those, 3.5-6.9 mg kg-1 h-1; O2 consumption rate of apples, 0.8-2.8 mg kg-1 h-1 and CO2 evolution rate of those, 0.7-4.8 mg kg-1 h-1 according to gas compositions.The measurement values of automated system were similar to values from the literature.