Ethylene and ripening in melons

For the first time it has become possible to measure the ethylene concentration of the internal atmosphere of fruits. Melons, with their large cavities, are easiest to study, but by using small hypodermic syringes a sample of gas can be sucked out of almost any fruit. An ultrasensitive gas chromatograph then can be used to measure the amount of ethylene, even as low a concentration as one part per billion.