Abstract: For intermediate enrichment of trace substances from a gas stream, a cold ap is used which carries a flow and optionally contains an adsorbent material and which is surrounded by a gas-tight double-walled jacket into which cooling fluid from a surrounding cooling bath can penetrate via an extension tube at the bottom. For desorption, the cooling fluid is expelled from the double-walled jacket via compressed air and a valve control. A pipe loop connected to the double-walled jacket and having a heater winding and circulation pump allows rapid heating of the cold trap. A level control apparatus connected to the compressed-air line allows sensitive level adjustment in the bottom extension tube of the double-walled jacket during the desorption phase. Such a cold trap is advantageous, inter alia, in a chromatography arrangement with a separation column and fractionating column of high resolution and sensitivity.