Energy efficient heating or cooling of foodstuffs

摘要

Changing the temp. of foodstuffs comprises contacting the immediate vicinity of the goods to be cooled with a liq. medium bearing the desired temp. The medium being cooled or heated externally.Also claimed are (i) method of heating foodstuffs using a low boiling metal having a m.pt. less than 200 deg.C as a heat-transfer agent, and (ii) an appts. for changing the temp. of foodstuffs having hollow regions located in the immediate vicinity of the goods to be cooled or heated.Pref. the cooling liq. is centrally cooled, pref. at least partially using the temp. of the surrounding air or drinking water, or heated, pref. at least partially by means of solar energy or recovered heat, and stored in an insulated vessel. The cooling liq. is pref. an oil, esp. a multi-purpose oil or a silicone oil, having a curdling pt. less than 0 deg.C, or an emulsion of a liq. and solid particles, pref. metals to improve heat conductivity or amorphous materials (esp. quartz sand) to improve heat storage capacity. Pref. heat exchange takes place centrally and the liq. is directed along pipes to individual cooling or heating regions that come into direct contact with the foodstuffs. The liq. is pref. stored in an insulated vessel and is transferred therefrom to a stationary heat exchanger.