Colza oil

Colza oil is a non-drying oil obtained from the seeds of Brassica campestris, var. oleifera, a variety of the plant that produces Swedish turnips. Colza is extensively cultivated in France, Belgium, the Netherlands and Germany; and, especially in France, the expression of the oil is an important industry. In commerce, colza is classed with rape oil, to which it is very closely allied in both source and properties. It is a comparatively inodorous oil of a yellow color, having a specific gravity varying between 0.912 to 0.920. The cake left after expression of the oil is a valuable feeding substance for cattle. Colza oil is extensively used as a lubricant for machinery, and for burning in lamps.

In France it is used also as a substitute for fine oil in restaurants, as the oil part in a carpaccio, or as the high temperature boiling oil in beef bourguignon. Its taste is different from olive oil. Colza oil, with added color and flavor, has also been fraudulently labeled and sold as olive oil by unscrupulous Italian companies.

Colza oil was also used in Gombault's Caustic Balsam; a popular horse and human liniment at the turn of the 20th century. [Note that the ingredients listed in this link are similar but not the same as the list on the actual bottle.]

Among the more unusual applications of colza oil is the calming of choppy seas, where the oil modifies the surface tension of the water and rapidly smoothes the surface. Rescue and recovery operations have been made far less risky in this way.

More recently, colza has been cultivated in France as an ingredient for biodiesel fuels.