It is a colorless oily liquid with an odor that is fatty, cheesy, waxy, and like that of goats[1] or other barnyard animals.
It is a fatty acid found naturally in various animal fats and oils, and is one of the chemicals that gives the decomposing fleshy seed coat of the ginkgo its characteristic unpleasant odor.
[1] Salts and esters of caproic acid are known as caproates or hexanoates.
Along with caproic acid, they account for 15% of the fat in goat's milk.
Caproic, caprylic, and capric acids (capric is a crystal- or wax-like substance, whereas the other two are mobile liquids) are not only used for the formation of esters, but also commonly used "neat" in: butter, milk, cream, strawberry, bread, beer, nut, and other flavors.