Cocoa Butter

COCOA BUTTER (Oleum or Butyrum Cacao F VII) is obtained as a byproduct in the production of so-called Dutch cocoa and chocolate; it is pressed in a press heated to 70–80° from roasted, husk-free, ground cacao tree beans—Theobroma Cacao L., Theobroma bicolor Humb., and other species of Theobroma, mixed with 10% water. Cocoa butter is separated from water by collecting the fat that solidifies upon cooling; it is purified by further melting and filtration. Cacao beans contain from 45% to 55% fat. Cacao press cake, which retains 10–15% fat, is used in chocolate manufacture. Cocoa butter is solid at room temperature, but melts already at 30–34°; it has a yellowish hue, and a pleasant, delicate odor and taste of roasted cacao beans. Cocoa butter consists mainly of stearin, palmitin, arachin, a small amount of linolein, and a negligible quantity of glycerides of formic, acetic, and butyric acids. Unlike other oils, cocoa butter is soluble in 5 parts by weight of anhydrous alcohol, but only negligible amounts are soluble in 90% alcohol. The absence of wax and foreign fats in cocoa butter is established by its complete solubility in 2 parts by weight of ethyl ether, and this solution must not produce turbidity or sediment within twenty-four hours, which would appear in the presence of admixtures of tallow, waxes, paraffin, etc. White or light-bleached cocoa butter is often colored with an artificial organic yellow pigment (butter yellow), which turns red in the presence of acids. To detect this pigment, 3–4 g of cocoa butter is melted in a test tube, 3–5 cm³ of ethyl ether is mixed in, 2–3 cm³ of HCl of specific gravity 1.18–1.19 is poured in, and shaken; in the presence of the pigment, the acid layer is colored red. An admixture of fat from cacao husk is recognized by its high acid number, reaching 50, and an increased iodine number (39–40). The acid number of fresh oil is 1.1–2.4; specific gravity at 15° is 0.945–0.979; iodine number is 32–38; saponification number is 192–202; Reichert-Meissl number is 1.6 (for methods of determining constants, see Fats). In medicine, cocoa butter, as an indifferent, non-drying, easily fusible fat, is used either by itself or mixed with medicinal substances in the form of suppositories or globules. For this purpose, cocoa butter must contain as little free fatty acids as possible, which can cause local irritation. This is especially necessary to keep in mind during the industrial preparation of suppositories and globules, since the amount of free fatty acids increases in cocoa butter during storage; preparations for future use are best made with neutralized cocoa butter, and also in the form of cocoa ointment, consisting of 1 part cocoa butter and 2 parts Provence oil. In cosmetics, cocoa butter is used for making pomades. Cocoa butter exhibits weak absorbability compared to other fats. In confectionery, cocoa butter is used for the manufacture of chocolate, especially for its fast-melting varieties (mignon, etc.).