Stable vitamin products for mixing with feed meals, oil cake, bran or mineral supplements are made by distributing vitamin-active substances in an aqueous dispersion of protein, adding a non-toxic coagulant to the dispersion, and drying the coagulum quickly.  Oil, grease or wax dispersions of the vitamin-active substances are preferably emulsified in the protein dispersion; in this connection, Vitamin A, axerophthol acetate and palmitate, Vitamins D2, D3 and E, fish liver oils and concentrates therefrom, palm oil concentrates of Vitamins A, D and E, and such substances in fish oil, peanut oil, palm oil and cocoa butter, are referred to.  Water-soluble vitamins, or substances containing them, e.g. bios, pulverized yeast, yeast autolyzates and plasmolyzates, are added to the protein dispersion directly. Vitamin antioxidants such as lecithin, tannins, gallic acid esters, butyl derivatives of anisole, tocopherols, hydroquinone and nordihydroguaiaretic acid with citric or ascorbic acid may be incorporated; lecithin serves also as an emulsifying agent.  The protein may be from egg, milk, cereal, or oil cake; skimmed milk is particularly suitable.  The coagulant may be rennet or a natural or artificial tannin.  Drying of the coagulum is preferably at 40-80 DEG C. in vacuo.  The dried coagulum may be ground, preferably to yield particles mainly of size 0.85-2.00 mm.  The product may be hardened by heating at 100-105 DEG  C. Vitamins on the surface of granulated products may be washed off with a suitable solvent, e.g. alcohol, acetone, petroleum ether, a chlorinated hydrocarbon, and recovered. Granulated products may be treated with a tannin solution, and may be coated with sucrose. Examples are concerned with (1) adding tannin solution to a mixture of an aqueous dispersion of Vitamin D3 with lecithin, aqueous gelatine and skimmed milk, reconstituted skim milk powder, or milk, separating the coagulum and drying it; (2) adding rennet, at 38-39 DEG  C., to a dispersion in skimmed milk of an oil preparation of Vitamin A with nordihydroguaiaretic and citric acids, heating to 60 DEG  C. and stirring, filtering off and pressing out the coagulum, drying and grinding; (3) adding tannin solution to a dispersion of finely ground yeast impregnated with an oil preparation of Vitamins A and D2 in a liquid obtained by crushing soya beans in water, filtering off the coagulum, drying and grinding.ALSO:Vitamin preparations which retain their activity on storage are made by distributing vitamin-active substances in an aqueous dispersion of a protein, adding a non-toxic coagulant to the dispersion, and drying the coagulum quickly.  Oil, grease or wax dispersions of the vitamin-active substances are preferably emulsified in the protein dispersion; in this connection, vitamin A, axerophthol acetate and palmitate, vitamins D2, D3 and E, fish liver oils and concentrates therefrom, palm oil concentrates of vitamins A, D and E, and such substances in fish oil, peanut oil, palm oil and cocoa butter, are referred to.  Water-soluble vitamins, or substances containing them, e.g. bios, pulverized yeast, yeast autolyzates and plasmolyzates, are added to the protein dispersion directly.  Vitamin antioxidants, exemplified by lecithin, tannins, gallic acid esters, butyl derivatives of anisole, tocopherols, nordihydroguaiaretic acid with citric or ascorbic acid, and hydroquinone, may be incorporated; lecithin serves also as an emulsifying agent.  The protein may be from egg, milk, cereal, or oil cake; skimmed milk is particularly suitable. The coagulant may be rennet or a natural or artificial tannin. Drying of the coagulum is preferably at 40-80 DEG C. in vacuo.  The dried coagulum may be ground, preferably to yield particles mainly of size 0,84-2,00 mm.  The product may be hardened by heating at 100-105 DEG C.  Vitamins on the surface of granulated products may be washed off with a suitable solvent, e.g. alcohol, acetone, petroleum ether, a chlorinated hydrocarbon, and recovered. Granulated products may be treated with a tannin solution, and may be coated with sucrose.  Examples are concerned with (1) adding tannin solution to a mixture of an aqueous dispersion of vitamin D3 with lecithin, aqueous gelatine and skimmed milk, reconstituted skim milk powder or milk, separating the coagulum and drying it, (2) adding rennet, at 38-39 DEG C., to a dispersion in skimmed milk of an oil preparation of vitamin A with nordihydroguaiaretic and citric acids, heating to 60 DEG C. and stirring, filtering off and pressing out the coagulum, drying and grinding, and (3) adding tannin solution to a dispersion of finely ground yeast impregnated with an oil preparation of vitamins A and D2 in a liquid obtained by crushing soya beans in water, filtering off the coagulum, drying and grinding.