AbstractFully hydrogenated oils, also known as hardfats, are currently employed in a limited number of applications in the food and chemical industries. The use of these compounds has been proposed for the improvement or standardization of the physical properties of lipid systems, showing great potential for use in the production of chocolate, confectionery, and similar products. This work evaluated the addition of different hardfats on the physicochemical properties of cocoa butter (CB). Fully hydrogenated oils with significantly different chemical composition, obtained from palm kernel oil (FHPKO), palm oil (FHPO), cottonseed oil (FHCO), soybean oil (FHSO), and crambe oil (FHCrO), were evaluated for their fatty acid and triacylglycerol compositions. Blends of CB/hardfats, at concentrations of 1, 3, and 5% w/w were studied by determining the melting point, solid fat profiles, microstructure, and consistency. Hardfats FHPO, FHCO, FHSO e FHCrO proved to be effective additives to modulate the physical properties of CB. Major changes on the physical properties of CB were performed by the FHSO. FHPKO was found unsatisfactory as a modifier of the CB.Practical applications: The use of hardfats as crystallization additives in products containing CB is here recommended for technological adjustments of CB formulations in relation to attributes like heat resistance and hardness, often necessary when commercialized in regions of warm climates or with large variation in temperature. The hardfats may act as potential modulators of CB crystallization, aiming to obtain higher quality products and significant cost reduction of industrial processing.