In order to provide a product that is suitable as fat substitute in foods, which can be produced simply and inexpensively and is deemed safe from the nutritional physiology viewpoint and with which the typical texture of fat-containing foods can be simulated as favorably as possible, particles of collagen material are proposed which are substantially insoluble and swellable in water, wherein in swollen state the particles have an average diameter of less than approximately 150 μm. A process for the production of this product is additionally proposed.