Method for judging solubility and strength of solid milk and method for producing solid milk

摘要

[Problem] The object of invention is to provide solid milk with favorable solubility and enough strength and the method of manufacturing the solid milk. [Means] A solid milk which comprises a hard layer at the surface (12) of the solid milk, and a central area (11) of the solid milk, the central area (11) being inside the hard layer, characterized in that the hard layer comprises 10wt% to 50wt% of crystalline lactose and has a thickness of 0.5 mm or more, wherein the amount of crystalline lactose at the hard layer is larger than that of crystalline lactose at the central area (11). The solid milk of the invention has X-ray diffraction pattern of its surface area that has a main peak of 2theta= 10 - 15 degrees at 2theta = 10 - 11 degrees or at 2theta = 12 - 13 degrees. A method for the manufacture of solid milk comprises compressing powdered milk to obtain compressed powdered milk; humidifying the compressed powdered milk to obtain humidified compressed powdered milk; and drying the humidified compressed powdered milk to obtain the solid milk. A part of amorphous lactose at the surface of the solid milk 12 is crystallized at the steps of humidifying step and drying.