The present invention relates to an effective process for converting animal-derived protein-containing material into a peptone mixture. The process comprises a step involving alkaline hydrolysis of the protein-containing material. The hydrolysis step can be rapid and typically requires only a low concentration of alkaline material. The overall conversion process can produce a high yield of small peptones and other peptones. The resulting peptones may be further separated, purified or otherwise processed to provide desired properties such as molecular weight distribution, water solubility, dry color and dry flowability.