In addition, a feature of the process according to the invention can also be that cooling and retrogradation are performed according to a temperature-step program in a temperature range from 100 to 0??? C., and preferably from 90 to 4??? C., for a total time period of from 8 to 36 h, preferably from 20 to 28 h, and in particular from 22 to 26 h, according to the following temperature-time program