The in situ encapsulation process is due to its few process steps an innovative and cost effective alternative to common encapsulation techniques. It combines the well-known processes of pastillation and crystallization. This concept is proven with case studies of three xylitol capsules which vary in composition and size. It could be shown that the knowledge concerning the solubility of the components is essential to determine the suitable production conditions. The application of seed crystals and the temperatures during the process have major effects on the capsules quality. A fast crystallization of the capsules results in an instable shell. However, with increasing layer thickness of the shell, the crushing force that needs to be applied to break the capsules is increasing as well. But the stability which is related to the capsules size is decreasing with increasing diameter, even though layer thickness and crushing force are increasing, too.