**4. Conclusions**

The conditions of the heat treatment of the milk base were more important than the type of enrichment for the physical properties of the gel. These conditions were determined by the heat stability of the mixtures of "versatile" skim sheep milk with WPC or WPHs. The high pressure treatment at conditions that denature almost totally the β-lactoglobulin as an alternative to heating resulted in inferior gel properties, irrespective of the type of enrichment. Supplementation of skim sheep milk with whey protein hydrolysates at > 0.5% had a detrimental effect on gel properties. Finally, the sheep milk base along with the use of fresh traditional yoghurt as a starter, resulted in yoghurt-type gels with high counts of *Lb. delbrueckii* subsp. *bulgaricus* and *Str. thermophilus* -close to the ideal 1:1- and with high ACE-IA, which were not essentially affected by the experimental factors.

**Author Contributions:** Conceptualization, G.M.; Methodology, G.M., P.T. and M.T.; Software, Validation, G.M., E.Z. and L.S.; Formal Analysis, L.S., M.T., E.G., A.K., A.S. and E.Z.; Investigation, G.M. and P.T.; Resources, G.M. and P.T.; Data Curation, L.S., G.M., and E.Z.; Writing—Original Draft Preparation, G.M.; Writing—Review and Editing, G.M.; Visualization, L.S., G.M. and M.T..; Supervision, G.M. and P.T.; Project Administration, G.M. and P.T.; Funding Acquisition, M.G. and P.T.

**Acknowledgments:** This work was supported by the Greek General Secretariat for Research and Technology in the framework of the program SYNERGASIA II\_2011 (code 530 11SYN\_2\_1265).

**Conflicts of Interest:** The authors declare no conflict of interest.
