Sel Sanayi A.Ş. The Milan study is the third peer-reviewed publication on Sel Sanayi’s collagen products in two years. Those studies suggest that CollaSel Tripeptide may stand out from typical collagen products because of its much smaller molecular size. ...Collagen has only been widely known as a supplement for around a decade, but Sel Sanayi has been in business much longer. For Tezman, the broader shift underway in the ingredients industry is not a passing trend but a durable structural change.