OK so I think you are trying to make Turkish Beyaz Peynir / White Cheese which is a feta like brine preserved cheese. Here's one recipe
and a second here
. Feta normally uses mesophilic culture, for Beyaz Peynir it looks like you use both. In your recipe after you cut the curds do you heat the milk and if so to what temp?
Also, historically these types are goat's milk cheeses, for Feta, if using cow's milk then you need to add some lipase
to give it that piquant taste. Have a look at some of the Feta making records in the Brine Preserved Cheese Board.
OK, the key issue of no curd set. Everything I could think of looks good. It's possible the milk has something in it that is causing the problem, suggest try another brand just in case, also it's not ultra-pasteurized or ultra heat treated long life is it?
The main area I can think of is the rennet. From their website, it looks like Mayasan is a cheese ingredients distributor and from your link you got Valiren Brand liquid rennet correct? Valiren is/was made by US based Valley Research Inc.
and it is a Rhizomucor miehei (Mucor miehei) microbial fungal based rennet which is fine. Looks like Valley Research was bought out in July 2008
by huge Danish DSM company.
Rennet is normally recommended to be diluted at 40 to 1 for single strength, you have 4 tablespoons to 1 teaspoon, a ratio of 12 to 1. Next time recommend use more water.
Also, this book says
that rennet should immediately be added to the milk once diluted as it becomes unstable when diluted and loses strength. Next time don't try pre-preparing.
I stir my rennet in for 60 seconds, maybe try longer next time.
Do you know how it was stored before you bought it and currently stored? Liquid rennet should be stored in an opaque container as it degrades from UV light, and at refrigerator temperatures, higher prolonged temperatures will result in strength loss. It also becomes weaker if foamed/shaken.
Next batch when you add correct amount of starter culture that will lower the pH which also helps rennet to get a good curd set.
Lastly, while I assume you followed your rennet's package directions on amount, I'd up the amount to maybe 50% more and if want do a smaller test batch.
Hope helps, anyone else have ideas?