I am writing in regards to Bulgarian White cheese Sirene. My wife Ivanina is from Bulgaria and I have a great passion for cooking. I have recently been trying to make a traditional Sirene at home and I am looking for the correct type of culture or rennet to add to the cheese. I am familiar with the yoghurt and the bacteria "Bacillus Bulgaricus" that makes it so special, but I am having trouble finding the correct recipe to make the cheese. I would like it to be as authentic as possible, but I know that there is no way to replace her grandmothers homemade cheese. I hope you can help. Thank you. Chao.