Hello! I have been making feta cheese at home for almost a year now and I am having a problem which I do not know how to deal with. The cheese spends about 1-2 days being pressed in the refrigerator before I brine it, so that the liquids run out. During this time, it starts developing some sort of a bitter taste which becomes more intense if it spends even more time away from the brine. I have assumed that this bitter taste indicates bacteria growth but I have no scientific basis or any expert opinion on this. Would anyone know anything about it?
I also add a few drops of calcium chloride to the milk during the cheese-making process according to the instructions of the recipe I am following (I don't know how necessary it really is though). I mention that, because I know that the liquid calcium chloride that I use has a very bitter taste. Could the bitterness come from it?
All I use is vat-pasteurized store-bought milk, liquid animal rennet, a powdered mild lipase, calcium chloride, a tbsp of home-made yogurt (per 1.5 gal milk) and salt. I also have read online that too much cheese culture, might increase the acidity of the cheese. Could the rennet or lipase have anything to do with it?
So, would the bitterness come from bacteria growth, calcium chloride, too much culture in the cheese, or something else I have not considered yet?
Also: I would like to start flavoring this cheese with herbs and other types of foods, but I do not know how, and where to look for information. Can anyone suggest me anything as a starting point, or at least tell me where to look for more information about such techniques?