Goat cheese (Feta) with a colony of "ropy" lactic acid streptococci. This bacterial starter culture and a proteolytic enzyme such as rennet (chymosine) are used to coagulate the milk being used for the cheese. Most of the water present in the milk is strained away from the protein curd in the form of whey. The protein (mostly casein) is then ripened to obtain the proper structure and flavor of the cheese.