Ristretto and Fermented Tea are produced all around the globe. And they change according to region in where they are cultivated. So, the question arises what is Ristretto and Fermented Tea's differentiating factor?In following section we will take a close look at what is Ristretto and Fermented Tea color, serving style, types and much more. First thing to know is what are the different types of Ristretto and Fermented Tea. Well, Ristretto types include L'autentico, vanilla while types of Fermented Tea are Oolong, Black, Pu-erh.