The first condensate is the head, and it contains undesirable components. The last condensate is the feints and it is also undesirable, although it adds flavor. In between is the heart and this forms the desired product.
The first part of a process is the head, which contains unwanted elements. The last stage is the feints, which are also undesirable but contribute to the overall taste.  The middle portion is the heart, which produces the desired outcome.