What is the portion of the second distillation that is kept and sold known as?

The portion of the second distillation that is kept and sold is known as the heart. During the distillation process, the spirit is separated into different fractions: the heads, hearts, and tails. The hearts are the middle fraction, which contains the desirable compounds that contribute to the flavor and quality of the spirit. This is the portion that distillers aim to collect and is typically what is bottled and sold.

The heads, which are collected first, often contain volatile substances that can impart undesirable flavors, while the tails, collected last, contain heavier compounds that are typically not suitable for drinking. Thus, the heart is the ideal part of the distillation process and is emphasized in distilling practices because it is where the best flavors and aromatic compounds reside.