This fraction is the first part of the distillate collected. A major component of this fraction is acetone, or nail polish remover. But there are other compounds in there as well. In my experience, often the very first drops of foreshots, that can start slowly coming over from around 40°-45°C (104°-113°F, have a wonderful, rich, sweet smell, but you really don't want to be drinking this stuff (headache city :lol: ).
On a pot still, the absolute minimum that should be allocated to foreshots is 150ml per 25l of wash. So, for a spirit run of, say, 3 stripped 25l washes (with no cuts made in the stripping run), you would want to discard 450ml of foreshots. This fraction should never be recycled, or used in any way for beverages, but it does have some uses. It's a great solvent, can be saved for cleaning runs of new stilling equipment, and is great for starting charcoal BBQs. Use it around the house / shed in place of methylated spirits (denatured alcohol).
In my still charged with 40% low wines, this fraction reads about 82% on the alcoholmeter / alcometer)