Beer foam carries aroma compounds that make beer smell fruity and sweet. A special machine was made to measure these compounds in beer before and after foaming. Some compounds, like ethyl hexanoate and ethyl octanoate, are released more after foaming, giving beer its aroma. The more hydrophobic a compound is, the more likely it is to be in the foam. This means that certain compounds move to the foam during foaming and are released more when bubbles burst. Beer foam helps release specific aromas, making beer smell delicious.