What are raw alpha acids described as?

Raw alpha acids are described as non-isomerized and water insoluble. In their natural state, alpha acids are found in hop resin and primarily consist of several compounds, such as humulone. These compounds have not undergone isomerization, which is the process that occurs during the boiling of hops, where alpha acids convert into iso-alpha acids that exhibit bittering properties in beer.

Due to their non-isomerized state, raw alpha acids do not dissolve in water, which is a significant characteristic. This insolubility means they do not impart bitterness until they are heated and isomerized during the brewing process. The other options cover properties that raw alpha acids do not possess, failing to accurately describe their characteristics. For example, raw alpha acids are not chemically altered or volatile, nor are they fully isomerized or soluble in water. Understanding the nature of raw alpha acids is essential for grasping the bitterness mechanism in brewing.