Bentonite is a type of clay used in winemaking as a clarifying agent. It’s added to wine to remove proteins that can cause haziness, thus ensuring the wine remains clear when chilled or aged. Bentonite works by binding to the proteins, forming larger particles that are easier to remove. This process is especially important in white wines and rosés, which are expected to have a clear appearance. The use of bentonite is a common practice in both conventional and organic winemaking.