There are three main theories on the churning of cream into butter, viz.: 1. Fisher and Hooker’s Phase-Reversal Theory 2. Rahn’s Foam Theory 3. King’s Modern Theory. 1. Fisher and Hooker’s Phase-Reversal Theory (1917): According to this theory, churning is a process of phase reversal, i.e., changing an oil-in-water type emulsion (such as cream) to […]