Preparation of beverages containing a head of froth

摘要

Beverages such as beer in a sealed conventional bottle or can for individual consumption are provided with a head of froth after the can or bottle is opened by subjecting the beverage to an excitation treatment that causes gases dissolved in the beverage to come out of solution and form a head of froth having small uniform bubbles throughout. The gases dissolved in the beverage are carbon dioxide and nitrogen in amounts of 0.8 to 1.8 vols./vol. and 0.015 to 0.035 vols./vol., respectively. Excitation is performed by injecting liquid and/or foam into the beverage or by passing the beverage through a bed of small discrete sharp edge polystyrene granules.