Wheeler Patents a Method for Roasting Malt

On March 28, 1817, London chemist and manufacturer Daniel Wheeler received British Patent No. 4112 for a “new or improved method of drying and preparation of malt.” His process heated malt to approximately 400 degrees Fahrenheit in a rotating iron cylinder. Keeping the vessel in motion allowed the grain to become extremely dark while reducing the risk of uneven burning or charring. The resulting black patent malt gave brewers a powerful source of color and roasted flavor that was legally still malt. This was particularly important after British legislation restricted the materials that brewers could use to color beer. Porter brewers could combine a large proportion of efficient pale malt with a small quantity of patent malt to produce dark beer, while Irish breweries later used the ingredient in developing the character associated with stout. Wheeler’s invention therefore became an important link between industrial malting technology and the changing production of porter and stout.