To dunk or to dip a biscuit or some other food, usually baked goods, means to submerge it into a drink, especially tea, coffee, or milk. Dunking releases more flavour from confections by dissolving the sugars, while also softening their texture. Dunking can be used to melt chocolate on biscuits to create a richer flavour. Dunking is a popular way of enjoying biscuits in many countries. A popular form of dunking in Australia is the "Tim Tam Slam", also known as 'tea sucking'. The physics of dunking is driven by the porosity of the biscuit and the surface tension of the beverage. A biscuit is porous and, when dunked, capillary action draws the liquid into the interstices between the crumbs. Dunking is first reported with ancient Romans softening their hard unleavened wafers in wine. Modern day dunking has its roots in naval history when, in the 16th century, biscuits known as "hard tack" were on boardRoyal Navy ships, which were so hard that the British sailors would dunk them in beer in order to soften them up. The most popular biscuit to dunk in tea in the United Kingdom is McVitie'schocolate digestive. In the US, Oreos are frequently dunked in milk, while the Dunkin' Donuts franchise is named for the practice of dunking doughnuts into coffee. In South Africa and in India, rusks are a popular food for dunking in both tea and coffee. In the Netherlands, stroopwafels are commonly dunked in tea or coffee, often after having been set on above the hot drink for a few minutes to melt the caramel inside. In Nigeria, bread is commonly dunked in tea or coffee, while Acarajé is dunked in pap. In New Zealand gingernut biscuits are commonly dunked in tea or coffee. Dunking is also used as a slang term for intinction: the Eucharistic practice of partly dipping the consecrated bread, or host, into the consecrated wine, by the officiant before distributing.
Etiquette and style
While modern day dunking has its origins in 16th century naval history, it wasn't until the 19th century and the emergence of afternoon tea in the early Victorian era that Great Britain and Ireland began to regard biscuits as something to be dunked in tea; a British and Irish custom that was later exported around the globe. Different cultures have different attitudes toward biscuit dunking. Historically in British high society, dunking was frowned upon and generally seen as children's or working class fashion. However, Queen Victoria herself was said to enjoy dunking her biscuits, a German custom from her younger days. In 2007, a tea room in Brighton, England, banned dunking on its premises.
Science
Physicist Len Fisher of the University of Bristol presented some light-hearted discussion of dunking on "National Biscuit Dunking Day" in the UK, as part of an attempt to make physics accessible. Fisher appeared to be somewhat taken aback by the large amount of media attention, ascribing it to a "hunger for accessible science". Fisher also described his astonishment at journalists' interest in one equation used in the field: Washburn's equation, which describes capillary flow in porous materials. Writing in Nature, he says "the equation was published in almost every major UK newspaper. The journalists who published it took great care to get it right, some telephoning several times to check". In 2012, Michelin starred English restaurateur Heston Blumenthal researched the effect of dunking chocolate biscuits, and concluded that it improved the biscuit's aroma. "If you have chocolate on one side, if it melts a bit, you get a velvety smooth texture and then the delicious flavour as a result."
Cultural references
In Marcel Proust's novel In Search of Lost Time, one of the narrator's childhood memories sets in while tasting a madeleine dunked in tea. The soft, spongy consistency of the madeleine could seem like an odd choice as dunking is more common with crisp baked products, such as biscuits. In fact, draft versions of Proust's manuscript reveal that the author initially had the narrator dunk a piece of toasted bread. In the British comedy-drama filmThe Best Exotic Marigold Hotel, Evelyn Greenslade, one of the main characters, explains dunking to her new employer during an interview whilst drinking Builder's tea. Evelyn describes it as "lowering the biscuit into the tea and letting it soak in there and trying to calculate the exact moment before the biscuit dissolves, when you whip it up into your mouth and enjoy the blissful union of biscuits and tea combined." In It Happened One Night, a 1934 American romantic comedy film with elements of screwball comedy directed and co-produced by Frank Capra, in collaboration with Harry Cohn, in which a pampered socialite tries to get out from under her father's thumb and falls in love with a roguish reporter, the reporter teaches her the proper way to dunk a doughnut at a diner. As an heiress who normally dines in elegant hotels, she is unfamiliar with the cultural practices of everyday people.
