Back around 1700, the typical wineglass had a capacity of just 66 milliliters (a little over two ounces). Typical capacities increased gradually throughout the following centuries, but starting around 1990 the average size ballooned dramatically, reaching 449 ml, over 15 ounces, and well over half the size of a typical 750 ml bottle of wine.
According to the study, glass sizes were initially kept small because of a glass excise tax in England that was abolished in 1845. In the 20th century, “wine glasses started to be tailored in shape and size for different wine varieties,” according to the study, “both reflecting and contributing to a burgeoning market for wine appreciation, where larger glasses were considered important.”
Studies have also shown that larger glass sizes have boosted wine sales in bars and restaurants, giving those establishments an incentive to go big. The sight of big glasses in restaurants may in turn help shape norms about typical glass sizes when drinking at home.
Recent years have also seen the introduction of cartoonishly large wineglasses capable of holding a full 750ml bottle. While some of these are no doubt purchased as novelty items, large numbers of product reviews on sites such as Amazon suggest that some people, at least, are using them for their intended purpose.
“It truly is a gift to have the ability to drink an entire bottle of wine without refilling the glass,” one reviewer wrote earlier this year.
The paper notes that while the growth in glass capacity coincided with an increase in wine-drinking in England, they can't establish a causal link between the two. However, they say it seems plausible that “a larger cup or glass increases the amount of beverage poured and, in turn, the amount drunk.”
Finally, people don't typically fill their wineglasses to capacity, so an average capacity of 449 ml doesn't indicate that the average wine drinker is gulping down over half a bottle per glass.
“I . . . hope the authors have not been committing the faux pas of filling [their glasses] to the brim,” writes Basil F. Moss of the Royal Derbyshire Hospital in a response to the study. “They should usually be filled to the widest point, which leaving the glass about a third full — the shape of the glass can then capture the aroma. Cheers!”