The humble crown cap
Crown caps have become the closure of choice for glass beer bottles around the world.
Before the invention of crown caps, the average life of beer was short as often sealed with corks, which lacked reliability and often had leaks of both liquids and gases ( both in and out). In 1892, the crown cap was patented by William Painter, and it revolutionised the beer industry. William Painter was an Irish American mechanical engineer and worked with manufacturers to develop a universal neck for all glass bottles. After registering the patent, William Painter founded the Crown Cork and Seal Company, in Baltimore USA.
Inexpensive to produce, it was composed of metal with a knurled end in the form of an inverted crown (hence the name crown cap). To prevent any leakage of liquid, the cap was covered with a thin cork disc and a film sealing the contents of the bottle. This was to avoid the direct contact between liquid and the metal which could have affected the purity and taste of the beer. The reliability of the seal allowed breweries to distribute beer over longer distances due to its extended shelf life.
The cork crown cap quickly became the preferred sealing method due to its reliability and ability to preserve the freshness and carbonation of beer. However, with prohibition in USA in the 1920s, the focus of the crown cap was shifted to carbonated soft drinks.
With the end of prohibition, came the wide use of crown caps across the wide drinks market including wine espresso for secondary fermentation of champagne and sparkling wine with modification by bidules and other inserts to catch the lees instead of the older cork and agrafe staple.
In the early 20th century, crown caps were primarily made of tinplate, a form of steel coated with tin to prevent rusting. However, by the mid-20th century, manufacturers began using more durable materials like aluminium and stainless steel. For cider we use stainless steel due to the magic acid in cider corroding the ordinary steel and turning the cider black!
It originally had 24 teeth, along with a cork seal. Since then the cork disc has been replaced with PVC material and the cap height has been shortened. In the 1930s, testing determined the optimal number of teeth to be 21 and that is now standard, 24 made the cap too tight and difficult to open.
The crown cap provides more than just a secure seal for breweries, but also a unique branding opportunity. By customising design, colour, and logo, companies can establish their brand identity to help increase visibility and brand recognition.
Despite the rise of alternative closures like aluminium screw caps and plastic caps, crown caps remain popular due to their cost-effectiveness and proven reliability.
Despite being an excellent seal and used for secondary fermentation closure for many months and years, champagne houses have been reluctant to use it for their finished product citing “But who wants to open a bottle of champagne with a beer opener?” Champagne houses rely on the glossy image. They were slow to adopt the RotoJolly too ( see seperate article). However some sparkling winemaker first in South Africa have started using the crown cap as a closure. And , modern Method Traditional bubbly, from the Loire Valley to California, now use the crown cap more and more. One champagne house tried but was blocked in the most French of ways! It was ruled illegal by the authorities since the rules says that the text “Champagne” must be printed on the cork and since there is no surface suitable for printing on this closure it was not following the rules… see link
TeePee Cider will launch a 375 cL bottle with a crown cap closure in the new future. Watch this space.