closures are the devices that keep liquid in bottles and oxygen out of them. The great historical virtue of alcoholic beverages is their relative stability, enabling distant and even global commerce, although that stability is reliant on strictly controlling the amount of oxygen to which they are exposed. Long distance transportation relies upon containers matched with particular closures. Whether the answer is amphorae sealed with wooden plugs coated with pine tar, hardwood barrels with softwood bungs, hand-blown glass bottles and corks, or machine-extruded bottles with uniform aluminum screw caps and beyond, the closure still represents the point of greatest vulnerability in the system for transporting spirits.
The ancient Mediterranean use of wood plugs covered in pitch or resin, sometimes supplemented by oil-soaked cloths, is reflected in the continued consumption of retsina, a Greek wine that contains a tiny amount of pine tree resin, and in mastika, a Mediterranean spirit that utilizes the resin of the eponymous tree for its aromas and flavors. In the pioneering South Asian spirits trade, as the circumnavigator William Dampier observed in 1697, the earthenware jars used were similarly fitted with wooden stoppers that were sealed with treated paper and then covered with clay. See
The handblown glass bottles that came into increasing use in the seventeenth century (for transporting small amounts of spirits and storing them for ready use) were made with slightly flared necks that could be sealed with plugs made from the spongy bark of the cork oak (Quercus suber). This was not a new method; corks date back to antiquity, and indeed many of those amphora-sealing wooden plugs were cork bark, but it had fallen out of use, as had the glass bottle itself. With the increasing trade ushered in by the early modern period, the advantages of both were rediscovered. Cork was, as Walter Riley noted in 1906, “light and impermeable to gases and liquids, elastic, and without taste and smell.”
That elasticity was essential, since there was as yet no way to make bottles of precisely uniform dimensions, and the cork had to be able to adjust to the bottle’s neck. This often left a little play in the fit, and corks needed to be tied down or dipped in wax to ensure that they stayed put. Only in the late nineteenth century did it become possible to achieve true uniformity of both bottle and cork.
The ability to make perfectly cylindrical bottlenecks and uniform, machine-cut corks meant that a slightly tapered cork with an end a bit wider than the bottle’s neck could be squeezed in a press until it could be inserted into the bottle wide-side first, whereupon it would expand to grip the sides of the neck tightly but still be extractable with a corkscrew. This system, now associated with wine, was adopted for spirits as well, and it continues to be found with a few old-school European bottlings.
But unlike wine or beer bottles, spirits bottles had to be resealable, at least in most countries (there are those where it is considered bad form to not discard the closure and empty the bottle once it is opened, but they are the minority). Corks can be difficult to reinsert and are often damaged by the act of extracting them. A traditional solution was the ground glass stopper, where the end that fit into the bottle had to be machined to fit each individual one. This was of course expensive. By the middle of the nineteenth century, it was largely supplanted by the “shell cork and stopper” closure, where a cork was drilled out and fitted permanently into the bottle and a tapered glass stopper pressed into the opening.
At the same time, advances in bottle molding made it possible to use screw caps. These too were not entirely new—as early as the sixteenth century, some bottles were fitted with threaded pewter neck bands and screw caps, but these had to be custom-fitted to each bottle. Samuel A. Whitney’s 1861 US patent for an internally threaded bottleneck and a glass stopper with rubber gasket ushered in a new era of cheap, effective closures. Indeed, the transition from merchant bottling to distillery bottling that came in the late nineteenth century would not have been possible without such things. See spirits trade, history of.
New closures introduced at the time included non-resealable but very cheap crown caps, still used for spirits in some countries, resealable swing-top “lightning” stoppers (patented by Charles de Quillfeldt in 1874), and externally threaded bottlenecks with caps that screwed down over them. These last would become the industry standard, in metal or, later, in plastic, for all but luxury brands, which would continue to use cork stoppers, perhaps with the hope that such stoppers suggest higher-quality brands, as they have traditionally done for wine (the type most favored is the so-called T-top, where a short cork is glued to a wooden, plastic, or metal knob that enables the cork to be pulled from the bottle).
For some premium brands, however, the risk of counterfeiting trumps the risk of seeming low-class. For them, there is the nonrefillable closure, patented as far back as 1898 and in use since at least 1912, when Johnnie Walker used it. See Johnnie Walker. This type of closure was perfected by Earl Unger for Seagram’s in 1971, who used a clever arrangement of barriers and a ball valve to ensure that the bottle can be poured from, but not into (Unger’s patent drawing featured a Chivas Regal bottle). See Chivas Regal and Seagram Company Ltd. A simpler version also in use features a tamper-evident plastic insert that the cap screws onto that cannot be replaced without breaking the bottle.
The T-top itself has seen changes in recent years as well. With an increased awareness of TCA contamination, natural cork is seen as inconsistent, and while incidents of corked spirits are less common than of corked wine, contrary to popular supposition they do occur. In recent years, the cork in T-tops has been at least partially supplanted by plastic and synthetics or the closures replaced by glass stoppers with silicon gaskets or even the humble screwcap (most often aluminum Stelvin closures, where the top is part of a capsule that fits over the neck). As screwcaps become the norm for everyday wines, and as agglomerated corks and sterilized (TCA-free) corks are becoming the norm in more expensive wines, the adoption of alternative closures in spirits can be expected to continue.
bottles, labeling, and packaging; and TCA (2, 4, 6-trichloroanisole).Dampier, William. A New Voyage round the World. London: 1697.
Jeffrey, David W., Gavin Sacks, and Andrew Waterhouse. Understanding Wine Chemistry. Chichester, UK: Wiley, 2016.
Jackson, Ronald. Wine Science: Principles and Applications, 4th ed. San Diego: Academic Press Elsevier, 2014.
Lindsey, Bill. “Types of Bottle Closures.” Bureau of Land Management/Society of Historical Archeology Historic Glass Bottle Identification and Information Website. https://sha.org/bottle/closures.htm (accessed March 15, 2021).
Riley, Walter A. “The History and Use of Corks and Other Stoppers.” Journal of the Institute of Brewing 12 (1906): 172–207.
By: Doug Frost and David Wondrich