－11－Insights from our Toyama Cellar: Cautions on corks and screw caps.※ At Village Cellars, in our wine listings we add ‘S’ between the product name and the vintage year to indicate bottles with screw caps.〈How to open a screw cap bottle〉1. Grasp the bottom of the bottle with your right hand.2. Hold the entire bottleneck (neck) with your left hand.3. With your right hand, rotate the bottom of the bottle so that your thumb is pointing towards you.When you hear a clicking sound and the perforations are cut, remove the cap.◆Right-handed◆ Left-handed1. Hold the bottom of the bottle rmly with your left hand.2. Hold the entire bottleneck with your right hand.3. With your left hand, rotate the bottom of the bottle so that your thumb is pointing away from you. When you hear a clicking sound and the perforations are cut, remove the cap.* Please turn the hand holding the bottom of the bottle, not the neck. A few months ago we were contacted by a person who had badly cut their hand while opening a bottle of wine. He had tried to cut the foil around the stopper to open his wine, but it was so stiff the blade slipped and he cut himself. He hadn’t realised that he was opening a screw cap, and was using a traditional foil cutter for cork enclosures on the bottle.The problem is there are two different types of screw caps. While you can recognise a standard screw cap at a glance, (left photo), the smooth screw cap (right photo) has a smooth surface with the screw thread on the inside, and is therefore more difficult to distinguish. This smooth cap is used by wine producers who adopted them for their ‘smart style’ as they transitioned from corks to screw caps, to give their bottles a more elegant look.◆ Why screw caps (the problem with cork)?Light, elastic, and tough, cork is a natural material that cannot be replaced by plastic, and has been used as a wine stopper for almost 400 years. However, in recent decades, as the quality and quantity of wine has increased along with the evolution of knowledge and techniques for viticulture and winemaking, winemakers began paying more attention to two major problems associated with cork stoppers ̶ ‘random oxidation’ and ‘cork odour’. Random oxidation (also known as sporadic oxidation) is the early oxidation of bottled wine while waiting for them to age. In a box of 12 white wines, the wines will oxidize to varying degrees, showing colours from normal through to heavily brown. At one time, we discarded up to 30% of the wine after it was aged and stored for several years in our constant temperature warehouse because of random oxidation. Another problem, corked wines or cork taint, is caused by 2,4,6-Trichloroanisole, also known as TCA. A product of mould reacting with chlorinated phenols (sterilising agents), TCA doesn’t harm the human body, but even a trace amount gives off a unique musty odour.While cork makers at the time were initially reluctant to admit the TCA problem was due to corks, from the year 2000 Australian and New Zealand producers looking for alternatives switched to screw caps that were already prevalent in Switzerland. “It is impossible to make wine by carefully calculating and managing it from the grower to the winemaker, and at the end of that process, entrust its fate to a small piece of wood,” said leading screw cap proponent Jeffrey Grosset.◆ The history of screw capsThe screw cap was originally invented in the 1850s to seal glass containers, and has been used for whisky bottles since the 1920s. In the 1930s, UC Davis in California repeatedly tested its use with wines. A variety of screw caps were developed in the 1950s, and the ‘Stelcap’ name registered as a trademark by a French manufacturer. In 1968, after the quality of Stelcap was proved in comparison tests with premium corks, France officially approved the use of Stelcap for wines, and trials were carried out with prestige wines including Château Au Brion. An Australian company acquired domestic manufacturing rights for Stelcap in 1970. In addition to work at the Australia Wine Research Institute (AWRI), R&D was carried out by several major wine producers from 1973-1976, resulting in the development of the ‘Stelvin’ screw cap. In 1976, the major winery Yalumba introduced a wine on market using this screw cap. However, it was a failure, not because of performance problems, but due to market resistance to their appearance. Château Au Brion also discontinued its project in 1979 because of a problem with the liner under the screw cap. On the other hand, in Switzerland, the world’s first wine under screw cap was released in 1972, and the number of screw caps in use increased rapidly to 10 million in 1990 and 60 million in 1996. In 2000, Clare Valley winemakers led by Jeffrey Grosset of Grosset Wines also adopted screw caps. New Zealand soon followed, and for a while the production of screw caps couldn’t keep up with demand.◆ The advantages of screw capsThe advantages of the screw cap are (1): avoiding the random oxidation mentioned above; (2): avoiding the risk of TCA; (3): not affected by humidity; (4): preventing cork from affecting the flavour of the wine; (5): both white and red wine age safely; (6): can be stored for a long time with no recorking required; (7): no odour in the cellar; and (8): an important advantage is that bottles can be opened and closed easily.The impact of screw caps is said to be greater in avoiding random oxidation(1) than TCA (2). With regard to aging (5), at Village Cellars we confirmed the quality of aging under screw cap for ourselves. When Grosset first produced wines under screw cap, we bought and stored several sets of the same vintages under both cork and screw cap for tasting at future seminars. The oldest sets are the Grosset 2000 Polish Hill Riesling and Watervale Riesling. At a recent comparative tasting it came down to personal preference as to which tasted better ‒ there was no question about the quality of wine aged under screw caps. Regarding (8), there is no problem closing a screw cap, but how to open it is different from the normal twisting action for opening a bottle lid, as outlined below.◆ Do not use corkscrew stickersWe thought that screw caps with a smooth surface are confusing when we heard that our staff seemed to mistake it for a cork enclosure. Even wine journalist Fumiko Aoki said she has had similar experiences. So, to prevent accidents, from the early days of screw caps Village Cellars decided to put a sticker on top of bottles with a smooth screw cap to warn against using corkscrews. This sticker is designed to stay on the bottle. If you would like to remove it, as it is water-soluble it is easy to take off using a wet cloth.