In the process of wine production, every single element holds its value. Each procedure, from tilling the soil to storage, plays a role in preserving the quality of wine. However, special attention should be given to wine corks. For over 400 years, cork stoppers have been used for sealing wine bottles. Due to their softness, ability to prevent gas and air permeation, and resistance to decay and fire, they are indispensable in wine production. What was crucial in the production and design of wine corks was preventing wine oxidation. The best corks, which facilitate proper aging, allow only 3.5 ounces of oxygen to pass through annually.
A glimpse into history
Around 3000 BCE, Egypt became a center for wine production. Egyptians perfected the craft of sealing amphorae using organic materials such as leaves, reeds, as well as pieces of ceramics and clay to create hermetic seals. It was in the 4th century BC that cork was discovered as a material for making fishing floats. At that time, they likely did not anticipate that centuries later, corks would become crucial for preserving wine quality. The earliest evidence of wine corks was found in the wrecks of Roman ships from the 5th century BCE. However, corks were not commonly used as wine closures at that time. After the fall of the Roman Empire, trade declined, along with the use of corks. It wasn’t until the 17th century that corks returned to the scene, becoming the dominant closure for wine bottles. Its presence in the wine world for nearly four centuries was unquestionable. However, in the 1970s, alternative closures emerged, challenging the cork monopoly. Despite these changes, millions of winemakers and wine enthusiasts remained faithful to cork. The issue of cork taint became pronounced in the 1980s. Political upheavals in Portugal in 1974 led to a decline in cork production quality. The use of inadequate fertilizers and insecticides worsened the problem. Demand for corks increased, but quality control was weak. By the late 1980s, heightened awareness of TCA led to the development of alternative closures, triggering changes in the cork industry. Today, there is a noticeable trust in cork wine closures, which preserve quality and offer the best solution for its preservation. In 1956, 20 bottles of wine from 1789 were found with corks in good condition. This discovery testifies to the longevity and effectiveness of cork closures.
Types of wine corks
There are various types of closures. Natural, plastic, technical, and other closures like screw caps. Synthetic corks regulate oxygen flow, while some natural corks allow for easy opening and closing.
Natural Corks
Natural corks are an environmentally sustainable choice for wine closures. They are made from cork oak bark, carefully harvested. There are different categories of natural corks. They can be one-piece, cut from a single piece of bark, or multi-piece, consisting of at least two joined parts.
Synthetic Corks for Wine
Synthetic corks are a newer addition to the wine industry, often made from petroleum-based plastics, though some manufacturers experiment with plant polymers. They allow for precise control of oxygen transmission, beneficial for scientifically based wine production processes.
Champagne Corks
Champagne corks must withstand the high pressure created by bubbles. They are usually made from high-quality compressed cork to ensure safety and preserve sparkling wine.
Screw Caps
Screw caps, first adopted by wineries in Australia in the 1950s, are now popular worldwide as an economical alternative to corks. While effective, this solution is not recommended for preserving wine quality.
Technical Corks
Technical corks, made from cork pieces or granules combined with adhesive, provide a sustainable solution for wines that do not require long aging. They are ideal for wines with a short shelf life.
Glass Closures
Glass closures, known as Vinolok, function like corks but are made of glass. They use a rubber or plastic seal to prevent air entry and are aesthetically pleasing, keeping wine clean and untouched.
Crown Caps
Crown caps, often made of metal, are used during fermentation or wine aging. After this process, they are replaced with conventional wine corks. Different types of wine closures significantly influence the longevity and quality of wine. High-quality closures help preserve freshness and wine quality, providing winemakers with the best options for their products.
