keinokorkit

Keinokorkit are closures for wine and other bottled beverages made from polymer-based materials designed to replace natural cork while avoiding some of its drawbacks. They include monolithic synthetic corks and agglomerated or composite closures, typically produced from plastics such as polyethylene, polyurethane, or polyvinyl chloride, sometimes with additives or microcellular cores to tune permeability.

Origins and purpose: developed in the late 20th century to address cork taint (TCA), supply variability, and cost pressures. Synthetic closures provide a consistent seal and, depending on design, a predictable rate of oxygen transfer to the wine, helping winemakers standardize aging across batches.

Types and performance: monolithic synthetic corks are solid plastic closures; agglomerated variants consist of plastic granules bound together. Some designs approximate the elasticity and compression of natural cork; others emphasize rigid sealing. Advantages include resistance to cork taint, uniform dimensions, and easy removal. Limitations include differing long-term aging behavior due to oxygen transmission rates, potential consumer perceptions of quality, and compatibility with bottling lines or bottle necks.

Applications and environment: widely used in mass-market wines and beverages where consistency and cost matter. Environmental considerations vary by material and local recycling systems; some manufacturers offer recyclable options, while natural cork is often presented as a renewable alternative when harvested responsibly.

See also: cork (closure), agglomerated cork, natural cork, synthetic closures.