Closure

The closure protects a drink from oxygen, germs and loss of carbonation. Common types are natural cork, agglomerated cork, synthetic cork, screw cap, crown cap, swing top and glass stopper. Each has advantages and disadvantages for tightness, price, look and influence on aroma.

Natural cork lets tiny amounts of oxygen through, which can be desirable in long storage, but carries the risk of cork taint. Screw caps preserve freshness very reliably. Crown caps are standard for beer and soft drinks. The choice depends on type of drink, storage time and target group, not on quality alone.