Bottling has two basic purposes:

1. Divide the Wine on different botles, in order to facilitate its transportation and storage in good conservation conditions;

2. Allow a maturation period in bottled wine, and consequently creating added value.

Basic rules for bottling, transporting, and storing wine.

These basic rules should be followed:

- The correct selection of the right size and grade of the cork closure to suit the size, bottle, and wine type;

- Correct storage of the cork closure before bottling;

- Best practice in the bottling, transportation, and storage of wine is of extreme importance if wine is to be delivered to the consumer in optimum condition.

Selecting a cork closure:

- The corks to be used must be chosen bearing in mind the bottling dimension of the bottleneck, as well as the type of wine and its length of maturation.

- For the majority of wines, the diameter of the natural cork stopper should be at least 6 mm larger than the diameter of the internal bottleneck. For prolonged maturation periods, a diameter superior to 6 mm is advisable, but should not exceed 8 mm.

- Wines of long maturation may be sealed with longer and wider diameter cork closures. If a longer cork closure is used, it is necessary to always respect the headspace between the bottom of the cork and the surface of the wine (the vacuity). Normally the vacuity should be a minimum of 15 mm.

Storage of cork closures:

- Whenever possible, the cork closures should be used soon after delivery. Long storage periods should always be avoided. The advisable maximum period of storage is six months, in correct storage conditions.

- The polythene bags holding the cork closures should only be opened upon use. In general, the corks are sealed in gas barrier bags, sanitized with SO2 (sulfur dioxide). This gas acts simultaneously as an antiseptic preservative and an antioxidant, thus protecting the cork.

Correct storage conditions for cork closures:

- In-ventilated and dry places with a mild and stable temperature between 15 oC (59F) and 20 oC (68F) and a relative humidity level between 40% and 70%

Bottling, transportation, and wine storage:

- By taking advantage of cork’s compressibility, the bottling machine should gently compress the cork closure and gently insert it into the bottleneck.

- The correct compression is 2 mm less than the diameter of the bottleneck. A cork closure with a diameter of 24 mm should be compressed to 16.5 mm for it to correctly enter an 18.5 mm diameter bottleneck .

- Cork closure compression must never be greater than 33% of its diameter or this can damage cork’s internal structure, compromising its elasticity and consequently the correct bottle sealing ability. Hence, for a cork closure with a diameter of 24 mm, the maximum compression is 8 mm.

- Due to its elasticity, cork recovers its volume within the first five to 10 minutes after it has been bottled, adapting itself to the irregularities of the bottleneck and exerting a uniform force throughout the glass surface. Therefore bottles should remain vertical and should not be laid in a horizontal position immediately after corking.

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