Corks and their preparation for bottling

How to prepare your corks for bottling:

1. If you are using a high-quality floor corker there is no need to soak or sulfite any corks. Simply insert them dry. (NB: see note about dry corks below) However, a quick dip in sulphite solution and an equally quick rinse is OK also.
2. If you have difficulty inserting long corks, give them a quick dip or rinse in sulphite (NOT PINK CHLORINATED) solution and then put them in warm water while you are bottling. This is usually sufficient to ensure smooth insertion.
3. If you are using a small, hand-held corker (single or double-lever types) you may need to prepare your corks by rinsing them in Sulphite solution, then soaking them in warm water for up to 15 minutes (5 minutes is often enough for short corks). If you have trouble getting corks to pass through your hand-held corker, you may want to try adding ½ cup of glycerin to every four liters of warm water that you use for soaking. This ensures that the corks get enough moisture to lubricate their passage through the corker, but they won't be over soaked and crumble.

While some books talk about boiling and long soaking in sulfite solutions, these are very bad ideas. Cork is tree bark, and boiling it turns it to mush. Mush won't seal your bottles. Long soaking does the same thing. Once you have opened a bag of corks, you may need to take special care of the unused corks.

DRY CORKS

The trouble with handling very dry corks is that it's tough to judge how long you can soak them before they become mushy. However, there is a nifty technique that you can take advantage of, if your corks are brittle either from age or low humidity storage. This is also a convenient way to store any excess corks that you may have, and you will always be ready to cork. You can construct a 'cork humidor'.

You will need a sanitized plastic bucket and lid, an empty wine bottle, and a 1.25% solution of metabisulphite (eight teaspoons of metabisulphite powder dissolved in a gallon of cool water). Fill the wine bottle halfway with the solution, and carefully stand it up in the bottom of the bucket. Gently pour your corks into the bucket, filling the space around the bottle, and put the lid on tightly. Leave the bucket in a room temperature area for about a week. In that time the liquid evaporating from the wine bottle will raise the humidity in the bucket in turn raising the humidity in the corks, making them pliant enough for easy insertion. The sulfur dioxide gas coming off the liquid will prevent the growth of moulds or spoilage organisms, keeping the corks sanitary. No further treatment of the corks will be necessary before bottling.

If you want to store your corks this way, replace the solution in the bottle every four weeks, and keep the lid tightly sealed. That way your corks will always be ready for use. We currently stock several grades or types of corks for the amateur winemaker:

LONG TERM STORAGE CORKS:

1. Synthetic #9 long Corks (5+ years)

• One of the latest developments in corking. No off-tastes.
• Do not dry out.
• Sterilize, rinse & cork. Floor corker recommended. NO SOAKING NECESSARY.
• Can be stored in any position immediately – upright or lying down.
• Sold in bags of 90 & 1000.

2. Double Disc Winery Grade long Corks (Up to 5 years or more)

• Cut from the best bark of the cork tree.
• Sterilize in sulphite solution, rinse & cork. Floor corker recommended. Dry insertion or minimal soaking time.

• Store for 3 - 5 days upright after corking, then lay down.
• Sold in bags of 30, 90 & 1000.

3. Natural Cork (2 – 3 years)

• Sterilize in sulphite solution, soak in warm water for 5 – 15 minutes
• Floor corker recommended. Dry insertion or minimal soaking time.
• Store for 3 - 5 days upright after corking, then lay down
• Sold in bags of 30, 90 & 1000

4. Agglomerate #9 Long Corks (2 – 3 years)

• Sterilize in sulphite solution, soak in warm water for 5 – 15 minutes
• Floor corker recommended. Dry insertion or minimal soaking time.
• Store for 3 - 5 days upright after corking, then lay down
• Sold in bags of 30, 90, 1000

SHORT TERM STORAGE CORKS:

5. Agglomerate #9 Short Corks (Up to 15 – 18 months)

• Dry insertion or minimal soaking time.
• Sterilize in sulphite solution, soak in warm water for 5 – 15 minutes
• Store for 3 - 5 days upright after corking, then lay down
• Sold in bags of 30, 90, 1000