In the following:

1. SO2 means potassium or sodium metabisulphite -commonly available as campden tablets (ct) - or SO2 gas if available.
2. Gallon is used interchangeably with 5 litres (4.5 litres is more accurate).
3. Carbonate means calcium carbonate – sometimes called precipitated chalk.
4. Suss (or suss reserve) means fruit juice retained for sweetening.

Tips

• It is useful to have a variety of storage vessels of different sizes.
• Keep all bottles and vessels clean and sterile.
• Harvest grapes and crush (i.e. break the skins) and transfer the lot to a storage vessel.
• If you have either the luxury of a destalker or a very small quantity of grapes that can be destalked by hand you may prefer to destalk rather than crush.
• Kill any wild yeasts in the juice with SO2 - 1ct per gallon.
• Stand the juice overnight or for 24 hours to settle out pulp – use air lock and if possible exclude air by blanketing with CO2.
• Note this is also called ‘maceration’ and the juice extracts tannin and other chemicals from the skins, pips and stalks (the last two have more tannin and destalked grape juice will extract less tannin).
• Rack off the clearer, upper layer and transfer to the fermentation vessel(s).
• Adjust sugar and acid levels before starting fermentation.
• Add yeast; fermentation should commence within a day or two.
• If you have a lot of juice, a starter bottle is used. About 5% of the juice is transferred to a bottle which should be about 70% full. Yeast is added and the bottle is covered to exclude dirt but not air. Under this condition the yeast will grow. After a day or two when the yeast fills the juice add an air lock. When fermentation starts, the starter is returned to the main body of the juice where fermentation continues under air lock. If more than one fermentation vessel is used, divide the starter in proportion to the contents of the vessels.
• Do not fill fermentation vessels to more that 75 to 80% of capacity.
• The residual pulp layer (after racking off the settled juice for fermentation) is transferred to storage vessels; add 2 ct per gallon. Completely fill all vessels and seal with an air lock. This will eventually clear and can be used as suss to sweeten the wine after fermentation.
• When fermentation is complete and the yeast has settled, rack the wine into a storage vessel. Add SO2 - 1ct per gallon. Make sure the storage vessel is brim full and add a pinch of carbonate. Store under an air lock and leave the wine to clear.
• Store the lees (i.e. the residue after the wine has been racked off) in a separate vessel – brim full; add SO2 - 2ct per gallon – and a pinch of carbonate and store under and air lock.
• If the wine fails to clear you may need to use finings.
• If available, coarse filter the wine when it appears clear.
• Rack the suss when wine and suss are both clear.
• Blend a small trial batch of suss and wine to find the optimum sweetness. (e.g. add suss to achieve ½% sugar; if insufficient try ¾% and so on).
• Blend the wine to the preferred sugar level and sterile filter immediately.
• Fill storage vessels brim full and add SO2 - ½ct per gallon and leave to age.
• Bottle.

Important Note

If you blend wine and suss and do not have a sterile filter there is a risk of further fermentation even if only a trace of yeast it left in the blend. A wine that looks clear is not necessarily free from yeast and the only safe way to use this procedure is with a sterile filter. If you do not have a sterile filter it is safest to stick to dry wine but this may not taste as good.
If you risk sweetening without sterile filtration, add SO2 - 1ct per gallon – and a pinch of carbonate. Store the blend under an air lock and check for further fermentation. Bottle as late as possible before drinking to reduce the risk of the bottles exploding.

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