MAKING SPARKLING WINE
Sparkling wine is not difficult to make at home, and is well worth the time and effort involved.
The procedure involves two stages: firstly, a normal fermentation to produce a wine of no more than 10% alcohol by volume; and secondly, another fermentation in the bottle to produce the bubbles of carbon dioxide gas which give the wine its sparkle. To avoid the danger of bottles exploding during the second stage, you should follow the instructions below carefully.
The most important points to remember are:
A comparatively low alcohol level (8%-10%) from the first stage of fermentation is necessary because the Champagne yeast used in the bottle fermentation cannot tolerate much higher levels.
It is necessary to use a Champagne yeast during the bottle fermentation because it is the only yeast able to stand the gas pressure and because it will not taint the wine.
The high gas pressures generated make it absolutely essential to use only Champagne bottles, which have extra thick glass. They can be obtained from home winemaking shops or restaurants. Ordinary bottles will burst.
The first stage
A suitable must is prepared in the normal way. This should be one which will give a light, well-flavoured wine - orange, apple, yellow plum, sultana, gooseberry or Champagne grape concentrate are all suitable. The sugar content of this must should not exceed 1 lb 14 oz per gallon (which equals 850 grams per 4.5 litres, and 1 lb 9 oz per US gallon) or the level of alcohol may be too high to permit the bottle fermentation.
An initial S.G. of about S.G. 1.075 or less will be about right.
The wine is fermented to dryness and left to clear. An S.G. of 1.000 or less is absolutely essential. Remember that chemical stabilizers or preservatives such as Campden tablets must not be added because they will inhibit the bottle fermentation.
The second stage
First of all, a small amount of sugar Is dissolved in the new wine. This provides the sugar for the bottle fermentation. The optimum amount is 2.5 oz (70 g) per gallon (4.5 litres) and on no account must this be exceeded or the bottles may explode. Next, a culture of dried Champagne yeast is reactivated in a fifth of a pint (100 mi) of water containing only a pinch of sugar. After six hours, an equal volume of wine is mixed in, and after a further six hours more wine is added to double the volume once again. The volume is doubled up in this way until the yeast is active in the full volume of the wine. (The ferment will not be very vigorous.) Be sure to take all hygienic precautions and do not leave any wine open to the air.
When the whole bulk of the wine is fermenting, siphon it into sterile, but well rinsed, champagne bottles. Leave an air space of two inches (50 mm) over the wine. Now you can use conventional white plastic dome-shaped stoppers to fit into the bottle neck very tightly and be tied down with the wire loop or muselet supplied.
For the first week after this has been done, the bottles should be stored at room temperature to allow the bottle fermentation to begin. They can then be moved to a cooler place (15 degrees C / 60 F) for longer storage and maturation. During this period of storage and maturation, Champagne bottles are moved gradually from a horizontal to an upside down position so that the yeast slides down into the stopper.
To encourage the yeast sedimentation, the bottles must be given a sharp twist every two days or so for one month before use. (Do not shake the bottles.)
When the wine is ready to serve, the yeast deposit is first removed from the bottle. The approach usually recommended Is to chill the wine to 1O degrees C (50 F) and then insert the lowest part of the bottle neck into a freezing mixture of equal parts of salt and crushed ice. A block of ice will form in the neck or stopper and encapsulate the sediment. (The wine bottle should be wrapped in a towel to stop it warming up during the time required for the freezing to take place.) The muselet is then untied, the stopper removed and the pellet of frozen wine containing the yeast allowed to shoot out of the bottle. As soon as this has happened, another stopper is banged in and tied down. The wine can then be stored and served in the normal way. Obviously this is a somewhat tricky procedure! If you want to produce a medium dry or sweet sparkling wine, the best method is to add the non-fermentable sugar lactose to taste at the beginning of the bottle fermentation.
Top and tall the gooseberries. Place them in a fermentation bin and pour on 4 pints (2.3 litres) of boiling water. Mash well, cover and leave to cool. At 20 - 25 degrees C (68 - 75 F), add the concentrate, acid, enzyme and a yeast starter, together with the sugar dissolved in enough water to bring the volume up to 1 gallon (4.5 litres). Ferment on pulp for 4 days, keeping well covered and stirring twice daily. Strain into a demijohn, top up if necessary, fit an air-lock and ferment to dryness. Rack as necessary and allow to clear. If a medium-dry or medium-sweet champagne is required, dissolve lactose to your taste in the wine. Then add 2.5 oz (70 g) of sucrose and a Champagne yeast as described above. Siphon into Champagne bottles, fit plastic stoppers and leave to mature. Chill to about 10 C (50 F) before serving.
Pick the flowers on a dry day. Comb them gently off the stalks and place them in 5 pints of water (2.8 litres) containing a dissolved Campden tablet. Cover and leave for 24 hours. Then dissolve the sugar In 1 pint (550 ml) of water and add the solution to the flowers, together with the concentrate, acid and tannin. Check that the must is at fermentation temperature, and add the yeast starter. Mix well, cover, and leave to ferment on pulp for 3 days, keeping well covered and stirring twice daily. Strain off into a demijohn, top up if necessary and fit an air-lock. Ferment out in the normal way. Rack the wine and proceed as for Gooseberry Champagne.
Original posting date
01 January 2018