—FAULTS AND REMEDIES
WHILST something must be said about faults and diseases of wine, it should be emphasised at once that several of these disasters which can befall your wines are rarely encountered. Observance of commonsense precautions will ensure that your wines are sound, and you may never need to refer to these particular pages. I hope you do not! —but "just in case" there are listed here some of the disasters most probable to be encountered.
ACETIFICATION . . . or formation of vinegar. This will normally only occur in conditions of extremely bad storage, and in the presence of air. Therefore keep your bottles full. If it is noticed in the early stages—there is a very slight smell of vinegar and an acid taste—it can probably be halted by adding one Campden tablet per gallon, waiting 24 hours, and then introducing a vigorously fermenting fresh yeast. In the later stages the smell of vinegar will be pronounced, and indeed what you now have is wine vinegar. Remedy: Use it for cooking or pour it down the drain!
Sometimes a wine will smell vinegary but not taste acid, and this is the effect of ethylacetate, produced by wild yeasts present on the fruit. Prevent. this by adding one Campden tablet per gallon 24 hours before your chosen yeast.
OVER-SWEETNESS. The bugbear of the beginner. It can be avoided by not using too much sugar initially and always using a nutrient (see pp. 21 and 22). Remedy: Blend the vine with one from similar ingredients which is over-dry, or with dry rhubarb wine, which will take up its flavour. See also "Low Alcohol Content."
LOW ALCOHOL CONTENT. Usually allied to oversweetness. If it is the result of a fermentation having ceased prematurely, adding fresh yeast direct will rarely succeed, since it will be inhibited by the alcohol present. Remedy: Make up half-a-pint of fresh juice with 1 oz. sugar and some fresh yeast and nutrient as a "starter." When it is fermenting vigorously add an equal quantity of the low-alcohol wine. When all is fermenting well, again add an equal quantity of the wine, and continue the process until the whole is fermenting once more. Adding nutrient to the bulk and keeping in a temperature of 70 deg. F. will help.
OVER-ACIDITY. A slight over-acidity can often be corrected by stirring up any yeast deposit and causing a malo-lactic ferment. With a strong wine slight dilution will help to reduce acidity, and with a weak, dry one the overacidity can often be masked (but not corrected) by the addition of a little sugar. BEST Remedy: Add glycerine, at the rate of 5 %, or 1 pint to 2 ^ galls. A third of an ounce of procipitated chalk to 1 gallon (preferably added before fermentation) will also correct over-acidity. Added afterwards it may leave a taste. (See Rhubarb Wine recipe.)
MEDICINAL FLAVOUR. The result of insufficient acid in the must. If the fault is but slight the addition of a little citric acid to the finished wine may help, but if the flavour is pronounced little can be done.
MUSTY FLAVOUR. Some writers describe this as a "mousey" taste, but I have never tasted a mouse! Actually this is probably a corruption of the French wine term "moisi," or mouldy. Caused by wine standing overlong on dead yeast, particularly baker's yeast. Prevent this fault occurring by methodical attention to racking. Once a firm yeast deposit has formed—rack! Remedy: See "Taints and Smells."
TAINTS AND SMELLS. Not always readily identifiable; they can be caused by damaged fruit, bacterial action, tainted plastic containers, bad casks, or proximity of wine to strong smells (onions, paraffin, etc.). They can occasionally be removed by charcoal treatment but it is necessary to experiment to discover how much charcoal is needed. Add a small quantity to a measured quantity of wine, stir two or three times during first 24 hours. Allow to settle. Leave a further day, then rack, and filter to remove particles of charcoal. Some of the flavour and colour may also be removed. If dose is satisfactory treat bulk of wine in the same way.
METALLIC FLAVOUR. Sometimes encountered when wines have been made with tinned fruit, juice, or concentrate, or when ferrous metals have been allowed prolonged contact with the wine. Remedy: Avoid "unsafe" metals.
FAILURE TO CLEAR. Usually the result of over boiling ingredients (see PECTIN HAZES) or of hastening unduly the initial straining, which should be both slow and thorough. Remedy: Move wine into cold place for two or three weeks and see if it clears. If not, try filtering through asbestos pulp (see p. 33) or using a good wine finings, such as Serena. If all of these fail, try pouring into the top quarter of the bottle some clear wine of the same variety. This will often carry down the suspended solids. Isinglass or gelatine as finings are tricky, and not recommended for the beginner.
PECTIN HAZES. Many hazes in wines are due to gelatinous solutions formed by pectins in fruits, and are aggravated by initial boiling. They can be avoided by using a pectin-destroying enzyme such as Pektolase, Pectozyme, Pectinol, etc. To improve the yield of juice when making fruit wines the enzyme should be added to the pulp of the fruit, using H oz. to each 8 lb. pulp (H oz. each 5 lb. blackcurrants). If the juice is allowed to stand at room temperature overnight or longer the enzyme will act satisfactorily, and the juice will clear.
A check that any haze is caused by pectin can be made by adding 3 or 4 fluid ounces of methylated spirit to a fluid ounce of wine. If jelly-like clots or strings are formed, then the haze can be regarded as pectin and the remaining wine treated with Pectozyme. For each gallon of wine ^ oz. of Pectozyme should be added to ^ pint of wine and the wine kept warm (70-80 deg. F.) for four hours, stirring at intervals. Strain through muslin and add to the bulk of the wine. Leave the wine at 60-70 deg. F. for several days. The pectin haze should clear but if it does not use asbestos filtering medium.
STARCH HAZES. Treat with another enzymatic preparation, Amylozyme. Mix / oz. Amylozyme 100 with 2 to 3 oz. water and leave for two hours, stirring or shaking, if in a bottle, at intervals. Meanwhile put the wine in a preserving pan and heat to 170 degrees F., and hold this for 20 minutes. Cool the wine to 110 degrees F. and stir in the diluted enzyme. In about one hour the reaction will be complete and the temperature of the wine should again be raised to 170 degrees F. and held for ten minutes. After cooling the haze will settle out and the wine should be racked.
COLOURED HAZES. Usually the result of metallic contamination, copper, zinc and iron being the usual causes. Containers or implements of these metals should be rigorously avoided for fermentation purposes or white, dark, purplish or brown hazes may appear, often after a sudden drop in temperature, which renders the solutes less soluble. Remedy: For iron or copper hazes add a little citric acid; this often works.
DARKENING—is most commonly caused by oxidation. If a glassful of finished wine darkens after 24 hours exposure to the air it is not fully stable. If the cause is enzymatic, darkening can be prevented by adding 2 Campden tablets per gallon as a stabiliser. Darkening may also be due to the presence of iron, which can be corrected by the addition of a little citric acid (/ oz. to 5 gals.).
TOO MUCH COLOUR. If you wish to decolour a white wine use clean eggshells which have been immersed in boiling water and crushed, or the charcoal treatment under "Taints and Smells."
HARSH FLAVOUR. Add glycerine to taste, or treat as for "Darkening," or use gelatine firings. (See "Clearing" (p. 31).)
FILTER-PAD FLAVOUR. Caused by failing to wash the filter pulp with water or wine before filtration. The first wineglassful of wine through the filter should always be thrown away.
FLATNESS OR INSIPIDITY. The result of insufficient tannin in the wine. Remedy: Add grape tannin or a small quantity of strong tea (up to 1 tablespoon per gallon).
THINNESS, or lack of "body." Due to using insufficient fruit as the basis of the wine. Naturally thin wines, such as plum, can be improved by adding up to 1 lb. of wheat, barley or maize to the gallon when making. Thinness in a finished wine can only be overcome by judicious blending with one of considerably more body. Marrow wine and robust grain wines are excellent for this purpose, since they usually have good body. Regularly using a Campden tablet per gallon in the must 24 hours before adding the yeast will also improve the wine by putting into it a little glycerine.
FLOWERS OF WINE. Powdery, whitish flecks appear on the surface of the wine and if left unchallenged wilt rapidly increase and will turn your wine first to carbon dioxide and then to water. It is caused by an organism like yeast, mycoderma, an aerobic bacterium, and is usually the result of admitting too much air to the fermenting vessel. Remedy: Remove as much of the surface flecks as possible, filter through unmedicated cotton-wool or filter papers, introduce some vigorous fresh yeast, and fill the fermenting bottle as full as possible to exclude all air. If a substantial film has been formed there is no remedy.
ROPINESS. The wine takes on a repellent, oily appearance and pours very slowly, like treacle, but the taste is unaffected. The wine will look rather like the raw white of an egg and in it will appear rope-like coils—hence the name. This is the work of the lactic acid bacterium. Remedy: Whip the wine into a froth in a polythene bucket, add two crushed Campder tablets per gallon, and filter through asbestos pulp or filter paper.
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