N.B.:The address of this page used to be www3.ns.sympatico.ca/rdsmith/horrors.htm.
It is the work of R. D. Smith, who for some reason did not continue to support
it. I captured it and offer it here--allas, without permission, since I
have no way of contacting R. D. Smith. If the author objects to my extending
an afterlife to the page, I hope he or she will let me know.
Remember: the links do not work.
I find it particularly useful precisely because it has nothing to do with medieval practices, thereby demonstrating
the ubiquity of problems with and cures for "sick" wines.
This is a compilation, from various sources, of various wine ailments and what, if anything, can be done about them. However, I don't want to discourage any would be wine makers from the hobby. Most of these ailments are rarely encountered and are usually the result of failure to observe commonsense precautions such as sterilization. If you have a comment or a suggestion please feel free to send me a note.
If any of the terms here are unclear check them out in the wine glossary.
Back to The Vintners Cellar
Last updated on Jan 21st, 1997
Cause
This is when wine turns into vinegar and can happen at any time in the winemaking process, even after bottling. It will normally occur in conditions of extremely bad storage, and in the presence of air.
Known Cure
Unfortunately there is no cure for a wine which has turned to vinegar. If you are lucky it may be useful as a wine vinegar but generally it should be dumped.
How to avoid it
Cause
This is often associated with a low alcohol content.
Known Cure
Blend with a dryer wine. Or try adding a champagne yeast which will live in the higher alcohol content and ferment more of the sugar. Do this by creating a starter bottle first. To make a starter bottle of yeast culture, take a 750 ml wine bottle and fill it half full of warm water. Add one teaspoonful of sugar, two drops of lemon juice, and a package of fresh yeast. When it is fermenting vigorously add it to the wine.
How to avoid it
Cloudy or hazy wine could have any one of a number of causes, most of which are listed below.
General CureTry moving the wine to a cold place for two or three weeks and see if it clears. If not, try filtering or bentonite, or using a good wine finings. If these fail, try pouring into the top quarter of the bottle some clear wine of the same variety. This may carry down the suspended solids.
Detection
Many hazes 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 or Pectinol. This can be prevented by adding the enzyme to the initial must for those fruits that contain a lot of pectin (eg. rhubarb, apples etc).
Known Cure
A check to whether a 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 jellylike clots or strings are formed then it is caused by pectin and it should be treated with a pectin-destroying enzyme. To treat remove one pint of wine for every gallon you have. Add the enzyme to this first, following the instructions on the bottle, stir until dissolved, then pour into the remaining carboy. Leave the wine at 60 - 70 F. (16 - 21 C.) for several days and the wine should clear, if not try using Bentonite.
Back to the Index
Back to Cloudy Wine
Detection
The presence of starch can be detected by the removal of a small quantity of must to which you add a small drop of dilute iodine solution (discard afterwards!). Even slight traces of starch will produce an unmistakable intense blue color.
Known Cure
Treat with Fungal Amylase 2209 (10%). Use at the rate of .5 tsp (2.5 ml) per 5 gallons (20 L) of wine, or 20 pounds (9 kg) of fruit.
Back to the Index
Back to Cloudy Wine
Known Cure
Fin with Bentonite as per instructions on the container. Prepare a suspension of the necessary amount in a little of the wine, carefully breaking up any lumps. Allow to sit for a couple of hours then stir into the remaining wine. Stir occasionally for the next hour. Leave for a week and the wine should clear. Rack of the sediment.
Back to the Index
Back to Cloudy Wine
Cause
Unusually the result of metallic contamination, copper, zinc or iron. Implements made of these materials should be avoided in winemaking. White, dark, purplish or brown hazes appear, often after a sudden drop in temperature, which renders the solutes less soluble.
Known Cure
For iron or copper hazes try adding a little citric acid.
Back to the Index
Back to Cloudy Wine
Cause
Caused by oxidation. If the wine is not fully stable a glassful will darken after 24 hours of exposure to the air.
Known Cure
If it is enzymatic darkening, it can be prevented by adding a stabilizing agent such as Campden tablets to the wine. Darkening can also be a result of the presence of iron. See Other Haze.
Back to the Index
Cause
Usually due to using insufficient fruit in the must. Naturally thin wines can be improved by adding one pound of either wheat, barley, maize, or sultana raisins to each gallon of must in the beginning.
Known Cure
Blend with a fuller bodied wine.
Back to the Index
Cause
Powdery, whitish flecks which appear on the surface of the wine. This aerobic bacterium, called mycoderma, is the result of allowing to much contact with air. The bacteria will turn the wine into CO2 and water.
Known Cure
Remove as much of the white as possible and filter. Add a fresh yeast culture and fill the carboy to the top. If this does not work there is no cure.
Back to the Index
Cause
This is the work of a lactic acid bacterium. The wine has an oily appearance and pours slowly, but the taste is unaffected. The wine will look like the white of an egg and will have rope like coils through it.
Known Cure
Pour the wine into a primary bucket and whip into a froth, add two crushed Campden tablets per gallon and filter.
Back to the Index
Detection
Small white crystals resembling coarse grains of salt or sugar.
Cause
This is a natural substance called Cream of Tartar, which is produced during the winemaking process. Wine grapes contain tartaric acid, some of which remains in the wine, along with citric and other acids which gives some of the flavour to wine. Most of it precipitates out as sodium bitartrate (cream of tartar) during fermentation, the remainder may end up in the wine when it is bottled and will precipitate out over time forming crystals.
Known Cure
Cream of Tartar is perfectly harmless. The easiest way to get rid of it is to decant the wine into another container prior to drinking. Commercial wineries avoid this by chilling to about 5 C before bottling. This forces the Cream of Tartar to crystallize and drop out of suspension.
Back to the Index
Cause
Usually allied to over-sweetness. If it is the result of a fermentation having ceased prematurely, adding fresh yeast directly to the must will rarely succeed, since it will be prohibited by the alcohol present.
Known Cure
Make up a starter bottle of yeast culture. Take a 750 ml wine bottle and fill it half full of warm water, add one teaspoonful of sugar, two drops of lemon juice, and a package of fresh yeast. 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 this process until the whole batch is fermenting once more. Adding nutrient to the bulk and keeping the temperature between 70 - 75 F will help.
Back to the Index
If you have used the right amount of sugar and the ferment has stopped to soon (the wine will be over-sweet and it's specific gravity to high) the fermentation is said to have stuck.
Cause
There are several possible causes, the temperature was allowed to go too high or too low; the yeast has reached it's alcohol tolerance level (the wine is done); the sugar has all been utilised (add more); too much sugar was added (dilute slightly); insufficient nutrient or acid was added initially (add more); insufficient oxygen (aerate by stirring or pouring); too much carbon dioxide (uncork and stir).
Known Cure
Make up a starter bottle of yeast culture by taking a 750 ml wine bottle and fill it half full of warm water, add one teaspoonful of sugar, two drops of lemon juice, and a package of fresh yeast. When it is fermenting vigorously add an equal quantity of the stuck wine. When all is fermenting well, again add an equal quantity of the wine, and continue this process until the whole batch is fermenting once more. Adding nutrient to the bulk and keeping the temperature between 70 - 75 F will help. If the wine was fermenting for a long period of time (several weeks) try making the starter bottle using a high alcohol tolerant yeast such as Champagne yeast.
Back to the Index
Cause
If you have killed your wine yeast by adding Sodium Metabisulphite too early, all is not lost. This is treated very similar to a stuck ferment or a low alcohol wine. The only difference is that you may want to use a Champagne yeast, and you definatly must wait 24 to 48 hours before adding the new yeast. This will allow the chemicals that were added to disapate.
Known Cure
Make up a starter bottle of yeast culture by taking a 750 ml wine bottle and fill it half full of warm water, add one teaspoonful of sugar, two drops of lemon juice, and a package of fresh yeast. When it is fermenting vigorously add an equal quantity of the stuck wine. When all is fermenting well, again add an equal quantity of the wine, and continue this process until the whole batch is fermenting once more. Adding nutrient to the bulk and keeping the temperature between 70 - 75 F will help.
Back to the Index
THIS LINK WORKS: Return to Links Page
Rev 11/99