Faults Found In Wine Making - Diagnosis of Faults in Wine

The Diagnosis of Faults in Wine To use the table, look for the fault in the left-hand column. In the right-hand column is found either the cause or reference numbers for later diagnosis.

Visual Faults
1	Haze or sediment	See 36
2	Patches on surface	Mycoderma infection.
3	Skin on surface	Mycoderma infection.
4	Oil on surface	Pre-acetification.
5	Wine thicker than usual	Lactobacillus infection.
6	Ropes in wine	Leuconostoc infection.
7	Wine looks like slime	Toropsulosis infection.
8	Layering in wine	Wine recently blended. Allow longer aging.
9	Wrong color for style	See 42
Taste Entries (Taste/Smell )
10	Smell of bad eggs	Hydrogen sulphate in wine.
11	Vinegar	Acetified wine.
12	Tart
13	Acetic acid
14	Pear drops
15	Mousel	Butyric acid bacteria infection.
16	Rancid
17	Fishy
18	Burnt	Wine either over-cooked or intended as Madeira type. Charcoal fine if former.
19	Caramel
20	Corked	Cork infection. Discard wine.
21	Swimming bath	Cork infection. Discard wine.
22	Asbestos	Filter medium not washed before use. Discard wine.
23	Cardboard
24	Paper
25	Earthy	Wine over-fined with Bentonite or dirt from ingredients.
26	Yeasty	Young wine. Allow to mature.
27	Aldehydic	Young wine. Allow to mature.
28	Astringent	Too much tannin.
29	Over or under acid	Reduce with calcium carbonate Or Add acid and mature
30	Bitter	Lactobacillus infection with mannitol.
31	Cooked	Ingredients boiled too long.
32	Prickly	CO2 still present. Fermenting or malolactic fermentation.
33	Musty	Wine on lees too long. Try charcoal.
34	Medicinal	Too little acid. Addition has poor chance of improving wine.
35	Mousey after taste	Lactobacillus infection
36	Haze with bubbles	See 37
36	Haze without bubbles	See 39
37	SG falling	Active ferment. Continue
38	Acidity falling	Malo-lactic ferment
38	Acidity static	Secondary ferment
39	SG 1020 or more	Stuck ferment (see entries)
39	SG 1020 or less	See 40
40	Haze with sediment	See 41
40	Haze without sediment	See taste entries to find cause
41	Wine recently racked	See taste entries
41	Wine not recently racked	Rack and reassess after 3 months
42	Wine meant to be red	See 43
	Wine meant to be white	See 44
	Wine meant to be Rosé	See 45
43	Wine too dark	Too long on pulp, or too much fruit
43	Wine too pale	Not enough pulp ferment, or too little fruit
44	Wine too dark	See tests
44	Wine too light	Not enough fruit
45	Wine too dark	Too long on pulp
	Wine too light	Not enough pulp ferment
	Orange tint in wine	Poor blend of red and white
46	Brown color in wine	If sherry or dessert wine correct
46	Brown color in wine	If white wine oxidation has occurred

WINE BOTTLE STORAGE AND TEMPERATURE

Cooler Is Better

When storing your precious homemade wine for the long-term--after it has been bottled--it is usually understood that cooler is better. Most wine experts agree that the ultimate storage temp- erature for most bottled wines is 55 degrees F.

Cooler temperatures slow down the effects of oxidation. The same is true with reduced light exposure. Both help to reduce the symptoms caused by having too much oxygen in a wine.

But, don't get too hung up on temperature. The improvement is only marginal for each degree you go down in temperature. For instance, a 65 degree basement is much, much better than an 75 degree dinning room. This 10 degree improvement is a major benefit. But a 55 degree storage area is only marginally better than a room that is 65 degrees.

While there is some benefit by going on down to 55 degrees F. from 65 degrees, it is only minor as compared to getting the wine away from a 75 degree F. room.

Minimize Temperature Fluctuations

Your focus can be better served by finding a reasonably cool place to store your wine that has a stable temperature. For example, if I had a choice of storing my wine in a room that was a constant 65 degrees or a room that had temperatures that fluctuated between 45 and 65 all the time, without question I would choose the stable 65 degree room.

Temperature change is hard on a bottle of wine. It wears the wine down. Eventually, this constant rise and fall in temperature will give the wine a flabby flavor, weak aroma and a character that lacks depth or complexity. Please realize that this does not happen overnight, but with each rise and fall in temperature the wine will lose just a little bit more of its quality each time.

How Temperature Changes Affect A Wine

The reason for this deterioration in quality is because of expansion and contraction. Changes in temperature causes things to expand and contract. But not all things expand and contract the same amount.

In the case of a bottle of wine, both the glass bottle and the wine itself expand and contract along with temperature changes. But they expand to different degrees. The wine in the bottle expands and contracts much more so than the glass bottle in which it is being contained.

So as the temperature of the bottle of wine rises, the wine inside expands more so than the glass. This causes pressure within the bottle. In turn, this pressure causes a small amount of the wine's aroma or bouquet to slowly escape through the cork.

In more rapid temperature changes there may also be some notice- able seepage of the wine itself through the cork. But this is only half of the story.

When this bottle is cooled back down again, the wine contracts more than the glass causing a vacuum within the bottle. As a result air is slowly sucked through the cork into the bottle.

So what you have is a situation where a wine's good aroma is being exchanged for bad, damaging air with each up and down cycle of temperature. One could say that the bottle is actually breathing with each cycle. It exhales its bouquet; and inhales oxidative air--not a good trade.

When this temperature change cycle happens two or three times through the life of a bottle of wine, not much effect in quality is noticed. But when this happens on a continual bases, then there is usually a detectable change for the worse.

Check Your Temperatures

If you are not sure where you stand with your wine storage area, it might be in your best interest to monitor the different temperatures that occur over a given period of time.

You might surprise yourself. Quite often areas thought to have stable temperatures such as fruit cellars or closed off portions of basements, in fact, can have daily temperature fluctuations as high as 5 to 10 degrees.