The wine flaws below are listed in order of how frequently I personally encounter them, from most frequent to least frequent. The frequency of occurrences may, of course, be vastly a different for other wine drinkers and part of why it may be different is due to differences in individual’s threshold of detection. In other words, a wine that you experience as oxidized may not be detectable by someone else and therefore seem fine.
This issue of detection thresholds tremendously confounds every research effort because as usual, one man’s ceiling is another man’s floor. More uncertainty is factored into the equation because of ‘masking’, which means that problems may exist in a wine but are covered up, or not made apparent by other elements. Still research continues and studies get released but ultimately, none of them are conclusive beyond question and therefore many are only marginally useful.
There are many other possibilities about why you and I might experience a difference in the frequency and type of wine flaws we encounter. Some of those factors may include what types of wines you drink, what regions they come from, where you buy your wines, how they are shipped and stored, and whether your wine closures are mostly cork or mostly screwcap, just to name a few.
Also this list is by no means comprehensive. As we gain a better understanding of the vast complexities of wine science, strides will be made, but the process has been surprisingly slow. In the US, the University of California at Davis has done perhaps the most impressive work and of course there is also much research going on in Europe and Australia. But getting down to molecular strings, DNA, plant hormones, and other such areas of hard-science, I can see where this field would be a bit slow compared to more urgent matters such as medical research.
By the way, none of these wine flaws described below create any negative health issues with humans – they only affect aromas, taste, and our overall wine experience.
Out of Balance
Most winemakers strive very hard to achieve ‘balance’ in their wines; that is to say that none of the wine’s elements stick out or are covered up any more than any other element. For red wines the primary elements desirable to be in balance are fruit, alcohol, tannins, and acidity. As white wines generally lack tannins, this element is not a part of balance for these wines.
Often with finer wines, they do not come into balance without benefiting from a number of years of bottle age. Unfortunately some people prefer to attempt to speed up the aging process by decanting the wine; I have heard about wines being decanted for two or three days! Trust me when I tell you: if you have to decant a wine for that period of time (or even hours) it is not ready to drink. Decanting will let you drink it but your wine will loose all of the benefits it may have given you with bottle age, plus you will have drastically thrown the wine out of balance.
Most wines I have tasted in this category were either too tannic, or with whites, too acidic. Again this generally goes back to drinking wines before they were meant to be consumed. However, a vast majority of ‘new world’ wines are made and intended to be drunk young and I have tasted many of these that also were out of balance with high tannic or acidic properties. Aging this type of wine probably will not be a benefit and the imbalance is mostly due to the winemaker’s skills (or lack thereof).
Alcohol is another issue that is becoming ever more controversial with winemakers and consumers alike. The problem is more common these days due to warmer weather around the globe, which creates higher sugar levels that later, get converted into alcohol. Less than two decades ago, most red wines had an alcohol content of 11% to 12%. Now over 15% or more is normal. On the surface, this doesn’t seem like much of an increase but the difference between 11% and 15% is an actual increase of about 27% more alcohol! If alcohol overpowers the fruit or otherwise throws the wine out of balance, then the wine is flawed to a varying degree. Many winemakers are referring to this style of winemaking as creating ‘wine cocktails’.
Picking grapes earlier in the growing season would seem to make sense logically but not from a winemaking perspective. Unfortunately in today’s heat, a grape can become ripe and ready to pick based on ideal sugar levels, and yet still not achieve phenolic ripeness – that is, its seeds will still be too green and will impart unripe or ‘green’ tannins into the red wine.
As a result of this imbalance, a number of winemakers are turning to technologies such as reverse osmosis and spinning cone technology to back down some of the alcohol from their wines or beef up their fruit concentration to even it out a bit. The result of this may be successful but there is a lot of talk within the industry about too much human and technical intervention being applied to winemaking. Ultimately consumers will be the judge of this situation based on spending.
Balanced wine is perhaps one of the most difficult things for a winemaker to achieve, considering his or her available resources. And without exception, unbalanced wine is not good wine or to me even acceptable wine.
Oxygen is almost always a natural enemy of wine. I say almost because there are times, like during fermentation, that wine needs oxygen. Also aging wine in barrels and bottles with corks imparts oxygen to the wine at very low levels. Apart from when wine needs oxygen, wine will be irreversibly spoiled by it. For me there is an unmistakable and consistent note of very dark earth and mushrooms. I detect this every time I smell an oxidized wine, which is very distinctively different from other wine flaws described below.
The most likely event that you will encounter oxidized wine at occurs when you order it by the glass. As much as bartenders and wine personnel try to keep opened bottles alive, it is impossible after several days using even the best technologies available, like spreading a layer of nitrogen on the surface of the wine and/or keeping wine in a perfect vacuum. I have marveled at the number of people who will drink oxidized wine without knowing it. If you pay attention to the aromatics, eventually you will send these wines back without ever even tasting them.
I am always polite about it and ask the wine server to check to see if they agree with my assessment – invariably they do, whether they detect it or not because I am the customer. As soon as a new bottle is opened and served you will have an even deeper understanding of how oxidized the wine was. There are varying degrees of this condition but do not settle for a wine that is a ‘little’ oxidized. It is the establishment’s responsibility and obligation to ensure your wine experience is good relative to what you are ordering so don’t hesitate to send the wine back if it’s oxidized even by a small amount. We tend not to experience this flaw at home much because we don’t often (or ever) open a bottle of wine and just let it set opened for three days before we drink it.
Cooked wine is sometimes more difficult to identify because depending on how much time and heat the wine was exposed to, there can be different levels of wine damage. At its worst, it is kind of the same difference between eating a fresh tomato you just picked out of the garden, compared to canned tomatoes that have been stored for a decade. Cooked wine smells and tastes stewed or dull, or sometimes it can even smell sweet or have caramel aromas like aromas of Sherry, but it always smells cooked – like you boiled it on your cook top for awhile.
In any case the wine will almost always lack fruit and you might taste a disproportionate amount of alcohol, tannins or acidity – but little or no fruit. Some giveaways could include a cork that protrudes from the top of the bottle or shows evidence of wine on its top, a capsule other than the old-style tin or lead capsules that is stuck to the bottle (it won’t move if you try to twist it) because of seepage or leakage, or an amber edge or brownish edge to the color of the wine if it is not an extremely old vintage.
Heat ages wine so think of temperature as a kind of time machine. A wine can be aged beyond drinkability very quickly by leaving it in a hot car for even ten minutes if it’s really hot weather, or it can be damaged slowly by leaving it at room temperature for a number of months or years. From a winemaker’s creation to your glass, maintaining proper wine temperature is an extremely important element of preserving fine wine and once you taste cooked wine, you’ll know the difference.
Almost everyone who drinks wine even casually over the years is likely to encounter ‘corked’ wine at some point. This condition is known as cork taint or in chemical terms 2,4,6-trichloroanisole aka TCA. It is considered public enemy number one in the wine world because it is thought to effect perhaps more than 5% of the wines using corks, which is substantial. But not proven.
First things first: this aroma is almost unmistakable and once you experience a corked wine, there will never again be doubt in your mind about this flaw. Corked wine smells like wet newspaper, wet cardboard or sometimes a wet dog – old, musty, and moldy. Once identified, you will not even put your glass to your lips as no further confirmation is needed. Humans are extremely sensitive to this particular flaw, probably as a matter of early survival as a species: we can detect TCA at thresholds as low as 5 parts per trillion!
Many retailers will cheerfully or almost cheerfully refund your purchase price (hang on to those wine receipts) when it comes to corked bottles, although if you bought the wine ten or more years ago, then, probably not so much. Most retailers limit their refund exposure to a year or less. Before you purchase expensive wine (however you define “expensive” in this context) check with your retailer’s policy. There’s nothing worse than opening a prized bottle only to find out it is corked and if you paid high dollar, it becomes even more painful because there is no always recourse available unless you are someone that spends tens of thousands of dollars or more with a particular retailer. Being such a high-end customer would give you some extra leverage in this case.
TCA is a microbial fungi and often comes from environmental elements (small molecules combined with chlorine) that find their way into the cork itself, which is a natural by-product of a specific species of oak trees whose bark is harvested to manufacture wine closures. For you tree-huggers, removing this layer of bark from this species is harmless to the trees and in fact grows back within nine or ten years. Corked wines can occur from sources other than cork and so can corked aromas so our little flexible bottle closure devices are not the only possible culprits – just the most likely. Within the wine industry, there are enormous resources poured into researching the cork taint issue and the issue of bottle closures and believe me, screwcaps have a whole other set of problems to resolve before they can be considered acceptable for use with a bottle of fine wine. Unfortunately, the occasional corked bottle is a part of life in the wine world and it will happen to you eventually if it hasn’t already.
As usual, there is a great deal of controversy surrounding this wine flaw, also known as brett. The controversy stems from the fact that some winemakers, wine experts, and connoisseurs believe that “a little” brett is a good thing in wine, while other say that it is absolutely unacceptable. To understand this controversy we need to understand brett. Brettanomyces is considered by most to be a spoilage yeast, a little unicellular fungi, that can be introduced into wine in oh so many ways. This little beast was first identified in beer in the early 20th century and found its way into our consciousness in wine by the ‘50s. So what does it do to wine?
Brett can range from adding some interesting aromatic and flavor compounds to producing a pronounced “funk” that can be sometimes be described as sweat, body odor, a sweaty saddle, barnyard or just plain smelly. Part of this controversy arises because of differences in how we individually detect this “flaw”. As some experts point out, brett at low levels can create complexity in wine that we would not otherwise experience and many enophiles like this. Others argue that brett should not exist in wine at any level.
The truth is that Brettanomyces can be very difficult to control once it rears its singular head. As this yeast can grow in hoses, pipes, tanks, barrels and a kazillion other places. Really the only way for a winery to rid itself of the creature is to either use a lot of sulfur dioxide in the winemaking process (not a good idea generally as you’ll see below) of rip out everything but the vines and start over. Add to that a little residual sugar (sugar from the grape that is not converted to alcohol) and you have the perfect storm to feed this fungi, which allows it of course to spread.
There so far is no empirical data from testing, even with professional wine tasters whose detection levels for brett have varied significantly. But what I do know is that pretty much there is no middle of the road or indifference about the subject: one either embraces brett as adding interest to wine or one loathes brett and views it as unacceptable. Perhaps it just comes down to individual levels of detection and for some it’s just gross, others it’s interesting. Everyone agrees however that too much is a flaw and there are enough wines infected with Brettanomyces to certainly include it in this list. By the way, many very expensive and celebrated wines have a fair amount of brett.
This one is a bit tricky. It’s tricky because I really don’t want to jump into the depths of wine chemistry so I’ll try to keep it simple. You know when you read almost any wine label it states: “contains sulfites”. This is due to the fact that winemaking itself produces sulfites when the yeast converting the sugar into alcohol, runs out of food and starts eating whatever else it can find, which is often in the form of amino acids containing nitrogen. As these molecules are ‘cracked open’ by yeast, they release sulfites, a naturally occurring element found in many wine related acids. Too much of this activity however can lead to the creation of hydrogen sulfide, which is big trouble described below. Really, I am trying to keep this simple.
Add to this the fact that the winemaker has added sulfur dioxide, probably at the time of crushing grapes to begin with, and at other times during the winemaking process, and suddenly we have all sorts of sulfite possibilities in our wine. There are two main reasons for adding sulfur to wine: although this is chemically not correct, sulfur does work as an antioxidant through a chain of reactions, which is very important to wine because it spoils so quickly when exposed to oxygen, and the second reason is it is a microbial agent; that is, it kills microbes that are likely to lurk about in the process of making wine and I’m talking about the kind of microbes that we really do not want to ingest whatsoever. Wine can be made without adding sulfur but it produces many more problems than it solves.
The SO2 wine flaw occurs when there is too much sulfur dioxide used or created in the process; other flaws occur when there is too little sulfur dioxide used. Excess sulfur produces aromas of a burnt match, onion or garlic character that can usually be dissipated by exposing the wine to aeration. In more extreme cases hydrogen sulfide is formed producing aromas of rotten egg, burnt tires or skunk (known as mercaptans) and in its worst possible stage, disulfides are created producing a sewage smell that of course makes the wine completely undrinkable. As with other flaws, many wine aficionados like some hints of a burned matchstick although I have not come across anyone that enjoyed anything close to mercaptans or worse.
In some circles, the term “sulfur reduction” or just plain “reduction” is not used correctly but used to describe taste and aromatic elements such as burnt match or flinty characteristics of a wine. In wine chemistry reduction is essentially the lack of oxygen, the exact opposite of oxidization, and if managed properly, can actually enhance wine by providing a more fruit-forward style. The use of sulfur is very delicate in the process of winemaking and depends on many factors including free and bound levels of SO2 and even the wine’s pH level. You have to have a lab and know what to do with it to avoid the many problems associated with sulfur.
There are many determining factors when it comes to the use of sulfur but without it, only bad wines would be made. It is quite rare that you will come across mercaptans although a recent NY Times article about wines from South Africa point to this particular problem. Personally I love many wines from this region and have not experienced this issue. But I can see how it could happen easily because the entire winemaking process is quite complex, with not much of the romance we often associate with wine.