Freezing wine is an inadvisable action which occasionally happens for various reasons. For example, perhaps someone placed wine in the freezer to quickly cool it, only to forget to take it out. Or perhaps someone leaves wine in the trunk of a car overnight in the middle of winter.
Does this change the alcohol content of the wine? Generally speaking, it does not.
Although there are various ways freezing can affect wine, and although there are various reasons why people should avoid freezing their wine (to include changes to taste and safety issues), it generally does not affect the level of alcohol within the wine itself.
How Does Alcohol Content Change?
There are two primary ways in which the alcohol content of a liquid beverage can change. The first is a removal or addition of other components of the beverage (especially water). Some ways this can be accomplished include evaporation or boiling. In the world of alcoholic drinks, boiling liquids to increase alcohol content is called “distillation”.
Liquors are created by distilling various fermented alcoholic mixtures. In fact, brandy is made by distilling a certain type of wine to increase the alcohol content. Diluting a drink (often by adding water), works in the opposite direction and reduces the alcohol content of a drink.
The second way to increase the alcohol content of a liquid is through chemical reactions. Chemical reactions can occur through the addition of large amounts of energy (such as through the use of an electrical current, burning a material, or using living organisms).
By far the most common reaction which creates alcohol is fermentation, in which yeast cells consume sugars to produce alcohol and carbon dioxide. In fact, this is how all alcoholic beverages are created.
If there is neither an addition or removal of liquid, nor a chemical reaction, there is no mechanism which can change the alcohol content of the beverage.
How Does Freezing Affect Wine?
Freezing a liquid is a physical change. A physical change is one in which the “phase” of a material changes, without altering the underlying chemical structure of the substance.
For example, when water freezes and turns into ice, or boils and turns into water vapor, the actual molecules of water do not change. Instead, the way in which the molecules interact with each other changes.
In liquid water, the water molecules move past each other, while in ice, the water molecules are connected to each other in a crystalline structure. However, the water molecules are still identical. This means freezing wine does not change the chemical composition of most of the wine.
Wine itself is more than 80% water – this water may freeze but will still be water.
Will Freezing Wine Affect Alcohol Content?
With one caveat, freezing wine will not affect its alcohol content. Alcohol does not undergo a chemical reaction when its temperature is lowered. In fact, pure ethanol has a freezing point far below any temperature a standard home or commercial freezer would reach, meaning the alcohol would not even undergo a phase change to a solid, let alone a chemical change.
If the wine is allowed to melt back to a liquid, the alcohol content should be the exact same. The alcohol content (up to 15% of the wine) and the water content (more than 80% of the wine) should return to the exact same original state after thawing.
However, the caveat is that wine will often be in a slushy state after being placed in the freezer. If someone removed either the solid or liquid part of the “slush”, the two components would have different alcohol content levels.
This is the case because the water in wine will be partially frozen, while the alcohol in the wine will be completely liquid. Of course, most wine lovers would never consider doing such a thing to wine, making this a largely hypothetical scenario.
Possible Downsides to Freezing Wine?
Although freezing wine will not change the alcohol content if it is allowed to melt back into a liquid, there are various reasons why freezing wine is not a good idea.
Firstly, there are safety concerns with freezing wine. Wine is mostly made out of water, and water expands when frozen. Most wine bottles are made out of glass, meaning there is a possibility the bottle could crack or explode from the expanding water. The sharp shards of glass would present an obvious safety hazard.
Another possibility is that instead of exploding, the expanding ice would push out the cork or screw on cap of the bottle. Although this is not as dangerous as an exploding bottle, it still causes issues.
If the cap of the bottle is removed, it would expose the wine to air for however long the wine is kept in the freezer. This oxidation of the wine is far from the ideal scenario in which wine would be properly sealed. It can spoil the taste of the wine.
If the frozen wine is stored in the same compartment as frozen foods, the taste of the foods could even leech into the wine. From a taste perspective, the exposure a wine can get to the elements from freezing can greatly diminish the wine drinking experience.
Benefits to Freezing Wine?
Are there any benefits to freezing wine?
For the most part, there are no real benefits to freezing wine. If a bottle of wine is properly sealed, there is limited risk of the wine spoiling over the course of its shelf life. The alcohol content of the wine helps preserve it from being spoiled, and the sealed bottle keeps the wine from being exposed to excessive oxidation.
Many types of food (meat, ice cream, frozen fruits, etc) are frozen specifically to prevent spoilage, but this simply does not apply to an alcoholic beverage such as wine. There also is no real evidence that freezing wine enhances its taste (in fact, most wine aficionados would argue that the opposite is the case).
With that in mind, there is simply no reason whatsoever to freeze wine. If someone wants alcohol with higher alcohol content, simply buying a stronger wine, or even buying a wine-based spirit (such as brandy) would be much preferable to trying to change the wine through freezing.
If someone accidentally freezes a bottle of wine (perhaps accidentally left in a freezer or inside of a car during the winter), he or she can simply let the wine melt and have a taste, before deciding whether the wine is good enough to continue drinking.
Freezing wine does not change its alcohol content in any significant way. The only ways to change the alcohol content of a drink are to either add or remove the non-alcoholic portion of the drink (through evaporation, boiling, diluting, etc) or through chemical reactions such as fermentation.
Freezing wine will simply turn it into a slushy drink which will return back to a liquid with the same alcohol content if thawed. This is the case because neither alcohol nor water (the two most common ingredients in wine) undergo any chemical reactions when freezing or thawing.
Moreover, there are several reasons people should avoid deliberately freezing wine. This includes the risk of a wine bottle exploding or cracking, as well as the possibility of the wine cap breaching, which would damage the wine’s taste over time.
Freezing or thawing wine will not affect the alcohol content of a wine in any way but will most likely negatively affect the taste of the beverage. With that in mind, there is no real reason for anyone to freeze wine.