wine bottles, clear vs colored

It's traditional for reds to come in green bottles, either light or dark green depending on the variety.

You might be able to find some cheap reds in a clear bottle, but then it would probably have a screw top.

What Alleycat said.
Some people decant red wine and most decanters are clear glass.

I suspect it has something to do with the light breaking down something in red wine affecting its taste.
Only exception I can think of is Chianti which is sometimes in clear glass wrapped in wicker.

Using green bottles for red wine to block UV seems to make sense, but I'm not sure if the science holds up. I always figured it was done to hide the sediment in red wine.

I seem to recall hearing somewhere that in the old days, colored glass bottles were due to impurities in the manufactoring process, and the costs associated with having clear glass. Now, in addition to keeping colored glass because of tradition, it helps protect against the breakdown of tannins and other components by light.

This is easily researched, but the basics are that red wine is more sensitive to natural sunlight and stored in darker bottles. White wines tend to be drunk immediately and are often refrigerated which blocks natural sunlight. Aging cellars are dark and usually cool for the same reason.

Also, some wines are traditionally bottled in very dark green or amber bottles to help hide the natural sediments in the wine.

Jeff

These things will also tend to depend on the country. France is especially regulated (self-regulated, too) and the shape of the wine bottles even means things about the region it came from, etc.

Oddly enough, I just bought a Merlot (from Canada) in a clear glass bottle. It wasn't one of the more expensive ones, but it was ok. As for the screw top issue, they are discovering that screwtop or cork doesn't make much difference to the wine aging. Only bottles with natural cork corks will actually age in bottle, the artificial corks or screw tops won't, so they taste younger. With that disease that is affecting the cork trees, real cork in wine bottles is soon going to be something only for really expensive wine, or may stop entirely soon.

I've also read in many books the concept of UV, but I think it is myth because even clear glass blocks UV. That's why you won't sunburn infront of a closed window. However, yeast are different critters than us so that does not mean that there isn't something else about light that can penetrate glass. However the yeasts used in white vs red wines are basically the same, not always I know, but often enough used in both that I doubt there is a difference. Maybe it's not the yeast? There are more tannins in red wine, maybe light does something to them? I think mainly it has to do with being able ot catalog or count the wine in your cellar easier and as others have said, to hide sediment on your wines that have not been filtered or properly decanted and then after that it's just tradition.

GeorgeK said:

I've also read in many books the concept of UV, but I think it is myth because even clear glass blocks UV. That's why you won't sunburn infront of a closed window. However, yeast are different critters than us so that does not mean that there isn't something else about light that can penetrate glass. However the yeasts used in white vs red wines are basically the same, not always I know, but often enough used in both that I doubt there is a difference. Maybe it's not the yeast? There are more tannins in red wine, maybe light does something to them? I think mainly it has to do with being able ot catalog or count the wine in your cellar easier and as others have said, to hide sediment on your wines that have not been filtered or properly decanted and then after that it's just tradition.

Click to expand...

I always thought that, even though the compounds in said wine are most susceptible to degradation by UV light, they are also susceptible to degradation by visble light.

Usually, store bought red wines come in coloured bottle, BUT
Good red wine is only gotten from the farmers of that grape, and if you buy from them, they give you a clear bottle.
Usually 2 liter one.

GeorgeK said:

I've also read in many books the concept of UV, but I think it is myth because even clear glass blocks UV. That's why you won't sunburn infront of a closed window.

Click to expand...

Slightly off-topic, but clear glass does not block all UV. From what I've read, it blocks UVB, but allows UVA through. You might not burn, but you can still get skin damage from UV radiation. And if you're allergic to UV or have photosensitivity, you'll still be at risk. To illustrate, I have porphyria, a disorder that causes extreme photosensitivity, and when I travel by car, I have to wear long sleeves or cover up with a blanket, because the sunlight coming through the windows will burn me.

Red wines - Bordeaux (Cabernet and Merlot grapes) mainly - are sensitive to sunlight as they age.

That's why good red wines coming from small batches are put into dark bottles and aged in dark caves. They are usually fitted with the traditional cork cap which is kept moist by slanting the bottle during the aging process. The year on the label is important.

Larger wineries use oak barrels for aging and so they don't really care about the glass color or the cap type. Those wines are expected to be consumed shortly after being put on the market. The label usually doesn't mention the year - it's not necessary because the winery has already determined the wine is prime for consumption NOW. It's a bit of an overkill - if not a nice way to produce vinegar - to try and age a bottle of red wine that has been already aged in a barrel.

-cb

Oldbrasscat said:

Oddly enough, I just bought a Merlot (from Canada) in a clear glass bottle. It wasn't one of the more expensive ones, but it was ok. As for the screw top issue, they are discovering that screwtop or cork doesn't make much difference to the wine aging. Only bottles with natural cork corks will actually age in bottle, the artificial corks or screw tops won't, so they taste younger. With that disease that is affecting the cork trees, real cork in wine bottles is soon going to be something only for really expensive wine, or may stop entirely soon.

Click to expand...

Thank goodness. I'm terrible with corkscrews.