Okay, let’s start with some basic taste tests:
Do you eat your cheese cold or do you insist on letting it reach room temperature?
Does your stew taste better the next day or you don’t care?
Does your bread taste better fresh out of the oven or cold the next day?
Do you season your meats at least 20 minutes (or longer) before cooking or you don’t think it matters?
Frankly, if you don’t care or if you can’t taste the difference, it really is a waste of your time to aerate your wine. It’s irrelevant if sommeliers do this, or professional wine tastings do this or anything else.
However, I have yet to find anyone that can’t taste the difference between the following 2 samples. Open a bottle of any wine (red, white, sparkling, boxed…), pour 3 ounces into a glass (shape of glass of your choosing, shape being a whole other discussion point), vigorously pour the rest of the bottle into a container (thereby aerating it…) that doesn’t have a lingering odor (i.e., not a coffee pot or lady’s slipper) and then pour another 3 ounces into a same shaped glass. Smell and taste. Which one do you prefer?
You now have your answer.
If you would like an explanation
http://en.wikipedia.org/wiki/Aroma_of_wineAnd since I know you are just dying to know, yes, I aerate all of my wines except Champagne (and some of the major Champgane house are promoting even this). In fact, I double aerate all of my wines in that I pour all of them into a cheap decanter and then immediately pour them back into the original bottle using a large, plastic funnel so that the wine being served is easily identifiable. Doing this also allows me to note whether there is sediment, which I, thus, eliminate.
I have tried aerating Champagne but it loses too many bubbles for my taste standards.
And there we are back to where we started. Can you taste the difference? But if you don't try these things and just dismiss the practices of others - how will you ever know? And isn't that partly why we are on this board?
