When I order wine by the glass at some restaurants, they bring the bottle to the table and show it to me. At other places, they just bring a glass already poured. How do I know what's in it?
Oooh, there could be anything in that glass, couldn't there? You might have ordered grand cru chablis and they could have brought you a glass of budget savvy blanc. Without clapping eyes on a bottle, how would you ever know? Well, some people would pick it easily but there's no shame in not being able to.
If you're not confident about detecting the difference between an obscure eastern European varietal and a professional sportsman's urine sample - and you would not be on your Pat Malone in this - take comfort in the fact that by-the-glass substitutions are not the norm. They're more likely to be stuff-ups than conspiracies.
That said, I like to see glasses of wine poured at the table. It's something a lot of us expect of a good restaurant. Many people order wine by the glass because we want to try something new without committing to a whole bottle; we may not know how it's meant to taste. It's reassuring and helpful to see the bottle. A glance at the label helps us remember what to order next time, or buy at the bottle shop. But for the restaurateur, pouring at the table is more cumbersome and costly than doing it quickly behind the bar. It's more common at ambitious eateries with corresponding prices.
In recent years, many restaurants have invested in equipment that promises to keep open bottles of wine fresh for days. This minimises their risk of being left with unsaleable wine if they sell only a couple of glasses from a particular bottle over a day or two. The upside for wine lovers is that opened wine preserved this way should be in good nick and restaurants will be more willing to offer sexy, pricey wines by the glass. The downside is that the wine bottle must remain hooked up to the dispenser. If it's not one of those help-yourself set-ups, your glass will come to your table already poured, or if the restaurant is charging a lot and trying hard to compensate for the lack of ceremony, you might see it arrive in a miniature carafe or decanter. As with food, if you think you've been served something you didn't order, don't hesitate to query it.