From early September until sometime in October, the beloved half-fermented grape juice known as burčák enjoys its yearly star turn. Pale gold, cloudy, yeasty and honey-sweet, ephemeral burčák is nothing more than an early stage in the production of wine. Increasing in alcohol even as it is poured, it varies in strength — in optimal conditions, the last sip in the pitcher can be quite a bit stronger than one from just an hour earlier.

We consulted a panel of experts for their stories about burčák. To get started on your own story, look for it at a winery — often sold in reused plastic water bottles — or hit one of the city's better wine shops. But be careful. The poisoned feeling you might have after too much burčák comes from a very real poison: carbon monoxide given off by the yeast as it consumes the very grape juice you're consuming.

Ondřej Maťek

Manager, U Sudu wine bar

Every year, there are people who come here just for the burčák season, and then we do not see them the rest of the year. For example, there are three gentlemen who come over and always order three liters of burčák. And then three more liters and three more and so on and you can imagine the results. Young people especially do not know what burčák can do, and then they throw up all over the place.

Libor Ševčík

Hospodářské Noviny food and wine writer

Burčák should be drunk only in wine cellars. In Prague you can drink it in good wine shops, places where it was brought overnight and you drink it the next day. I drink it only occassionally, when I know where it is from. Yesterday I had some at a celebration — I knew they brought the burčák from the cellar just one hour earlier and we drank it within another hour. Its taste worsens very quickly: The state of burčák often lasts just two hours — then it turns into rezak, then young wine and finally wine. If I were to talk about it to someone who does not know burčák, I would say that the process of fermentation continues when you drink it, inside you, and though it can taste like juice, the alcohol is still there.

Radim Bobek

Rybí trh sommelier Manager, Wine Shop Ungelt

There are two approaches to burčák. Sometimes wine producers sell it because they need quick cash at this time of the year. For others, it is a waste — why sell burčák when you can wait and produce real wine? It's best enjoyed at the source: It should not be transported, and it tastes best when made out of aromatic grapes like tramin. It is said that you should drink as much burčák as how much blood you have in your body. Well, if you do, then the next day ... I am sure you understand.

Martin Pastyřík

President of the Association of Sommeliers

You should know where it comes from. Burčák can often be bad, and sometimes what they sell is not real burčák at all. They just add substances that resemble it — some alcohol, some juice, some sugar — and then they sell it. I drink a liter or so every year. It's best when made from early varieties of grapes, such as iršai, which has a mild flavor of musk. I had a few bad experiences when my wife or I bought it and it turned out to be horrible. Also, if you do not close the bottle well, it can spill all over your car.

Guillaume Lahournat

Kampa Park sommelier

I like to drink it above all when I'm thirsty — it's like a lemonade for adults. In France, we drink mout de raisin, a wine at the beginning of fermentation that has very little alcohol but a lot of sugar. One of my favorite memories is of the first time I was allowed a glass, despite my young age at the time. It was at the first light of dawn and we were setting up my uncle's dove blind, preparing a fire, gathering chestnuts and hunting for mushrooms for lunch. The cold bit at my cheeks. Around 11 one of my uncle's friends brought some mout and we grilled the chestnuts, fried the mushrooms a la persillade and had one glass of mout — just one, because I was so young. I found it extraordinary. But of course it was the setting that made it seem so magical.