Most beer is force carbonated with carbon dioxide to give it fizz, but bottle-conditioned beers are bottled with a small amount of yeast. This yeast naturally carbonates the beer and allows it to continue to ferment and mature inside the bottle, leading to a deeper flavour and character.

You need to be careful when pouring these beers because you do not want to pour the yeast from the bottom of the bottle into your glass. There is nothing harmful about the yeast (in fact, it is a probiotic organism and offers many health benefits), but it can disturb the flavour and cause indigestion. To avoid, follow these steps;

• Much like a standard pour, tilt your glass at a 45 degree angle and pour your beer into it, however use a slightly gentler rate of pour than with a non-bottle conditioned beer
• When your glass is approximately half to three-quarters full, tilt it back upright and continue to pour the rest of the bottle. This will create the proper amount of foam for your pint
• Towards the end of the pour, you will begin to get to the yeast. Watch carefully; when you notice the stream coming our of your bottle becomes cloudy or unclear, stop pouring. With practice, you will learn to judge this without pouring any yeast into your glass
• Discard the rest of the beer in the bottle. You may be surprised by how much is left, but don't drink it - it won't taste good