Bottling time

[spuds]

I have been brewing for quite some time and have never experienced this before and now it has happened twice in a row. My last 2 brews (as I am out of grain) have been festa brew west coast pale ale and brown ale. Over the years when I was bottling, I bulk primed. Which always turned out perfect. Last couple years I have been kegging so I always have 3 liters or so left over. I have usually put half to 1 teaspoon of table sugar per bottle and naturally carbonated. The last 2 brews when I was adding the sugar have been a panic to get the cap on quickly as they will foam out of the bottle. I was scared that fermenting wasn't done but they are carbonated perfectly after a month or so. Whats goin on here, any ideas?

[the-mailman]

Just a guess, but after fermentation is done there is usually some residual dissolved CO2 in the beer. Adding the sugar causes nucleation and the trapped CO2 is quickly released. The same thing happens when you drop a mentos into a bottle of pop.

[GuingesRock]

That sounds like what is happening. As an alternative method you could heat the sugar with water in a Pyrex jug, in the microwave, to dissolve/sanitize, let cool and squirt a measured amount in each bottle with a sterile syringe.

With an open fermentation setup, the CO2 will come out of the beer (time dependant), but in a closed system with 100% CO2 in the head space, at 12C and atmospheric pressure, carbonation will remain at 1 volume indefinitely. At higher temperature, say 20C the carbonation will be a less, according to that graph on solubility of CO2 in beer at different temperatures. This time around you may be using a different fermentor setup, or the beer might be colder, resulting in more CO2 dissolved in the beer?

On the other side of the coin, if the bottles, this time around, were warmer, that would warm up the beer and it would be more likely to foam from the nucleation of the sugar, due to the lower solubility of CO2 in warmer beer.

Dissolving and sanitising the sugar in hot water should solve the issue. Sugar from the packet is said not to be sanitary, and might cause off flavours because of that.

[McGruff]

I do exactly the same thing, but use Coopers Carb Drops. I don't get any foam at all. Each tab is good for 375 ml of beer.

[spuds]

Thanks for the replies. Maybe the brew was a little cool when I added sugar. Just never happened before.