Blasted

I returned from Legnica and went into my garage and down into the cellar where I made a shocking discovery. The place reeked of ginger. All nine remaining (of ten) bottles of ginger beer that I brewed about six weeks ago had exploded. Totally gone - blasted. The cellar was full of shattered glass. Last autumn's cider, standing on either side, survived the carnage.

Below: the scene as it befell me. The smell of ginger cannot be captured. In the corner, under the rack, is a round sump-hole - it was full of ginger beer (about a litre and half of it)!

Below: close up - between the rows of cider bottles there were two rows of ginger beer - nothing but shattered remnants remained. One cider bottle was destroyed as collateral damage (third bottle in row to the right). And a strong whiff of ginger in the air!

Why? I have heard such stories from my youth (Richard M, for example, from Ealing, had some ginger beer explode explode with such force that glass was embedded in his bedroom wardrobe in which he stored it). But I had taken due precautions - this was a second batch, after all... I thought I knew what I was doing...

I'd bought 1.1kg of root ginger, washed and peeled it, and put it through my slow juicer, which ground out about 500ml of pure ginger juice. The ginger cost 38zł, about £8. To this I added 320g of fine sugar and a tablespoon of brewer's yeast. Topped up to five litres in a small demijohn, with a air-trap neck to allow carbon dioxide out while keeping outside air from entering and turning it all into vinegar. For a week I watched the bubbles in the pipe - 25 a minute as fermentation peaked, then gradually down to 15, ten, five, three, finally one every two minutes... and a day later I filtered the brew and bottled the content, sealing each 500ml bottle with metal bottle tops. 

One bottle I opened on 4 June - on the hot afternoon following the pro-democracy march in Warsaw. The remaining nine were stored in the cool of the cellar. I checked up from time to time - all was good.

So my surprise - and regret - at seeing all of them blasted to smithereens - was intense. Questions - did they all explode around the same time (given that the bottles were identical, from the same factory, and the ginger beer was all from one batch)? Was it a chain reaction (probably not, as the cider, bottled in the same glass, standing on either side, was unscathed)? When did it happen?

Lessons learnt

Just because the fermentation has slowed down, it doesn't mean it has stopped. Don't be in a hurry to bottle. Take the demijohn into the cellar and leave it there for several more days before bottling. My first trial batch (one litre) went down very well with the neighbours (we drank it with Johnny Walker Red Label where the ginger beer was judged to be a far superior accompaniment than Coca-Cola); I suspect it could have done with being sweeter. The recipes call for 100ml of ginger juice to 100g of sugar per litre; I used just over 60g/litre of sugar. But more sugar = more fermentation = more time before it's safe to bottle. Once I have gotten over the loss of this batch, I shall buy more ginger and brew up some more ginger beer. 

Another lesson: beer bottles have an internal pressure resistance of between three to four atmospheres, (3 to 4 bar or around 44 to 59 lbs per square inch). This is the pressure associated with a well-inflated mountain bike tyre. Beer bottles are designed to cope with the carbonation pressure found in beers. Now, champagne bottles are designed to withstand higher pressures due to the higher levels of carbonation in sparkling wines. Champagne bottles are generally built to withstand pressures of 6 to 8 bar (88 to 118 lbs per square inch). That's the kind of pressure you'll find in a road-racing bicycle. 

So to break a beer bottle from within, the pressure of the ginger been must have been at least five times greater than atmospheric pressure, if not more. So - stronger bottles in future! Maybe plastic bottles for a second fermentation before final bottling.

UPDATE: 29 July. Second batch, also five litres, this time left to ferment in the demijohn for longer, more sugar, no yeast. Then I decanted the ginge beer into plastic one-litre bottles for a week; I'd check the pressure, unscrew cap for a second to release carbon dioxide build-up, then re-screw. After two weeks, I decanted the resultant ginger beer into glass bottles for further maturation.

This time five years ago:
My new used laptop
[Five years on, it's still fine - I'm writing on it right now! It was 18 months old when I bought it, (ex-leasing); since then it's had a new battery and a new set of keyboard stickers - original keyboard was German, on first set of stickers, the letters were rubbed off with alcohol - lockdown disinfectant. Otherwise, no faults whatsoever! So much for Student SGH's mockery... "Panie, Wieśwagen od starego Niemca, tyle co do kościoła i z powrotem jeżdżony"]

This time eight years ago:
Face to face with Mr Hare

This time ten years ago:
Central Warsaw vistas

This time 11 years ago:
Future of urban motoring?

This time 14 years ago:
On foot to Limanowa

This time 15 years ago:
Crumbling neo-classicism in Grabów

This time 16 years ago:
Bike ride into deepest Mazovia