What the …. @#%*!!?!? (Brewing in the Tropics – things you never thought you would have to think about)
So, like most brewers I learned to brew in a temperate climate (in Seattle in America’s NW corner). It may be damp but it is cool (or even cold) and when it is warm (the short period that it actually is warm) it is dry. But it is not so my friends when one lives in the tropics. It is ALWAYS warm and almost constantly damp. And these two things together can cause you some interesting problems for a brewer. For example I had bottom man-ways installed on all our fermentation vessels – they are safer, easier to access, have no cleaning shadow and are thus easier to keep clean – but because of the way they (necessarily) have to be made they are not insulated. In the north (where it is at least cool at night) the cold from the rest of the tank “telegraphs” down the stainless steal of the cone and keeps your yeast cool. In SE Asia, where it is about 32 degrees (94 F) most of days and nights the whole of the cone warms up and all your yeast sitting down in the bottom of the cone warms up as well - and then it dies. Bottom access manways are just not ideal for a tropical climate.
The heat; Yes, I know it sounds obvious but heat build up in an already hot climate can be a killer. The average ambient temperature in Singapore is about 33 degree C (about 92F). Add to that, heat absorbing brink or cement building or an un-insulated roof or poor ventilation, or steam leaks, or just a hot brew house full of boiling wort and the temperature can hit 38 degree C (around 102 F) and the humidity – that is a lot of sweating and at least one change of clothing a day (usually two).
Also one never thinks (or at least I never gave much thought to) malt vermin. In most temperate climate breweries their malt source is near by, deliveries are frequent, malt gets used fast and the temperature is cool (at least at nights). But did you know that there are weevil eggs in your malt (in all malt, it is already there) – the malt comes to you with the weevil eggs in it, and moth eggs too. Given enough time (about 2-3 months) at a warm temperature, these eggs will start to hatch and the resulting vermin will eat the insides out of your malt, leaving you with only brittle husks (which don’t really make a very tasty beer). There is not much you can do to combat this – except use the malt fast – very fast.
An additional worry is moldy malt. During the rainy season it can stay near 90% humidity for weeks on end and that can be enough to start mold growing (especially in an improperly sealed malt bag). Are if malt dust is left to settle or cling to almost any surface mold will grow on it. A frightening example of that is our grist bin. If left (without a water cleaning) for more than a few days the malt dust in our grist bin starts to mold and turn a wonderful color of hairy blue. So at the end of every week of brewing we wash down the grist in and let it air dry over the weekend. Temperate climate brewers never have to face such a potentially troublesome problem.
Surface Black Mold (which all but the luckiest brewers have to deal with in some area) in most climates is somewhat more aggressive and thus more of an issue. The warm and damp climate is perfect for it and it grows constantly, on everything – even on stainless steel. There is a fairly constant pressure washing, scrubbing and chemical abatement program. And that is just to keep it at bay.
These are a few of the unusual problems faced by breers in the tropics. If you brew in a temperate climate (much like the one I am returning to soon) you are luck and don't have to worry about t most of these issues - although then you may have freezing pipes or a zillion fruit flys or any number of other local problems. Brewers; just remeber - Luck you make beer for a living. A temporary solution to all life's little problems.