Sopi Gletser 🇬🇧

This recipe is an attempt to make sopi using what’s available to me in the UK.

Sopi is an alcoholic spirit distilled from sageru, a fermented palm sap drink about the strength of beer (cf. tuak), and is produced in Maluku and other parts of eastern Indonesia. It may also go by the name of moke - as far as I can tell these are names for the same thing, though I’ve heard conflicting opinions as to whether it’s a different drink or not. It can be made from a few different types of palm, though from experience I’d say sopi from the aren palm (Arenga pinnata) is nicer and more common than that from the toddy palm (Borassus flabellifer).

Over the years I’ve brought a few bottles back to the UK and have enjoyed sharing those with friends, but flying all the way to Ambon isn’t exactly convenient when I’m in the mood for a glass so I thought it might be fun to try making it at home. But being a distilled drink made from palm sap, this presents a couple of problems in the UK:

• There’s no palms here
• Distilling equipment is illegal here

You can’t buy palm sap either, so this all might seem a bit of a non-starter. What you can find, however, is something very close to the sageru from which sopi is distilled. It turns out a very similar palm wine is made across west Africa, which you can find it imported in some African grocery stores in the UK. So let’s use this as a starting point. The one available near me is Nkulenu’s Palm Drink, which I’ve enjoyed a few times in the past.

The next issue is distilling. I have no equipment for this. But I do have a freezer, so taking inspiration from eisbock and applejack I thought I’d try the process of freeze distillation, where rather than boiling off and collecting the alcohol from some mixture (the wort), you instead freeze and remove the water, leaving a more concentrated solution behind. This is more correctly called fractional freezing, but whatever.

The danger of freeze distillation is that while traditional distillation, in the ideal limit, extracts the alcohol, freeze distillation simply removes the water. Everything else remains. The primary danger there is methanol, which no longer gets removed from the wort.

However, by using a commercially produced alcholic beverage as our wort, we have a built-in guarantee of the maximum methanol content. UK guidelines specify a maximum methanol content of 27 mg/L for beer. If we were to use such a beer as our wort, given a typical yield of 10% the original volume for this process, our final product would have a methanol content of 270 mg/L. Is this OK? Is that a lot? Well, UK laws set a maximum methanol content of 800 mg/L for brandy, for example, and EU laws list the maximum safe concentration as 4000 mg/L in a 40% ABV drink, so it looks like we should be fine. In fact, 270 mg/L looks to be about what you’d find in a commercial bottle of wine - and remember, the 27 mg/L beer used in our example would be unusually high in methanol, with most commercial drinks presumably well below this. See this table for a summary of methanol content in commercial alcholic beverages.

Having said all that though, I have no idea if this all pans out in the real world. I have done no testing to confirm this, so just be careful.

Anyway, here’s the recipe.

Recipe

Add the palm wine to a big plastic bottle, leaving room for the expansion of the ice.

Leave it in the freezer for a day.

Open the bottle and leave it upside-down in a container to catch the runoff until the ice looks almost white (~2 hours).

Discard the ice and repeat the process with the collected liquid until it no longer freezes (usually ~4 cycles).