Old thread, but I got this brewing. It takes way more work than brewing beer for (likely) worse results, so I am just doing it for vanity. Unless you can get a syrup or wort from a friend don't bother. I can see it working as an ingredient similar to molasses though.
Carobs are actually somewhat common in some rural areas. I never saw it used for brewing, but they do make syrup out of it. There are different processes. I am documenting how some people do it. They aren't scientists so it is far from perfect.
The method to extract sugar:
Break carobs by hand and/or hammers. Pods, skin, everything goes into a barrel.
Soak them up in room temperature water. Just enough water to get all of it completely wet. I suspect mashing with warm water would work better, but this is how they do it. I am just documenting the process unchanged.
Soak them for 12 hours.
Filter the remaining liquid so you end up with a clear liquid. Throw away the pods.
Boil this liquid until you get the consistency you need. They boil it with wood for half a day in huge pots to get less than 10 lbs of very thick syrup per barrel of unfiltered water-carob mix. It looks almost same as light malt extract.
They don't add anything else to it. This is all. No added sugars, no sulphur.
I made a 15°P solution and pitched a 12oz bottle of yeast (Whitbread, S-04). It looks same as a porter stout, black.
The fermentation had no issues at all. It worked the same way it would work with wort. Same high krausen, same lag time. In hindsight I didn't need this much yeast, I just didn't think it would work as well as wort would. I half-expected the yeast to take a long time and act similar to making cider.
Took 4 days to ferment most of it at 70F. I will cold crash and let it settle a bit before I bottle.
