Rum wash infection management

[JustinNZ]

G’day. I make SBB’s in 45L fermenters at 33deg C. I normally distil twice but sometimes do a 1.5.

Anyway, I fermented on a 3-week old rum trub and got an infection of some kind. It produced a delicious, tangy ferment and for me that’s a desirable thing. And the flavour came through strongly in the low wines. I feel that once aged on oak for a year or two it will make for the tasty rum I’m after.

But, only 40% of the unusual alcohols were produced (6L at 33% abv instead of 15L) meaning it had stalled or the infection ate at least half the sugars, or a combination of both - or something else. Not a desirable thing. I didn’t take an FG, D’oh! I’m a sour finger run it guy - but that would have been useful info.

I kept 10L of the Dunder for future purposes - ferment or spirit run.

I started a new wash on top of the infected trub but without the usual Dunder because I was concerned the combo of Dunder and infection might have stalled the ferment (and it’s alive and well).

I also kept 1.5L of the infected trub in a jar in my fridge.

And… mixed 15L of the tasty Dunder with water and 3L of molasses and some yeast. Nothing happened there. Not a surprise - just got a bit stupid. So I removed 20L of the currently infected and active ferment (was at 1.045) for a big 1.5 I’m doing and replaced it with the dead Dunder-water-mix to see if I can get some life out of it.

It’s been fun. From your experience, what’s the best way to keep decent levels of alcohol production WITH the infection? My reading here suggests adding infected wash to an almost finished wash is a winner. Will mean having dedicated infected fermenters though and serious-arsed cleaning between ferments. Thoughts?