by nuddy » Thu Jul 26, 2018 8:09 pm
Gday AD's
I've got a bad case of unfermentable rum wash.
The wash in question is now 11 days old and has barely drop a single SG point.
I've tried an vast array of techniques and experiments to get the damm thing chugging along, all to no avail. Let me run you through this character building 11 days.
15/7/18: The1st generation of a wild yeast rum experiment had just finished fermenting and been put through the still so naturally I got stuck into creating the wash for the 2nd gen.
In a 60L fermenting vessel the following was added:
9kg of bundy refinery molasses (ferm sugars of 5kg) was added with
2kg raw sugar
Onto this 6.5L of hot dunder from the 1st generation was added and mixed thoroughly with a stainless steel mash paddle.
4g DAP and 4.1g Fermaid A added along with hot and cold tap water to get it to 34L mark. I don't remember the temperature at this point but I think it was around the 35 C-40 C range.
8L of cold tap water mixed with the yeast trub/bed from gen 1 was then added and mixed thoroughly.
Starting figures for start ya bastard rum.
Temp corrected S.G: 1.100
temp: 30.0 C
pH 5.6
This was temp controlled to 30.0 C by an aquarium heater running off an ink bird controller with the temp probe strapped to the outside of the fermenter buried under a sacrificed stubbie holder to insulate it. 2 layers of towels were wrapped around fermenter to insulate.
16/7/18 - 24hrs later no airlock activity, opened lid no visible signs of fermenting taking hold, pH 4.5, 3 heaped tsp of calcium carbonate added to bump pH back up.
50ml of gen 1 wild yeast slurry warmed slowly in a bain marie style bath of warm water to 28.6 C then pitched into fermenter.
17/7/18 - 24hrs laters, ferm temp 29.2 C, veryyy slow airlock activity 1 bubble every 1-2 mins,
18/7/18- 24hrs laters measurements taken, temp corrected S.G 1.098, temp 26.7 C, pH 4.1
2L was drawn off fermenter and diluted to 3.27L in a 5L demijohn for a S.G of 1.060 to see if lowering S.G would relieve osmotic pressure of yeast and fire up fermentation.
21/7/18- 72hrs later, 80g of dried bakers yeast pitched into now 40L of rum wash.
3.27L lower S.G experiment was heated slowly over stove, had 8g of bakers yeast hydrated and pitched into it along with 2 tsp of calcium carbonate, pH was raised to 4.4, temp 33.0C, SG 1.059
22/7/18- 24hrs later, 40L wash measurements taken, pH 4.1, S.G 1.090, temp 22.0C, 7 tsp calcium carbonate added, then whole wash was diluted with 8.2L filtered tap water to S.G of 1.076, temp 26.0 C, additional bakers yeast pitched onto surface of wash.
3.27L experiment slowly chugging away.
24/7/18- 48hrs later, now 48.2L rum wash now, pH 4.0, temp 28.0C at bottom of wash, 32.0C at surface of wash, S.G 1.070.
3.27L experiment, pH 4.3, temp 18.0C, S.G 1.030, finalllllly somethings fermenting. I then dumped this 3.27L of actively fermenting wash back into the 48.2L of non fermenting rum wash to try get it kicking over.
25/7/18 - 24hrs later, no ferment taken hold, 20g bakers yeast hydrated in warm water with 3 tsp sugar for 25mins, bakers yeast went nuts and was added to approx 52L unfermenting rum wash.
26/7/18 - 24hrs later, S.G 1.070, not moved a single S.G.
I'm at a loss as to why this dammmm wash wont ferment out.
It's got 24hrs before I dump it. Anyone got any ideas on whats going on?