Slow Then Stuck Sugar Wash

[Copper]

I don't know how some people can make such hard work of making a sugar wash, pick a Tried and True recipe, stick exactly to that recipe and keep it at the right temp, and it should work.

In your experience, this works fine. In my experience, sticking "exactly to that recipe" results every time in a stuck fermentation. Even my beer brews (targeting about 5% ABV) stall. I can purchase a box recipe, perform the brewing flawlessly according to kit instructions, and it will stall. Unless I do something different and deviate from the recipe, I get a sweet beer. The problem gets worse with high ABV sugar washes.

I started brewing in college and I'm over 50. During those decades, I've never had a gap without brewing something. I've been doing this for a long time.

My water has unusually low mineral content which creates two situations. First, the yeasts are starved from whatever minerals your water (and the original recipe author) provides naturally. My water apparently doesn't provide those nutrients naturally. Second, the fermentation quickly crashes after a huge takeoff and krausen - usually at the 24 hour mark - dropping about 20 SG points before stalling (assuming the starting SG is around 1.080 as most recipes target). I finally bought some pH strips and found the pH was lower than the paper strips could measure, probably around the 3.0 mark. This is data and decisions can be made using data. It's the same for beer, sake, and sugar washes. Basically, I'm brewing with distilled water.

Therefore, I must change something in the recipe or I get about 20 SG points of conversion and that's it.

I solved this by loading the wash with some extra minerals and a lot of chicken-feed oyster shells. I need about 1 liter of oyster shells to control 25 liters of wash. I don't get the "couple day" fermentation other people get. Mine take about 2 weeks to achieve 1.010 SG, presumably limited by the diffusion and conversion rate of the oyster shells. Because the conversion rate is so slow, the oyster shells can't keep up with the initial krausen. So even with oyster shells present, many of my fermentation stall in the first day or so. I need something faster than oyster shells but not as aggressive as powered calcium carbonate.

I am currently moving to crushed limestone (also it doesn't have the nasty smell of oyster shells). Crushed limestone has less surface area than oyster shells but probably better diffusion. I hope for a slightly better conversion rate than the oyster shells. I also think the yeast is being starved of certain minerals, which stresses them and causes excessive acid production during the krausen phase. I am working to solve this by a series of fermentations using distilled water with different mineral additions.

I do my fermentation in an insulated steel tank with a thermostat controller heater blanket that keeps the temperature within about 1 degree. Temperature isn't the problem. Chemistry is.

[bunny]

Calcium carbonate is not aggressive if you put it all in at the very start.
I experimented similarly to you with a 16lb sugar, 12g "distilled" water sugar wash.
In addition I added 1T DAP, 1 B complex and 1 B12 vitamin, a pinch of epsom salt and about 80-100g of CaCO3 powder. I pitched 1C Bakers yeast at around 95f.
Another 20-50g of CaCO3 would not hurt anything.
My water is fairly soft with 26grains of hardness.
Don't be afraid to run in the 90's f. I usually run upper 90's.
Don't worry about the starting pH!
The end pH result was around 4.0 after 24 hours.
Dry at 36 hours.

[shadylane]

Calcium carbonate is not aggressive if you put it all in at the very start.

Just a thought and I'm often wrong.
If using powdered CC it might be better to stir it in after the fermentation is started.
That way there's some acid to react with, otherwise the CC could fall to the bottom and just lay there.

Edited
Be ready for a possible foam up, add a little at a time while stirring .

[bunny]

Just a thought and I'm often wrong.
If using powdered CC it might be better to stir it in after the fermentation is started.
That way there's some acid to react with, otherwise the CC could fall to the bottom and just lay there.

Edited
Be ready for a possible foam up, add a little at a time while stirring .

After stirring and pitching my yeast most of my CaCO3 sinks right to the bottom. However there isn't anything else down there with it. It usually lands in a fairly even coating on the bottom. After 72 hours (when I remove the ferment and send it to the stripper) I usually find a teaspoon or two of CaCO3 beneath the fallen yeast. Presumably the rest has been destroyed by the CO2.

[Wildcats]

.
Shadys Sugar Shine is easy as pie if you FOLLOW the Tried and True.

[Saltbush Bill]

In your experience, this works fine. In my experience, sticking "exactly to that recipe" results every time in a stuck fermentation. Even my beer brews (targeting about 5% ABV) stall. I can purchase a box recipe, perform the brewing flawlessly according to kit instructions, and it will stall. Unless I do something different and deviate from the recipe, I get a sweet beer. The problem gets worse with high ABV sugar washes.

My water has unusually low mineral content which creates two situations. First, the yeasts are starved from whatever minerals your water (and the original recipe author) provides naturally. My water apparently doesn't provide those nutrients naturally.

Just for the record , I use rain water, it falls from the sky, hits my roof , runs into a very large poly tank and is stored there.
That is all that I have used for the entire time that Ive been in this hobby.
Everything I have read and researched says that rain water is very very low in minerals until it hits the ground and starts to soak into the earth.
In the time Ive been using rainwater, Ive made at least 4 different neutral sugar washes from the T&T section of the forum......each of those wash types has been fermented many times over.
100+ Generations of UJSSM one after the other, over a 11 year period
Lost count of the amount of Rum washes long ago.
Also, All Grain mashes /washes ferments , using malted grains as well as using using Yellow Lable yeast with unmalted grains.
I can think of two occasions in all of that time when a ferment failed to finish .......even those didn't fail completely.
I have no idea why you have so much trouble, but you seem to have more than most.
Can I ask what makes you want to make High ABV sugar washes to begin with.....they are only a road to bad booze.
It helps if you wash the shells first.

[Ben]

I also have incredibly soft water, and don't have trouble with ferments finishing. I adjust the chemistry these days, but when I first moved to this house and didn't know how soft it was I didn't have trouble.

Pitch the correct amount of yeast. Use a yeast that is suitable for your temperatures... if your ferment area is 68 a yeast designed to be run in the 80-90° range will not be happy. Use a yeast that can handle the alcohol level you are trying to get to.

Don't over salt (buffer, cacoX, whatever) -- the yeast MUST be able to drop the pH in order to reproduce.

Don't start at too high of gravity. If you are stalling, lower your SG on the next batch.

[Saltbush Bill]

Thank you for verification that its not just me Ben

[Copper]

Update.

I created 6 washes to measure results using various amounts of calcium carbonate, yeast inoculation, DAP, etc.

My test apparatus was an insulted kettle with thermocouple temperature instrumentation in a wine cellar with minimum ambient temperature fluctuations (19C). The kettle has 40 watts of heating blanket with power consumption monitor so net energy can be calculated to maintain constant 32C temperature during fermentation.

To summarize the result, the best fermentation was measured by:

- Net energy to maintain constant 32C temperature in 19C ambient (yeast activity is exothermic, causing the temperature to rise by itself)
- SG drop rate
- Weight drop (weight is lost by CO2 off-gassing)
- Calcium Carbonate consumption (measured by weight change of sacrificial limestone)

The first metric is healthy yeast converts sugar to alcohol exothermically. Pure glucose produces the highest exothermic density of 1.3kJ/g (see calculations below). To maintain 32C in 19C ambient, heat must be added by either the heater blanket or by yeast activity. The easiest way for me to measure yeast activity by comparing to how much energy (in watt-hours) the heater blanket requires to maintain constant temperature.

The second metric is unhealthy yeast cannot control pH and results in carbonate consumption. The healthiest fermentation will have the least carbonate weight loss.

The wash was sugar (sucrose) 1.080 SG without inversion and FermPro 921 yeast. The FSI-921 data sheet specifies 1g/gallon pitch. The yeast was rehydrated in 27C clean reverse-osmosis water for an hour then started with 1g/10mL DME (1.030 SG starter batch) and 1g/L BSG Fermax on a stir plate (forced fermentation) for 24 hours.

The best performance was achieved with the following, in order of importance. All fermentations performed at 32C.

- 3.5g/L DAP administered two-thirds during mixing process and remaining one-third added 24 hours later
- 0.5g/L of Zinc ions provided by zinc aceticum and gluconicum
- 0.1/L of pulverized multivitamin tablets (2 tablets per 20L)
- 6mg/L Potassium Metabisulfite (to remove average 3ppm chloramine from tap water)
- Pure O2 administered using diffuser stone in vortex during mixing process
- 0.5g/L BSG Fermax nutrient during mixing process
- 0.1g/L of Epsom salt (2g per 20L)

By a large margin, the DAP was the greatest contributor to performance. The BSG Fermax contains yeast hulls, which helps the yeast stay suspended for longer and might be optional. The zinc was provided by a popular over-the-counter cold remedy tablet. Basically, for my standard 20L batch, several tablespoons of DAP, one tablespoon Fermax, two pulverized multivitamins, one Ziacam tablet. Add another two tablespoons of DAP the next day. Done.

I found my optimal formulation uses a lot more DAP than the published recipes.

Using this formulation, I don’t need oyster shells, carbonate, etc. or at least greatly reduced. pH buffering and problem solved.

Reference
Glucose: C6H12O6 -> 2 C2H5OH + 2 CO2 + 235 kJ/mol
Sucrose: C12H22O11 + H2O -> 4 C2H5OH + 4 CO2 + 425 kJ/mol