Results of Yeast Nutrient Comparative Experiment

[SaltUbar]

Problem;I fermented a 55lt wash using the WPOSW (see tried and true recipes I used this recipe exactly with the exception of the addition of one crushed Vitamin B complex tablet) after 5 days it got stuck. I attempted to restart the yeast by adding 1 tsp of DAP and 4 tsp of Sodium bicarbonate. The ferment started again and after 30 days I had 8.5% ABV as the remaining yeast was sluggish.

Thinking;
Problem of stuck fermentation was caused by the Ph of the wash getting to acidic and stopping the yeast from working. Test the solution by keep the yeast from stopping by lowering the Ph as the fermentation progresses.

Experiment;
On each day measure the Temp, SG and Ph then add 1 tsp of DAP (yeast nutrient) and 4 tsp of Sodium Carbonate (pool Ph increaser which is a stronger version of Sodium bicarbonate)

Results;
The experiment showed a significant improvement in yeast activity as shown by the very rapid reduction in Specific Gravity (SG) of the wash.

Summary;
Of the two batches the batch that had daily addition of Dap and Sodium Carbonate showed marked increase in yeast activity. This suggests that either the yeast in WPOSW is starved of nutrients or is inhibited by the highly acidic wash or both conditions are true. Delivering DAP and Sodium Carbonate daily improved the environment for the yeast which respond accordingly. Issues to investigate are

1. Does the addition of these daily chemicals make any change in the resulting distillate
2. Is there a need for both additives as this does not support the minimalist stance of the recipe
3. Would Calcium Carbonate be better additive than Sodium Carbonate.
4. Will these additive throughout the fermentation improve other yeast types

[Dnderhead]

white labs recommended: nutrients to be added it "steps" with high alcohol wash,,,,it recommends adding potassium carbonate to sugar wash at the beginning,,,
above 500 PPM sodium adversely affects yeast. (how much you'd need to add to git to this amount I have no idea..some cereals contain sodium adding more (sodium carbonate) mite "put it over the limit" or slow the wash down? as yeast can use both potassium and calcium that is what Id use.
(potassium carbonate is stronger and works quicker than calcium carbonate but is not for every one to handle)

[Dnderhead]

If I figured it right,, 4.5 oz of sodium carbonate per 5 gallon wash whould have adverse affect on yeast.

(don't quote me as I mite be wrong)

[Braz]

I will be watching the results of your experiment. One thing though, how will you know whether it is the addition of DAP or the PH adjustment that is affecting the fermentation rate?

At the very least you've inspired me to find and download a graph program. It is way cool to see the actual curve instead of just looking at numbers.

Braz

[rad14701]

At the very least you've inspired me to find and download a graph program. It is way cool to see the actual curve instead of just looking at numbers.

Most spreadsheet programs have graphing capabilities...

[Braz]

At the very least you've inspired me to find and download a graph program. It is way cool to see the actual curve instead of just looking at numbers.

Most spreadsheet programs have graphing capabilities...

Yea but the one in Excel sukz. This one is freeware and is pretty easy to use. http://www.padowan.dk/graph/" onclick="window.open(this.href);return false;" rel="nofollow Plus, it allows you to save a graph as a .jpg so I can post it here and bore people with details.

like this.



Braz

[airhill]

Was just wondering if you could graph or list the ph and temp readings readings over that period?

[SaltUbar]

Hi airhill

Was just wondering if you could graph or list the ph and temp readings readings over that period?

Unfortunately I have only got a Ph universal indicator so I can’t really measure Ph with any accuracy. All I know is that the Ph in my wash moves from 7 down to lower than 4.

My next purchase is a digital Ph meter so I can do exactly what you are looking for on a daily basis.

[Braz]

My next purchase is a digital Ph meter so I can do exactly what you are looking for on a daily basis.

I bought one of these last week. Working fine so far. At $22.95 it is not a huge investment.
http://cgi.ebay.com/Milwaukee-pH600-Dig ... 5885afcf1a" onclick="window.open(this.href);return false;" rel="nofollow

Braz

[airhill]

Should provide some very interesting information all put together, stuck ferments are a pain in the rear

[Dnderhead]

what you should do is 3 at once, one with DAP ,,one with calcium carbonate,, one with both. you keep chucking everything in it you don't know what is helping.

[ScottishBoy]

Not to sound too picky...but have you controlled for temperature variations as well?
Most of the problems I have had with washes have been temperature related.

[SaltUbar]

Hi Guys,

I have one batch now ready for stripping and I am going to start another this weekend. I will only add the Sodium Carbonate although I wanted to test that the addition did not adversely affect the end product before I ran to many batches as I am running 55lt at a time. My objective is to get the best neutral I can and if that means that it just takes a month to ferment so be it. If not fantastic, my turn around time can be reduced between batches.

As for temperature I am using an electric blanket on setting “2” during the whole ferment. This is resulting in a wash temperature on about 30 degrees C. Not sure about the night time temp as I only measure at about 8pm each night. Here in New Zealand the night time low is about 10 degrees C at the moment so I don’t think the wash temp will very much as I also insolate the barrel with a blanket. More importantly I do this the same way for all batches so it will not be a variation between batches contributing to a result difference.

Absolutely agree with doing three side by side batches but It costs about $100 per barrel here in NZ so I only have 2. There is no way I want to spring for another barrel plus a $80 Ph tester.

[SaltUbar]

Hi Guys,

Here is the comparison of the WPOSW with additions of Sodium Carbonate vs Calcium Carbonate. Same as above my standard wash is 55 litres’s using WPOSW (see tried and true section)

Note: On the Calcium Carbonate wash I delayed the addition of the first lot of DAP and CaCO3 by 12 hours to see if the addition was time sensitive. What I can see is a big impact on the slope of the AVB% line and a retardation of the fermentation.

My summary of this is:

1.That Sodium Carbonate (NaCO3) and Calcium Carbonate (CaCO3) have the same result

2.The timing of the additions is very important get the first lot added within the first 24 hours of pitching the yeast.

3.Testing of the toxicity to yeast of the Sodium (Na) at concentrations above 1.2g / litre (I would have added 20 teaspoons of Sodium Carbonate (4 tsp x 5 days) which should have been about half the max of 63g for my 55 litre wash) I found no impact of this on the yeast compared to using the Calcium Carbonate.

4.Ph stayed well in the 3 to 4 range for both types of additions and at 4 tsp per day there was no danger of making the wash basic (ph > 7) causing the ammonia and blue colouring.

[Dnderhead]

I fiend this very interesting. more so than witching a pot heating on a graft.

[airhill]

Although the're a lot of variables I find this fascinating also. Its rarely someone will document trials, and that should be applauded (should be a thumbs up icon).
Dolomite may be a goer for the buffering