Screw it, I'll get this analysis over with, so I can move on to the next labor intensive trial.
All washes in the trial had exactly 300 grams (200g/L) of table sugar, 30 grams of adjuncts (20 grams/L), water to bring the total volume to 1500 ml, and either a high level of nutrients (Fermaid K & DAP) at 285 ppm YAN, or a low level of nutrients at 95 ppm YAN. Ten grams of wine yeast were rehydrated with GoFerm protect, and pitched equally to the nine 1.75 liter fermenting bottles, resulting in a pitch of about .75 g/L. That is a pitch rate three times higher than the recommended 5 grams per 20 liters.
The result chart is totally confusing unless the trial is split into two groups. The first group is the five bottles all containing high levels of nutrients and plant-derived adjuncts.
As noted, they 'finished' (I arbitrarily chose an SG of 1.000 as the finish line) in the same order as their nitrogen content, as expected.
I was completely surprised by the performance of the other group of washes. I expected the soy protein (which has the highest nitrogen content of all trial adjuncts, at 1240 ppm) to be the top performer, but it did not even finish within a week.
At 148 hours, I added a crushed multi-vitamin to the sluggish soy protein ferment to see if it was a B-complex deficiency, and then a day and a half later, I added a couple grams of Fermaid K and DAP. You be the judge, but it looks to me like the vitamin helped and the extra nutrient didn't. I'll set that bottle aside to see where it goes.The low nutrient soy flour bottle was the last to finish, probably due to fact that it also may have suffered from a deficiency, probably vitamin as well. The nutritional yeast test came in second best, in spite of low added nutrients, probably because it is high protein to start with; and they load it up with B vitamins for the vegans to chow down. It came as a bit of a surprise to me until I looked at the nute info again and saw the extremely high vitamin B content.
And coming in first, and foaming all over my bathtub, was the bottle containing 15 grams of Marmite and 15 grams of soy flour (10g/L, each). That surprised me as well, because I thought the high salt content of that large of a Marmite addition would cause a huge osmotic shock to the yeast. Nah, they loved it. And it was a last minute substitution, to boot. At three in the morning, I discovered that I was out of the planned adjunct, tomato paste, so I just substituted a crazy mix of salty yeast extract and soy flour.
And what did we learn? You, probably nothing. Me, I am just coming out of the gate, so everything is a learning experience.
1. Fermaid K and DAP are more important than the amino acid proteins of plant-derived adjuncts, by far. However, neither are vigorous fermenters by themselves, a combination is essential.
2. Yeast based adjuncts are way more active than plant-based ones, even with respect to their relative nitrogen contents. Yeast seem to supply some essentials that plants tend to lack.
3. The cost of yeast extracts and inactivated yeast products limit their use as a sole adjunct.
Therefore, my next run will attempt to combine plant adjuncts with smaller amounts of expensive yeast adjuncts, while I experiment with producing my own yeast extracts using relatively inexpensive baker's yeast (and limiting the salt content). Anyone got any extra papain? It's the most effective protease for yeast, but Adolf's stopped putting it in their meat tenderizer.
Sex is like mowing my lawn. I hate it, but it's the only exercise I get.
wash trial two data.pdf
