2014 batch 3: Bochet (4) - Fermentation progress

Well, I felt that the fermentation did not really take off as I had hoped. I had to wait somewhat longer for the first bubble than I did with my previous mead. It did not really feel like the yeast got off to a good start. The bubbling rate also seem significantly slower. The reason could very well be that I prepared the activator straight honey, and poured the activator into the bochet must. Then the yeast cells had to get accustomed to the new environment first. The activator was at least very much alive when I poured it in. The liquid surface was vibrating due to tiny bubbles of CO2.

The development so far looks like this

date       pH     Oe   Additions

29/11   4.45   114   Nutrient pack 1

30/11   3.90   110   Nutrient pack 2

1/12     3.69   100   Nutrient pack 3

3/12     3.68     62   Nutrient pack 4

5/12        -        30   -

As the data shows the pH drops to 3.7 after two days, and stays stable. This pH drop is due to generation of CO2. It is also interesting that the initial drop in Oe is so slow the first 2 days. Only 14 degrees in 2 days. 

After adding nutrient pack 3, I figures I would skip a day before adding the last pack, to avoid to high concentration of nutrients. As it turned out, this was a good call. Two days after Oe had dropped 38 degree so the fermentation had gotten up to full speed at this point. I expect a maximum drop in Oe of 110 for this yeast, so I estimate that 60 degrees corresponds to approximately 50% of the fermentable sugar. Additions should not be done when the fermentation is past this point according to Ken Schramm. I assume he has done his share of trials and errors on this point so no need to repeat them :o)

In graph it looks like this: