Friday morning I worried over whether or not the fermentation would stick. I got my answer Friday afternoon, where the must readings were 0° Brix at 79° F before punchdown #11. The graph above shows a clear inflection point from the morning reading to the afternoon.
This sort of curve inflection indicates a second yeast population picking up as the first population slows – I have observed this inflection before when re-inoculating a sticky ferm. It appears to me that the RC212 inoculum – added at 9.5 days – took a while to pick up, but did. I also noticed that the hints of sulfide aroma I had observed in the morning were completely gone, so I did not add any DAP after all.
Friday afternoon I lowered the setpoints again, to 74° and 77° F. I made only one punch (#12) on Saturday, where the readings were -2° Brix and 73° F. Once again I dropped the setpoints, to 68° and 71° F. I also put the lid on the Pod, since the fermentation is effectively complete.
At punch #13 today, the must read -3° Brix and 68° F. I made the final adjustment to the temperature setpoints, to 66° and 69° F, where they will stay through pressing.
I am still on track to press on Wednesday the 26th as I originally planned, after 14 punchdowns and 16 days of cuvaison. Yesterday I started prepping the barrel with the first fill, and today I gave it the second filling with hot water.