Friday, March 21, 2008

Past The Peak

Wednesday night when I checked the Pinot ferment there was no evidence of Kloeckera activity (no aroma of ethyl acetate) so I went forward with my plan to inoculate the must. I rehydrated 11 grams of RC212 yeast (25 g/hL) in a mix of 200 mL distilled water plus 13 grams of GoFerm nutrient (30 g/hL) at 104° F for 20 minutes.

I added a pinch of table sugar to proof the yeast prep. To my mild dismay the inoculum foamed only very slightly. I pitched it into the must anyway with punchdown number 7, though I would have been more sanguine if the inoculum had foamed extensively. After the punch the must was down to 23° Brix at 82° F; I moved the setpoints to 88° and 91° F.

When I checked the Pod early yesterday morning the must had overflowed slightly – perhaps a fistfull of pommace and 250 mL of liquid had gone over the side. It never ceases to amaze how much of a cleanup mess is created by such a small loss.

The Pod was reading 12° Brix at 91° F. For the first time in my WinePod experience, the cooling came on during punchdown #8. I moved the setpoints to 91° and 95° F. At the afternoon punchdown (#9) the must was reading 7° Brix at 92° F and the cooling did not come on until I dropped the setpoints to 83° and 86° F.

This morning at punch #10 the Pod was registering 4° Brix at 83° F, so according to plan I further lowered the setpoints to 78° and 81° F.

So I am past the most stressful (for me) part of the ferment. The yeast may be stressed a little – there has been a whiff of sulfide at the last couple of punchdowns. If it seems that the sulfide is still present at this afternoon's punch I will probably make a very small DAP add – maybe 0.1 g/L – even though I normally prefer not to add DAP so late in the ferment.

The only worry I have left is whether the ferment is going to stick or not. The slope of the sugar curve looks fine this morning – at this time the slope suggests that it is not going to stick – but the next data point is critical. I will be reassured if the reading this afternoon is between 3° and 2° Brix. If I see a reading of 1° Brix by noon on Saturday I will be confident.

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