Trying to Work With Grape Juice That is Amiss
TroubleShooting
John Regina — Vernon, Connecticut asks,
I have a Petite Sirah in secondary with the following characteristics:
- 23 L (6 gal.) of juice (2020 vintage) from the same supplier as I have used for 6 years
- Source of juice is California
- Brix: 21.1 (lowest I have ever had)
- pH: 4.1 (highest I have ever had)
- Titratable Acidity (TA): 2.5 g/L
- Free SO2: about 40 mg/L
- Temperature: 71 °F (22 °C)
I adjusted the TA by adding tartaric acid and achieved a TA of 7.5 g/L with a pH of 3.2. I added yeast (BM45) with nutrient. Fermentation proceeded normally. On day 7 when Brix was 2 I added the malolactic bacteria. On day 9, when Brix was 0.7 I racked the wine off the gross lees. A slow fermentation continued for the next 14 days. I did not take any measurements during this time. But on day 24 I did measure the following:
- Brix: 0.0
- pH: 3.2
- TA: >10 g/L (probably 12)
- Malolactic fermentation (MLF) is not completed
I didn’t measure FSO2 as the wine had only been racked once up to this time and had always been topped off. I racked the wine off the fine lees and that is where it sits today. The wine tastes very tart but there isn’t any noticeable odor. Apparently, what I thought was the slow tail end of fermentation was actually CO2 forming. Can you please advise me on any steps that I can take to salvage this wine? And what’s your best guess on how this came about in the first place?