The link below is to a set of documents put together by the kind people at Iowa State University. They have compiled information from different sources on all grapevines that are generally considered to be cold hardy. Very helpful information for the grape grower and the wine maker.
http://viticulture.hort.iastate.edu/cultivars/cultivars.html
I racked the Frontenac tonight and have to say I’m very happy with the flavor and body of this young wine. I used lightly toasted oak chips and they did their job just fine. Still a slight acid bite, but very workable. and a nice oaky feel/taste. Here are the numbers on it:
SG: 0.993
Brix: 7%
Alc: 11.1%
Res Sugar: 19 g/L
I pressed and racked the wine to secondaries tonight. Everything looked, smelled and tasted great. I am especially interested in the Prairie Star wine – it smells awesome. I only wish I had had more PS grapes. The Brix tested out at 8%. The Frontenac is coming along well too. I can taste the acid, but not nearly like my first Frontenac batch a couple years ago. I think with some aging and oaking both of these wines should turn out fine. The Frontenac Brix tested at 7% tonight.
Tonight I took a few measurements, removed the stems from the Frontenacs and pitched the yeast in both batches. The readings I got from both types of grapes:
Brix – Frontenc, 20.4 and Prairie Star, 19.8
SG – Frontenac, 1.087 and Prairie Star, 1.082
TA – Frontenac, .85 and Prairie Star, .6
pH – Frontenac, 3.6 and Prairie Star, 3.8
After taking the readings, I added yeast nutrient and then rehydrated the yeast for about 15 minutes before adding it to the must. I used Lalvin 71B-1122 for both batches. One of the reasons I chose this yeast was for it’s ability to remove up to 40% of the malic acid from fermenting wine – this should help keep the acid under control in the Frontenac must.
With last night’s heavy frost in my area, I decided to harvest the Frontenac and Prairie Star grapes this morning. The temps were in the upper 20s (F). All told, I picked 22 lbs of Frontenac and 8 lbs of Prairie Star grapes (one vine). Earlier I had picked 14 lbs of Valiant grapes. I spent some time before work sorting, crushing and sulfiting. The Frontenac went into my larger primary and the Prairie Star into a smaller backup primary. I covered the primaries and will let them sit until this evening.