This first year with an appreciable crop is still a modest harvest. We picked 54 lbs of grapes on September 27, 2007. I decided to stem and crush by hand, since the amount was so small. It still took my wife and me almost a day to take the berries off the stems. We'll find someone with a stemmer/crusher next year. All the grapes fit into about half of a seven-gallon bucket, which was fitted with a liquid airlock so that gasses could escape but nothing could get into the bucket. We squeezed the grapes by hand, leaving about 50% of the grapes whole. We put it in a lukewarm ice bath in the basement to keep it cool before we could add yeast and start fermenting. I gave Brian a 50ml sample that he analyzed at the winery.
Although we had a fair number of raisins, we also had a lot of fruit that apparently wasn't quite as ripe as we might have liked. The juice was 21.5 Brix (percent sugar), total acidity of .65g/100ml and a pH of 3.74. Not only did Brian talk me through all this, he also provided the yeast, nutrients and additives all measured out. We used
Before adding the yeast to the wine I put the container of must in a shower stall in the basement bathroom, and started up a little space heater. Brian later advised turning it off since the basement was cool, but just warm enough to be reasonable for fermentation (in the low 60's). On Saturday 9/29 Brian provided the ingredients listed above and I got to work. I had purchased the Winemaking Equipment Kit from the Home Brewery, which had most of what I needed. Another winemaker friend (named Allen) loaned me the excellent book From Vines to Wines and gave me some extra sanitizer solution already mixed. The procedure that Brian specified for starting fermentation (also described in Scott Labs "Fermentation Handbook") called for adding the tannin first, then getting one cup of pure water at 110 degrees F and adding the nutrient. After the solution cooled slightly to 104 degrees, add the yeast. After about 20min I started combining it with some of the must (the grape juice). The juice was at about 64 degrees and the yeast solution had cooled to about 80 degrees. You're supposed to add the yeast slowly to the must, to avoid shocking and killing it when there is a big temperature differential between the starter solution and the must. Over the next 30 minutes I slowly added a cup of must to the starter solution. That solution was then added to the bucket of must, along with the "Fermaid K". Twice a day I "punched down the cap", which means stirring the must and pushing the grapes that have risen to the surface down into the juice.
After the first day or two the yeast gets going and the little airlock passes a bubble about once a second. Once the yeast is added, you're supposed to test the percentage of sugar (Brix) once per day. But I was a little lazy about getting a graduated cylinder, finally making one from PVC pipe on 10/3. It's needed to contain the wine and the hydrometer used to test Brix. The specific gravity of the wine is measured by the hydrometer, and that's a proxy for the amount of sugar in the must. Fortunately, the yeast did its job and didn't die off prematurely, as apparently can happen at times. My Brix measurements were all done at about 6pm and were
Each time I measured the Brix I also tasted the must. Brian made a good point about learning how to taste what's going on, as well as measuring, since you can taste more things at once than you'll have time or money to measure (unless you have a big winery making a big batch where a few hundred dollars for testing is a nominal cost compared to the value of the wine).
The must started off as nice sweet grape juice before fermentation. Early on it's a little unpleasant, since I suppose I was tasting a lot of yeast. Gradually it gets the "bite" of alcohol and the unpleasant yeast tase disappears. At the end of primary fermentation it tastes like a sort of vacant, bad wine. The gases released by fermentation smell kind of like bread.
On 10/8 I filtered out the skins and seeds from the juice with a spaghetti strainer and some cheesecloth. I rinsed the 6 gallon carboy (glass jug) with with Campden sanitizer solution and rinsed it three times with water. Sad to say, the result of filtering the must was only about 1.5 gallons of proto-wine. Secondary fermentation occurred, with the airlock occasionally releasing a bubble. This is important since with all the empty space in the carboy, it has to fill up with carbon dioxide from fermentation in order to displace the oxygen which could cause growth of bad bacteria. Acetobacter is a typical problem.
I purchased a couple of gallon jugs and a half-gallon jug that I used to "rack" the wine, and contain it once secondary fermentation was over and the wine needs to be kept more strictly from exposure to air. I also got three stoppers and three airlocks, since apparently even when you think fermentation is done, it might start again just a little bit, and pop any tops or corks in place, which is also a reason for waiting a long time to bottle the wine.
Brian measured the residual sugar at 0.4%. Apparently 0.3% is the desired maximum, so he gave me a tiny bit of malolactic culture. After 2 days it bubbled a little bit. On Nov 1 he gave me some sulphur to stop the fermentation and kill any remaining bacteria. The concentration is 40ppm of KMBS (potassium meta-bisulfite), which is 0.3g for my 1 gallon jug and 0.15g for my 1/2 gallon. I dissolved each in 10ml of warm water and added it to the jugs.
I racked the wine again on Nov 11 which resulted in 1 gallon, 1 liter, and another 10 ounces I put in a beer bottle.
On March 6, 2008 I racked the wine again. The wine in the beer bottle smelled and tasted fine, despite having a bit of air in the bottle, so I was able to use it to top up the other larger bottles and make up for the wine lost in racking. I also gave Brian 2 50ml samples for analysis, since I need to know how much sulphur to add to preserve the wine.
Unfortunately, on March 11 Brian reported that there was no sulphur in the wine and that had likely resulted in acetobacter producing some vinegar. Some "volatile acidity" is ok, but this is over threshold. We'll add some more sulphur to prevent it from getting worse, but it's a signficant flaw. Apparently, the sulphur we added earlier in the process was completely taken up and dissipated in the wine. That can happen, and it's harder to get the concentrations right on small batches.
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