Question:
Hi Guy: FWIW, I agree with Kirk here. I ferment kits at either a cool temperature (if I want to enhance fruitiness) or at ambient temperatures (if I want a little more complexity & aging [as in reds]). I never ferment kits/concentrates at temps above ambient (unless I add table grapes). -Ed — The Viticulture FAQ & Glossary – http://www.itsmysite.com/vitfaq "The discovery of a new vineyard does more for the happiness of mankind than the discovery of a new star." -Anthelme Brillat-Savarin Before you buy.
Response:
Just wondering as a newbie whether or not varying early (or late, I guess) fermentation temperatures can pose a benefit, ie: are there things to be gained from warm temp. fermentation and also cooler that could be gained from a bit of both, or is this too strenuous on the yeast? – Hide quoted text — Show quoted text – writes: Kirk, Would you say this also applies to kit wines? Guy — 80-85F is about the temperature at which I ferment most reds (actually, I prefer 85-90F). Especially with grapes from cooler climates. I can almost always tell the difference between a cool and warm fermented Cabernet from Finger Lakes. The cool fermented red is typically much more herbaceous than the warm fermented red (which tends to be fruitier). Kirk Guy, I’ve never made a wine kit so I can’t really answer your question, but if you don’t have skins to work with then I wouldn’t ferment warm. Kirk
Response:
Guy, Practically all red grapes have clear, colorless juice. The red pigment is in the grape skins. Red wines are made by fermenting the juice, pulp, and skins together. The red color is extracted from the skins during fermentation, and higher temperatures extract more color, etc. After several days of fermentation, the new red wine is then separated from the solids in a press. Besides color, many other materials are extracted from the skins during fermentation, and these materials contribute to the slight bitterness, astringency and body typical of red wines. White and blush wines are produced differently. They are made by crushing and then pressing the crushed fruit immediately. Only the juice is fermented. Low fermentation temperatures are used to preserve the fruit, and extraction is not an issue. Almost no skin contact occurs and little color, bitterness and astringency are extracted from the skins during crushing and pressing. This is why white wines taste differently than red wines even when the tasters eyes are closed. Concentrate and "juice" producers use several tricks to get red color into their products. Many even add red food dye. However, red colored wines made from concentrate or juice never have the same body, astringency, etc. as red wines made by fermenting the juice and skins together. Winemakers use the terms "white" and "red" in two different ways. Besides describing wine color, these terms are also used to indicate the way wines are fermented. For example, a "red" fermentation tank has an additional manway located at the bottom of the tank to make removing the solids easier. Regards, lum
– Hide quoted text — Show quoted text – Kirk, Would you say this also applies to kit wines? Guy — 80-85F is about the temperature at which I ferment most reds (actually, I prefer 85-90F). Especially with grapes from cooler climates. I can almost always tell the difference between a cool and warm fermented Cabernet from Finger Lakes. The cool fermented red is typically much more herbaceous than the warm fermented red (which tends to be fruitier). Kirk
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- Hide quoted text — Show quoted text – Kirk, Would you say this also applies to kit wines? Guy — 80-85F is about the temperature at which I ferment most reds (actually, I prefer 85-90F). Especially with grapes from cooler climates. I can almost always tell the difference between a cool and warm fermented Cabernet from Finger Lakes. The cool fermented red is typically much more herbaceous than the warm fermented red (which tends to be fruitier). Kirk
Guy, I’ve never made a wine kit so I can’t really answer your question, but if you don’t have skins to work with then I wouldn’t ferment warm. Kirk
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I seem to have a bad case of Hoof-in-mouth disease these days Guy. I meant to say….. when I ferment crushed grapes on the skins to make red wine, I prefer 80 – 85 degrees…. Many winemakers prefer short term temperatures as high as 90 plus degrees to extract color when fermenting on the skins. Sorry about the sloppy wording. Regards, lum
– Hide quoted text — Show quoted text – SNIP I prefer cold (50-55 F) fermentation temperatures for white and blush wines and medium (80 – 85 F) temperatures for red wines. SNIP Lum, the temp for the red seems high to me (from what I read, of course) Guy
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Kirk, Would you say this also applies to kit wines? Guy — – Hide quoted text — Show quoted text – 80-85F is about the temperature at which I ferment most reds (actually, I prefer 85-90F). Especially with grapes from cooler climates. I can almost always tell the difference between a cool and warm fermented Cabernet from Finger Lakes. The cool fermented red is typically much more herbaceous than the warm fermented red (which tends to be fruitier). Kirk
Response:
SNIP I prefer cold (50-55 F) fermentation temperatures for white and blush wines and medium (80 – 85 F) temperatures for red wines. SNIP Lum, the temp for the red seems high to me (from what I read, of course) Guy
80-85F is about the temperature at which I ferment most reds (actually, I prefer 85-90F). Especially with grapes from cooler climates. I can almost always tell the difference between a cool and warm fermented Cabernet from Finger Lakes. The cool fermented red is typically much more herbaceous than the warm fermented red (which tends to be fruitier). Kirk
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I strongly believe the only way to evaluate wine is by having several people taste the wine blind, and I think the reliability goes up as the square root of the number of people tasting. Regards, lum
This subject has come up several times, recently, around here lately, and after sampling several glasses, I’m ready to comment on it. My mentor rarely handed me a glass of wine that was pre-identified. The predjudgice (not even close enough for the spell checker!)of the mind can influence the experience to an incredible extent……thus the power of packaging and marketing. Whenever it gets close to bottling time, we rouse as many tasters as possible to get as many viewpoints as possible (learned from my mentor!). Like many things in life….it’s a numbers game. Who amongst us, home or professional, bottles wine for one person or even a limited profile of people. We bottle wine to satisfy the masses…whatever that number may be. So it’s important to have the opinion of the masses prior to bottling, and the less bias involved, the better. So many things influence how we perceive what’s placed in our mouths. (Ok:another subject) I enjoy an advantage that few ever do. I create the wine and then often have the chance to pour the wine for a wide range of people, and get to witness their reactions and hear their opinions. My first lesson was….don’t ever try to second guess or pre-judge a customer. They’ll trip you up every time. The other advantage I have is the market here in Missouri, which is probably as brod (and brodder….is this a word? how do you spell brod?) than any market in the world. We have customers from extremely sweet (8%+) to bone dry. So I have a full range of wines to satisfy everyone (hopefully). Where was I? Well, to sum it up. It’s quite interesting to see the preconceived notions that most people have about wine. There are a lot of people here in the mid-west US that prefer sweeter style wines, and most of them are somewhat embarrassed about it……because of a preconceived notion that a wine connoisseur is suppose to like bone dry wine. Who am I to say? I’m no one to say! I provide and sell them what they want. I had never enjoyed a sweet wine until I returned to Missouri and tasted some of the high quality Vignoles that’s now produced on a relatively large scale. Not that I consume a large amount….I eat much more steak than chocolate, but I still love a morsel now and again. Sorry….. hazard of making good wine running off at the keyboard. latron clyde
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SNIP I prefer cold (50-55 F) fermentation temperatures for white and blush wines and medium (80 – 85 F) temperatures for red wines. SNIP
Lum, the temp for the red seems high to me (from what I read, of course) Guy
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Back when I was still a San Franciscan, I went through a 2-year period where I added minute amounts glycerol to wines with short legs. I then noted a curious thing. Not a single wine I entered in competition with glycerol listed as a non-fermentable ingredient ever placed. Not one. This, I am convinced, was purely the result of bias on the part of the judges (who had the ingredients lists in front of them during judging), not taste. I say this because I could never get anyone to identify the two wines with glycerol added in 5-wine blind tastings–even a couple of judges were unable to identify them. Faced with such a bias, I stopped adding glycerol and began collecting ribbons once again. (Jack Keller, The Winemaking Home Page, http://www.geocities.com/NapaValley/1172/) Before you buy.
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- Hide quoted text — Show quoted text -Several years ago, a study was done at UC Davis* on how glycerol contributes to wine body and mouth feel in a white table wine, and the results were quite surprising. The study showed that the detectable sweetness of glycerol in wine is greater than 5 g/l, and there is no detectable contribution to body at the concentrations of glycerol normally found in table wines Oh well, so much for theory. Regards, lum * Noble, A.C. and Bursick, G.F., "The contribution of glycerol to perceived viscosity and sweetness in white wine," American Journal of Enology and Viticulture 35 (1984) 110.
Yes, I have read the results you quote….but what is your own experience? I have experimented with fermentation temperatures and gyycerol additions. My experience is that judious additions of glycerol can enhance wine quality. Rett
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Hi All, Glycerol is formed as a by-product of sugar fermentation, and it is one of the major higher alcohols found in wine. The amount of glycerol in wine depends on the amount of sugar fermented, the temperature of the fermentation, the strain of yeast, etc. More glycerol is formed at higher fermentation temperatures, so red wines generally contain more glycerol than white wines. Several studies show white and blush wines contain about 4 g/l of glycerol, and red wines contain about 6 g/l. Wines produced from Botrytised grapes often contain from 15 to 25 g/l. Here, the glycerol is synthesized by the mold, and it accumulates in the dried berries. Glycerol is very viscous, and some wine consumers believe it contributes to the "legs" observed on the vertical surfaces of wine glasses. In addition, glycerol tastes sweet. In taste tests, it appears to be about 70% as sweet as glucose. Because of the viscosity and the sweet taste, much popular home winemaking literature contains speculation that a high glycerol content is desirable because it contributes to wine body and mouth feel. Several years ago, a study was done at UC Davis* on how glycerol contributes to wine body and mouth feel in a white table wine, and the results were quite surprising. The study showed that the detectable sweetness of glycerol in wine is greater than 5 g/l, and there is no detectable contribution to body at the concentrations of glycerol normally found in table wines Oh well, so much for theory. Regards, lum * Noble, A.C. and Bursick, G.F., "The contribution of glycerol to perceived viscosity and sweetness in white wine," American Journal of Enology and Viticulture 35 (1984) 110.
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Yes, I have read the results you quote….but what is your own experience? I have experimented with fermentation temperatures and gyycerol additions. My experience is that judious additions of glycerol can enhance wine quality. Rett
Hi Rett, I prefer cold (50-55 F) fermentation temperatures for white and blush wines and medium (80 – 85 F) temperatures for red wines. By all means add glycerol if you feel it improves your wines. Our home winemaking group did some experiments with glycerol many years ago. A dozen people blind tasted both white and red wines containing various amounts of glycerol, and none of us could identify the wines containing small glycerol additions. We then increased the glycerol content until we could identify glycerol wines. But, most of us didn’t like the wines after the larger quantities of glycerol had been added. I strongly believe the only way to evaluate wine is by having several people taste the wine blind, and I think the reliability goes up as the square root of the number of people tasting. Regards, lum
Response:
Yes, I have read the results you quote….but what is your own experience? I have experimented with fermentation temperatures and gyycerol additions. My experience is that judious additions of glycerol can enhance wine quality.
My experience says "don’t do it". I tried it in my 1984 Pinot Noir, and didn’t like the results. I added about 50 ml per 60 gallons. The unadulterated Pinot Noir was better – and still is. Tom S
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