2011 Ferments

[Cellar_Rat]

My northern traits will not allow me to purchase such, when I have a log pile.

I have a small (and rapidly deceasing ) heap of English oak logs.. I strip the bark off these, break them up into kindling and then blow the doors off my oven toasting them. Hmm me thinks the last bit needs updating...

[NorthernWiner]

I never gave it a thought - so the californians are still mid summer season - of course.

The thing to understand about California is that most of the vineyards are within 50 miles of the Pacific ocean, and that has a big influence on ripening. A lot of people think it's hot there (which it is once you get inland), but right on the coast it's somewhat coolish. It might get up to 32C during the day and then plunge down to 10C at night. The result is that it takes a long time for grapes to fully ripen.

The first time I visited San Francisco many years ago, it was August, but I was surprised at how cold it was. We all wore heavy jackets to take a catamaran cruise. Probably not much different than the weather you get in Wales - minus the rain.

[koomber]

Bottled the Vitners Reserve Cab Sauv from last year to free up a Carboy to rack all my other wines from this year (tardy, I know) would have bottled the merlot from last year too but this years merlot was honking of sulfur.

I administered some Scottish parenting (ie beating it with a short length of copper pipe) to the merlot and the smell has massively subsided. I'm going to leave it till tomorrow and see what it's like and then if it smells splash rack and repeat the beating.

The sangio was fine

[Cellar_Rat]

...this years merlot was honking of sulfur....

What do you think is the source/cause of this - I have never suffered this and I use no nutrient - I find it puzzling?

[koomber]

What do you think is the source/cause of this - I have never suffered this and I use no nutrient - I find it puzzling?

As do I. I think I may have over done the neutrient. Ah well. I guess some things you can just sprinkle on, other things you can't

[lockwood1956]

What yeast did you use Graham, some are more nutrient hungry than others, temps play a big part also

regards
Bob

[NorthernWiner]

... this years merlot was honking of sulfur.

I administered some Scottish parenting (ie beating it with a short length of copper pipe) to the merlot and the smell has massively subsided. I'm going to leave it till tomorrow and see what it's like and then if it smells splash rack and repeat the beating.

Graham, rather than beating up your wine with a copper pipe and oxygen, you might consider hitting it with a dose of copper sulphate solution. As you may be aware, CuSO4 will bind to H2S and cause it to precipitate out as an insoluble salt.

The most effective way to do this is make up an aqueous 1% solution of copper sulfate and use an eye dropper to add several drops to each carboy. The idea is to only use the minimum amount needed to rid it of the sewage smell, and no more. Just as an example, I had this problem with some under-ripe Petite Sirah this year. For 5 imperial gallons, I added 30 drops of the solution. That was all it took and it now the wine smells fresh and clean again.

I've found the best time to use this treatment is after pressing, when the wine is settling. Add the CuSO4, give it a stir (stirring up the lees on the bottom), and then use the old sniff test to see if the H2S has dissipated. Once it's abated, allow the wine to settle, and then rack it off the sediment into a clean container. This will leave the residual copper behind.

Please note... copper (as with most heavy metals) can have a deleterious effect on your internal organs if you injest too much. This is why it's important to use a very dilute 1% solution, and only the amount needed. BUT this is the way most wineries deal with the occasional H2S problem.

[Cellar_Rat]

... this is the way most wineries deal with the occasional H2S problem.

I have seen this is a few 'serious' books.
Have also heard of copper lips on the press and I have also heard of racking through small length of copper pipe - all very similar ideas.

I am really interested in why it happened though - it doesn't make sense to me. Would too much nitrogen cause it ? I have heard that the excessive use of nutirent can adversly affect to bouquet - but not quite this seriously

[Ted.B]

In the timeline posts red/white there is no mention of adding bentonite, should I have ?

[NorthernWiner]

I am really interested in why it happened though - it doesn't make sense to me. Would too much nitrogen cause it ? I have heard that the excessive use of nutirent can adversly affect to bouquet - but not quite this seriously

Quite the opposite, in fact. Too little nutrient is more often the cause than anything. All yeast produce H2S, however, it's not always detectable. When yeast are in a distressed state, due to improper nutrition, too high sugar, too high or too low temp, etc, that can cause increased levels.

According to the British Columbia Amateur Winemaking Association, here are some other common causes

1. Residual sulfur on the grapes as the result of a late spray for powdery mildew.
2. Some yeasts, such as Montrachet(UCD 522) and some strains of Steinberg, are known to produce higher levels of H2S.
3. Low nitrogen levels in the grapes which results in higher levels of H2S being produced by yeast cells (all yeasts produce some H2S that is dissipated during fermentation).

[lockwood1956]

In the timeline posts red/white there is no mention of adding bentonite, should I have ?

good spot Ted, i was sure i had added it to the timeline.

its an optional thing, i like to use it because i think it means the winew is less likely to throw a sediment in the bottle whilst ageing, and a vineyard owner/winemaker friend of mine claims it can drop some slight disease from white grapes (but only if it is slight)

regards
Bob

[lockwood1956]

I amended the timeline

[Ted.B]

I did add some after pressing as it seemed the right thing to do, had meant to ask the question at the time but as I was silly busy, kinda forgot.

[koomber]

Quite the opposite, in fact. Too little nutrient is more often the cause than anything. All yeast produce H2S, however, it's not always detectable. When yeast are in a distressed state, due to improper nutrition, too high sugar, too high or too low temp, etc, that can cause increased levels.

According to the British Columbia Amateur Winemaking Association, here are some other common causes

1. Residual sulfur on the grapes as the result of a late spray for powdery mildew.
2. Some yeasts, such as Montrachet(UCD 522) and some strains of Steinberg, are known to produce higher levels of H2S.
3. Low nitrogen levels in the grapes which results in higher levels of H2S being produced by yeast cells (all yeasts produce some H2S that is dissipated during fermentation).

Could someone give this man rep on my behalf? You saved my Merlot! I'd heard about the copper sulfate thing but didn't want to try it on acocunt of the toxicity issue. As it stands the smell is gone now! THANK YOU STEVE!

[NorthernWiner]

THANK YOU STEVE!

No prob at all. Glad to have helped.