Influence of temp on extraction

[MOJO]

What is the relationship between temperature during primary fermentation of a red wine and extraction?
There seem to be two opinions:
1) A cool slow primary fermentation is best for colour and flavour extraction OR
2) Primary fermentation should reach between 80 deg F and 90 deg F (27 deg C - 32 deg C) for optimal extraction.

Which is correct?

Personally I prefer a cool slow primary fermentation but am interested in other opinions.

 

[surlees]

Both.

1) A cool slow primary fermentation is best for colour and flavour extraction

Best for white wines because it develops and retains aromas/bouquet.

2) Primary fermentation should reach between 80 deg F and 90 deg F (27 deg C - 32 deg C) for optimal extraction.

Best for red wines because red wines are fermented with the grape skins and the skins contain the anthocyanin (red color). The higher temps help in extracting the color.

Welcome to the forum!

Fred

 

[MOJO]

Thanks Fred
Both for the welcome and the advice.
My question referred specifically to reds. And I understand from your advice that reds must experience that temperature spike for colour extraction. However "high" temps are counter-intuitive for me, even for reds. I would prefer to achieve a long cold soak prior to primary fermentation in order to maximise colour extraction, and then follow with a long cool fermentation.
Anyway this is purely academic right now because yesterday my Shiraz peaked into the lower end of the temperature range we are discussing. But the debate is interesting and will help me NEXT year!

 

[joea132]

I remember reading something about extended maceration and how after a certain amount of time, you don't extract any more color so you are basically leaving your wine vulnerable for no gain in end product. I'll have to see if I can't find that time frame for you.

Also, I have heard some interesting facts about seed tannins and how an extended maceration can impart more of the harsh seed tannins in a wine. Tannins in the skins are water soluble but seed tannins dissolve in alcohol. Therefore with an extended maceration, you can run the risk of having an overly tannic product.

Food for thought

 

[surlees]

I would prefer to achieve a long cold soak prior to primary fermentation in order to maximise colour extraction, and then follow with a long cool fermentation

.
You are correct that a pre-fermentation cold soak helps to extract color, but the cold soak should be followed with fermentation temp in the 24C-30C range. Be careful above 30C because your yeast may not survive that high a temp.

 

[MOJO]

Thanks Joe. You are correct. I also read similar info. As I recall, by day four almost all available colour has been extracted and more significantly, colour intensity may even start to decrease after 8 days!!!!
(But tannin extraction just continues and results in accumulated tannins.)
This raises another question . . . Are these durations measured from harvest or from the start of fermentation?
If it is the former, then although a long cold maceration will assist in colour extraction this will be negated by the fact that cold maceration will extend skin contact time and therefore colour will be lost after the 8th day!

And thanks Surlees, I am very careful to keep the temp down in a healthy zone for the yeast, but if the info about allowing it to peak once above 28C, then the window is quite narrow. Anyway my Shiraz got up to 28C today and I've cooled it and am managing to keep it kust below. Fortunately we suddenly have nice cool weather here.

 

[Rock]

I remember reading something about extended maceration and how after a certain amount of time, you don't extract any more color so you are basically leaving your wine vulnerable for no gain in end product. I'll have to see if I can't find that time frame for you.

Also, I have heard some interesting facts about seed tannins and how an extended maceration can impart more of the harsh seed tannins in a wine. Tannins in the skins are water soluble but seed tannins dissolve in alcohol. Therefore with an extended maceration, you can run the risk of having an overly tannic product.

Food for thought

Yes,this is spot on.You would also want to do a delstage,for this reason.

 

[MOJO]

Hi Rock- I replied to your post but it appears that I sent my reply into cyberspace!
I think "Delestage" is an exciting challenge but I am hesitant for two reasons:
a) I run a very small traditional cellar and the modifications required plus the enormous amount of time and manual labour required would require me to stop my real job for the duration of primary fermentation,
b) Of course we want to extract maximal fruit and avoid EXCESSIVE tannins, but my concern is that in the pursuit of a quick drinking, soft, fruity wine we run the risk of producing wines that have too few tannins and are therefore out of balance, flabby and lack complexity. Wine making is a balancing act and wine appreciation is a personal taste, so I guess there are no hard-and-fast rules. And the beauty is that there is always room for experimentation and personal expression.

Having said all of that, you have gotten me planning to try modify my cellar a little in order to experiment with "delestage" next season!!!!!
Thanks for challenging my thinking.

 

[ibglowin]

Agree with everyone else that a red should get into the 27-30 degree C range for at least a day or two for good color extraction. Tannins will always settled down with time.

And welcome to the forums Mojo. From way across the pond!

 

[joea132]

Thanks Joe. You are correct. I also read similar info. As I recall, by day four almost all available colour has been extracted and more significantly, colour intensity may even start to decrease after 8 days!!!!
(But tannin extraction just continues and results in accumulated tannins.)
This raises another question . . . Are these durations measured from harvest or from the start of fermentation?

The 4 day timeframe was exactly what I read. As for the latter, I think extended maceration refers to the extra days after fermentation has completed, or the days you let it set on the skins after the point in which you would normally press. Does that make sense to you? If "maceration" refers to contact time between skins and juice, then "extended maceration" is time more than what you would normally do.

Let everybody know how things turn out too if you decide to experiement.

 

[Rock]

Hi Rock- I replied to your post but it appears that I sent my reply into cyberspace!
I think "Delestage" is an exciting challenge but I am hesitant for two reasons:
a) I run a very small traditional cellar and the modifications required plus the enormous amount of time and manual labour required would require me to stop my real job for the duration of primary fermentation,
b) Of course we want to extract maximal fruit and avoid EXCESSIVE tannins, but my concern is that in the pursuit of a quick drinking, soft, fruity wine we run the risk of producing wines that have too few tannins and are therefore out of balance, flabby and lack complexity. Wine making is a balancing act and wine appreciation is a personal taste, so I guess there are no hard-and-fast rules. And the beauty is that there is always room for experimentation and personal expression.

Having said all of that, you have gotten me planning to try modify my cellar a little in order to experiment with "delestage" next season!!!!!
Thanks for challenging my thinking.

Yes this a hobby,2009 my brothers and i crushed close to 4000lbs of grapes we had 10 huge primaries going at once.Lucky enough we work in the area and being self employed we would take turns to do punch downs in morning and lunch time night as well.I do loose a day of work here and their but i dont regret it.Last fall we only did half the amount.We drop what were doing when the grapes we want are in.I love this hobby!!!

 

[Luc]

I remember reading something about extended maceration and how after a certain amount of time, you don't extract any more color so you are basically leaving your wine vulnerable for no gain in end product. I'll have to see if I can't find that time frame for you.

Also, I have heard some interesting facts about seed tannins and how an extended maceration can impart more of the harsh seed tannins in a wine. Tannins in the skins are water soluble but seed tannins dissolve in alcohol. Therefore with an extended maceration, you can run the risk of having an overly tannic product.

Food for thought

Remember this can also be an advantage.

There are some low tannin grapes that actually need extended maceration.

So it all depends on the grape and the kind of wine you are making.


Luc

 

[MOJO]

Yes this a hobby,2009 my brothers and i crushed close to 4000lbs of grapes we had 10 huge primaries going at once.Lucky enough we work in the area and being self employed we would take turns to do punch downs in morning and lunch time night as well.I do loose a day of work here and their but i dont regret it.Last fall we only did half the amount.We drop what were doing when the grapes we want are in.I love this hobby!!

Rock, That sounds great. Did you do "delestage" on 4000lbs of grapes!!!
This sounds like a commercial operation rather than a hobby.
I met a guy who started as a garagiste' and eventually resigned from his job because he couldn't give his grapes the attention that they needed!!!

 

[MOJO]

Remember this can also be an advantage.

There are some low tannin grapes that actually need extended maceration.

So it all depends on the grape and the kind of wine you are making.


Luc

Luc - I think what you say is the essence of this discussion. As winemakers we have many "tools" or techniques that we can use in order to influence the taste of the final wine product. This is where the "art" of winemaking lies, instead of following a set recipe and doing just enough to prevent spoilage. We may chose to get involved in reducing tannins or we may decide to maximise tannins. This could be influenced by our personal taste or it may be influenced by the grapes with which we start. And I suppose as we gain knowledge and experience we have more "tools" with which to influence the outcome.

 

[Rock]

Yes this a hobby,2009 my brothers and i crushed close to 4000lbs of grapes we had 10 huge primaries going at once.Lucky enough we work in the area and being self employed we would take turns to do punch downs in morning and lunch time night as well.I do loose a day of work here and their but i dont regret it.Last fall we only did half the amount.We drop what were doing when the grapes we want are in.I love this hobby!!

Rock, That sounds great. Did you do "delestage" on 4000lbs of grapes!!!
This sounds like a commercial operation rather than a hobby.
I met a guy who started as a garagiste' and eventually resigned from his job because he couldn't give his grapes the attention that they needed!!!

No, only a 40 gallon batch.

 

[bruno31]

Thanks Joe. You are correct. I also read similar info. As I recall, by day four almost all available colour has been extracted and more significantly, colour intensity may even start to decrease after 8 days!!!!
(But tannin extraction just continues and results in accumulated tannins.)
This raises another question . . . Are these durations measured from harvest or from the start of fermentation?
If it is the former, then although a long cold maceration will assist in colour extraction this will be negated by the fact that cold maceration will extend skin contact time and therefore colour will be lost after the 8th day!

And thanks Surlees, I am very careful to keep the temp down in a healthy zone for the yeast, but if the info about allowing it to peak once above 28C, then the window is quite narrow. Anyway my Shiraz got up to 28C today and I've cooled it and am managing to keep it kust below. Fortunately we suddenly have nice cool weather here.

It is true that colour extraction is maximum after around a week, but colour won't decrease so much after that period, unless your grapes have a low anthocyanin content to begin with.

What I can say from my past experience as a professional winemaker (in the south of France, under Mediterranean climate) is that the more mature and concentrated your grape, the more you should extract - if you want to express the full potential of the grape.

If you want structure and aging potential, AND if your grape is perfectly ripe, you should definitely let the temperature reach 28-30C during fermentation for at least a few days, and extend maceration to several weeks.

As a matter of fact, even if few will recognize it, strong temperature control should be seen more as a "trick" to extract the best wine you can from grapes of questionable quality... Focus on the quality of the basic material, and you'll see that you'll have nothing to fear from high temperatures!

 

[joea132]

Welcome Bruno, you seem like you will have a lot to contribute.

 

[bruno31]

Thanks Joe, happy to be here