Whole-Bunch Fermentation

[MOJO]

I just had the opportunity to obtain some late ripening Merlot and leapt at it. I was totally unprepared and I don't have time to find a destemmer. I really don't want to destem 400 kg (882lbs) by hand (I've done it before!!!)
So I am very interested in whole-bunch fermentation.
I'm not talking of carbonic maceration of whole destemmed berries.
I'm thinking of throwing the entire bunches with attached stems into the fermentation tank (perhaps I will get some carbonic maceration too).
I know this is done sometimes in commercial operations, but I am concerned about ending-up with a very high harsh tannin flavour.
PS I'm also considering not using sulphite, not innoculating and just allowing a wild fermentation.

Any advice?

 

[djrockinsteve]

I believe you would end up with a greater than normal tannin in the wine. Not sulfiting can be risky. I know some folks do not sulfite and everything comes out okay but many have had problems. It's your call

Don't know if freezing them and shaking them to have the grapes fall off would help. thats a lot of grapes. I understand.

 

[Sirs]

I'd at least crush them one way or another,I allow wild fermetation on all my wines but I'm not the norm...so to speak lol. If nothing else get a big drill and paint paddle to crush them you can get one at local hardware I'd think

 

[Wade E]

You will need to break them open to get good color and flavor extraction. If you do get a very high tannin extraction then you will need to do the egg white fining which Ive never done but Sirs here just did due to this exact problem and he is saying it worked and worked well so far. I know this is also done by highly respected wie makers like Daniel Pambianchi who does come on here from time to time and has written a few books on wine making.

 

[Rock]

Mojo we used to make wine this way with my father,like Wade said break them to give them a semi-crush.As you do punch downs you will want to take out as many of those jacks and stems as possible.We had a home made punch tool with spikes that would rip all those stems out as you stirred up your grapes.By the way what is your starting brixs?

 

[MOJO]

Hi guys. Apologies for the delay in replying - time differences etc. . .
I still have to complete the harvest this morning. DJRINSteve . . . freezing won't work for me. I just don't have anywhere that I could freeze that many grapes, but you're correct, if I'm taking chances with tannins I should exercise as much control as possible with yeasts, so perhaps I will Sulphite. Although "Sirs" has an adventurous streak started in me. Mm . . .
As a personal preference I tend not to do fining but in this instance I most definitely will consider it very favourably. And Rock, I was also thinking of hauling out as many stems as possible during the punch-downs! Hopefully I'll be able to get rid of many of them in the early stages and if Bachus is with me I may end up with subtle vegetal flavours rather than overwhelming tannins.
My starting balling (brix) was 25 (I need to confirm this today)

 

[bruno31]

Hi mojo,

Not destemming is a perfectly possible option. As usual, this will depend on the quality and maturity of your grapes: the more mature your grapes, the better will be your tannins.

As a matter of fact, systematic destemming is quite recent in the history of viniculture. Until the 70-80, even the most prestigious Bordeaux were made with entire grapes, until the fashion favored younger and easier-to-drink wines.

What you should know if you don't destem:

- color will be less intense (but more intense after several years!)
- tannin content will be higher, with more "hard" tannins (a controlled study has given a +27% increase in tannin content when not destemming)
- acidity will be lower
- alcohol content will be lower
- fermentation will be much easier (better oxygenation and naturally smoother temperature rises)

As you can see, there are several advantages, and the case for destemming is not as clear-cut as you could think from current practices.

However, it is clear that a wine made from full grapes will need more aging and maturing, and won't give you the "flashy" type of wine you see everywhere. When still young, the wine will clearly display less delicacy, but the reward after several years can be interesting.

You also need to be more careful with extraction, especially during the end of fermentation, when alcohol is present, and avoid too long macerations.

Overall, this can give you a more "classic" type of wine, which has its own charms. But if you want to enjoy your wine quickly, I would rather recommend CM.

 

[grapeman]

Whole cluster fermentation can be used in some grapes. The important thing is to have nice ripe grapes and stems. They won't contribute harsh tannins and vegetale character as badly. The stems should be nice and brown and taste nutty when bitten slightly. If they taste very green and harsh- it probably is not a good choice. Colors will be lighter. Fruit character may be better preserved. Press lightly after fermentation and avoud running them through any sort of mechanical process. Good luck with it. It can make a very nice early drinking wine if done right with the right grapes.

 

[MOJO]

Hi Bruno
Many thanks for your advice. I have 280 bottles of fruity Shiraz from last year to keep me occupied with "quick drinking". I'm really keen to try something different that may give me a wine with a bit of aging potential and possibly some interesting flavours. So I'm definitely going to try this. One question and then I'll tell you what I have in mind (I'm going to start in a few hours).
You suggest that I should be particularly careful toward the end of fermentation. Are you suggesting that I press the wine at or before Balling (Brix) reaches zero?
And should I press very lightly?

OK - this is my plan. I'm concerned about too many harsh tannins so I plan to press 30% of the harvest and use the free-run juice without any stems, seeds or skins. The complete lack of tannins from this fraction of the harvest will be compensated for by the remaining grapes which will go in whole with stems attached. I will just remove the main stems and leave the grapes attached to the lateral stems. How does that sound to you?

 

[MOJO]

Thanks Grapeman. After your advice I tasted the stems. Most of them are brown and nutty, but some are still green. The fruit is very nice. We got it just in time. I must add that harvesting was an added bonus and extra dimension to my winemaking experience. I feel very fortunate to have had this opportunity. We were able to select the best grapes in the field. As you will see in my reply to Bruno - I'm trying for a compromise. I don't necessarily want something too early-drinking. I'm looking for something with character and complex flavours that will age over time.
And I'm absolutely loving the steep learning curve and doing things differently from what I've done before. A bit of risk keeps it all exciting.
I like your comment about better preserved fruit flavours. Mmmmmmm.
Come over and have a bottle in 2 or 3 years time.

 

[Sirs]

I think as long as your equipment is good and clean you shouldn't run into any problems, I did a few batches of my muscadines stems and all and they did extremely good in fact those cleared better than the others. Only thing is the tannins are abit higher but nothing really bad in fact most are drinkable but you can tell they need to age.If you think the ABV will be lower than what you want take abit of the free run and make simple syrup will do fine....... don't be surprised that the wild yeast might get loud I've had some work really hard.

 

[bruno31]

I think the best is simply to taste every day and see when you want to press. Extraction depends on so many factors that there is no hard rule... If there is still sugar, you should of course be careful with the fact that tannins will be less perceptible...

When you like the tannin content, press gently, and put the juice apart. You will then decide if you incorporate it or not in the final wine. Keep in mind however that you need tannins for aging, so don't be too conservative!

Good luck!