Zinfandel - fermenting faster than expected

[MJD]

Hi all - hope your respective fermentations are going well. This is my first Zinfandel excursion and hoped you could provide some insight. My question is at the end, with details in the middle.

My prior experience with red varietals is all Willamette Valley Pinot and Cabernet. Every year, those fermentations went 1.5 - 2 weeks. ETA: my notes indicate ferm temps were 74-79 *F in those fermentations.

I'm on the east coast now and sourced the Zin from MM Grapes in Hartford on Saturday 09/14 and pitched D-254 on Sunday 09/15. SG at time of yeast pitch was 1.107, about 14.5% potential alcohol. I added Ferm K at the recommended rate prior to pitching. The must temperature at time of pitching was ~72 *F on Sunday. From Monday to Wednesday, the must temperature has been a constant 80 *F. My garage has been around 70 during the day and lower 60s at night.

In three days, the SG has dropped from 1.107 to 1.04! There are no bad smells or tastes.

Question 1: I would like a moderately structured (i.e., not Beaujolais, not super heavy either) wine at the end of this, if all goes well. If fermentation finishes this weekend, and it's time to press, would a 1 week fermentation give me a lighter wine than I'm hoping for, or would that be sufficient?

Question 2: If I try an extended maceration (say for 1 week), would "sealing" the top of the must with Saran Wrap or other plastic wrap work to isolate the must from too much oxygen, and would garage temps of ~60-70 *F be too hot?

Thanks for the help.

 

[Johnd]

Hi all - hope your respective fermentations are going well. This is my first Zinfandel excursion and hoped you could provide some insight. My question is at the end, with details in the middle.

My prior experience with red varietals is all Willamette Valley Pinot and Cabernet. Every year, those fermentations went 1.5 - 2 weeks.

I'm on the east coast now and sourced the Zin from MM Grapes in Hartford on Saturday 09/14 and pitched D-254 on Sunday 09/15. SG at time of yeast pitch was 1.107, about 14.5% potential alcohol. I added Ferm K at the recommended rate prior to pitching. The must temperature at time of pitching was ~72 *F on Sunday. From Monday to Wednesday, the must temperature has been a constant 80 *F. My garage has been around 70 during the day and lower 60s at night.

In three days, the SG has dropped from 1.107 to 1.04! There are no bad smells or tastes.

Question 1: I would like a moderately structured (i.e., not Beaujolais, not super heavy either) wine at the end of this, if all goes well. If fermentation finishes this weekend, and it's time to press, would a 1 week fermentation give me a lighter wine than I'm hoping for, or would that be sufficient?

Question 2: If I try an extended maceration (say for 1 week), would "sealing" the top of the must with Saran Wrap or other plastic wrap work to isolate the must from too much oxygen, and would garage temps of ~60-70 *F be too hot?

Thanks for the help.

Generally speaking, lighter wines are produced with lighter grapes and through winemaker options, enzymes, temps, pressing timing and force, etc.. I'd expect Zinfandel to produce a medium bodied wine, as a general expectation, if you don't try to push the extraction. Sample it as it goes along, deciding when you get what you want from a taste / body standpoint. Cooler, slower, fermentations will not have the extraction that hotter ones do, you're already a little on the warm side. The less time your wine spends in contact with the skins, the less the extraction, and therefore the "heaviness", so you could decide to press / separate your wine from the skins sooner rather than later. You could choose to utilize the free run juice only, or at least keep it separate from the press run juice. You can press very lightly or very heavily. All of these decisions give you the opportunity to craft your finished product, from where you are now.

Your ABV potential is something to consieder, at 14.5% +, be careful not to make too light of a wine, the alcohol may overpower the body. Had you started with a lower BRIX, you'd have a little more freedom with the balance of body / alcohol. Medium bodied Zinfandels are very good wines, one the first I made was as such, with fruit from Brehm, and I still enjoy it very much. Producers like Turley tend to make Zins with a full body and alcohol (over 15%), and they are very good too.

Allowing the wine to sit for an extra week on the skins will increase the body, and probably the complexity of the wine. Personally, in a primary fermenter, I'd be concerned about the amount of headspace beneath the plastic covering, but I'm no expert on extended maceration. Lots of the folks that have been performing extended maceration on their wines have been using Big Mouth fermenters with sealed and airlocked lids on them. Maybe someone else will chime in on this topic.

 

[MJD]

John, thanks for the detailed answer.

Matching the body of the wine to the ABV is one of my main concerns - with no experience with Zin, I'm not sure that a week of skin contact is going to get the extraction where it needs to be...but I also have no experience to support that concern. I've had 10-day fermentations that turned out fine. Is the difference between 7 and 10 days large? I don't have enough vintages behind me to know for sure. Perhaps a slightly hotter fermentation temperature will somewhat substitute for lesser skin contact time?

Regarding my current fermentation temperature - my research online gave a variety of answers, ranging from low 70s to high 80s as optimal. I have had success with Pinot (not that it's a similar grape) with both hot and cool fermentation temps, so I figured that high 70s/low 80s was pretty middle-of-the-road given the advice I saw online.

I'm going to drop a few frozen milk jugs (sanitized) into the must and see if it slows things down at all. I like your suggestion on the Big Mouth Bubblers, I have a few of those...may try doing a combo of that and some smaller buckets with plastic wrap pretty close to the must to minimize airspace - I only have 150 lbs of grapes.

I have a few days to ponder my next steps, anyways. Thanks for the response!

 

[BI81]

In regards to your first question I made a Contra Costa County Zinfandel last year, picked on 9/15 at 22.5 Brix, pitched the yeast (BM45 and RC212 in two separate brutes) on 9/16 at 72 degrees and was fermented to dry by 9/21 in both brutes, the fermentation temp got up to 85 degrees.

The wine is very light bodied, crisp and showcases some good lift compared to your typical Cali Zin, which I prefer, but it's lacking a bit in tannin and body which I'm assuming is due to the lack of skin/seed contact. Also, picking at a lower brix contributed to the body as well.

I've considered extended maceration, but have always worried about the risk of spoilage after fermentation has completed, so I'm interested to hear others thoughts on this.

One other item to consider if you plan on an extended maceration is to co-inoculate your MLF bacteria, I've never done this, but have read that this helps to reduce the risk of spoilage.

 

[CDrew]

You are unlikely to slow it down at this point. I'd just let it finish up and press, hoping for the best.

Extended maceration sounds risky to me. Going forward, as in next year, the enzyme treatment really increases body and color. THat's a safer bet than extending the maceration time.

 

[MJD]

I did use pectic enzyme during the 24 hour period between applying Kmeta and pitching yeast, so hopefully that bolsters extraction as well. Thanks for the responses!

 

[Johnd]

I did use pectic enzyme during the 24 hour period between applying Kmeta and pitching yeast, so hopefully that bolsters extraction as well. Thanks for the responses!

Next year, consider trying Lallzyme EX-V, it’s a stout extraction tool.

 

[CDrew]

Next year, consider trying Lallzyme EX-V, it’s a stout extraction tool.

I agree with this. Used it starting Saturday and by Sunday morning it already had markedly changed the wine and liquified the must. And the amount involved is tiny. I want to say I added 2.2 grams of the EX-V to 30 gallons of must. It's like instant color, and hopefully the flavor comes along too.

 

[MJD]

That sounds pretty potent! I'll be looking into it

 

[Johnd]

That sounds pretty potent! I'll be looking into it

It’s an enzyme that aids in the breakdown of the fruit, it does a very nice job. As @CDrew noted, it doesn’t take a lot, and you don’t want to use too much!

 

[MJD]

I've been using regular old pectic enzyme for the last 5 years, which calls for higher application rates than the Lallzyme EX-V. It seemed to do the job well, but I'll give the Lallzyme a shot since it sounds like a more concentrated substance.

The "regular" pectic enzyme did a heck of a job on a plum wine I did last month. 30 lbs of fruit, very coarsely chopped and of relatively firm flesh, was completely obliterated by the end of fermentation. There wasn't hardly anything left in the fermentation bag to squeeze!
It would be interesting to do a side by side with the Lallzyme and "regular" pectic enzyme, holding other variables as constant as possible, to see how they differ.

 

[CDrew]

It's my understanding that EX and EX-V have more enzymes than just pectinase. So they are more effective at breaking down the wall of the cells in the grape skin. I think that's whey they are so good at improving the color density of the wine.

Last year I used mostly EX, with good results, this year I'm all in on the EX-V. I don't want wines that will take 10 years to mature so not sure what I'll use in the end. Pressing this year's Syrah tonight after work and I'm looking forward to seeing what the EX-V brought to the new wine!

 

[MJD]

Well, it did end up slowing down a little bit with nighttime temps in the 40s Thurs-Saturday. We are on day 9 of the ferment and the hydrometer is saying SG is 1.000, although a moderate cap is still forming - likely the reading is now slightly off due to the current alcohol content.

We'll probably end up pressing tomorrow evening. The color extraction is most certainly there, and the body of the wine seems to indicate an adequate extraction at this point. We'll see!

 

[Johnd]

We are on day 9 of the ferment and the hydrometer is saying SG is 1.000, although a moderate cap is still forming - likely the reading is now slightly off due to the current alcohol content.

Not likely at all, the hydrometer is the tool you want to use when alcohol is present. The refractometer is the tool that yields distorted readings in the presence of alcohol.

 

[MJD]

Interesting, John - I calibrated it a few weeks ago for giggles and all was well.

It makes sense to me that for higher potential-ABV liquids as fermentation progresses and more alcohol becomes present, the increasing amount of alcohol will throw off the hydrometer reading as the amount of sugar progresses towards zero due to the delta between the density of alcohol and water. Has that not been your experience?

 

[Johnd]

Interesting, John - I calibrated it a few weeks ago for giggles and all was well.

It makes sense to me that for higher potential-ABV liquids as fermentation progresses and more alcohol becomes present, the increasing amount of alcohol will throw off the hydrometer reading as the amount of sugar progresses towards zero due to the delta between the density of alcohol and water. Has that not been your experience?

No, a hydrometer reads specific gravity, the SG of alcohol is less than 1.000, and water is 1.000, the presence of alcohol is why you get readings <1.000 when the sugar has been depleted. Many wine fermentations finish up at .990 when sugar is depleted, below the SG of water.......... The presence of alcohol may affect how low the SG gets when sugars are gone, but the readings are not "off".

 

[CDrew]

The hydrometer reads density only. So it doesn't matter if there is alcohol or there isn't. The reading is the reading. But alcohol is the reason that at the very end of fermentation, the SG is below 1.0.

The refractometer is thrown off by alcohol being present though if you know the amount of alcohol, you can correct the reading to give an approximation of the Brix.

It sounds like you're ready to press now.

 

[MJD]

Thanks for the clarification there - looks like my understanding was improperly framed.
Yeah, we are looking to press tomorrow evening. Looking forward to it.

 

[masic2000]

What would be the effect of not using enzymes during the fermentation process. Would performing an extended maceration not yield the same results thus minimizing the use of chemical additives?

 

[cmason1957]

What would be the effect of not using enzymes during the fermentation process. Would performing an extended maceration not yield the same results thus minimizing the use of chemical additives?

It might, but you would want to keep it cold during that extended maceration. There is far to much grapeskins, seeds, some stems to put it into a big mouth bubbler and keep it under airlock for an extended maceration. I certainly don't have anyplace to put a 30 gallon brute trash can, I think my 20 gallon could fit into my cold stabilization refrigerator. So chemical additives, that for the most part drop out of the solution are what I use.