Kieselsol and Chitosan Test results

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winemaker81

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Last fall I started a test where I bottled part of 2 batches without a fining agent, and treated the remainder of each batch with kieselsol & chitosan (K&C). Friday and Saturday nights we taste tested both batches, using both aerated and unaerated samples of both the fined and unfined wines.

The short answer is that for both wines, the use of K&C reduced the aroma significantly and introduced a bitter note into the taste. While the fined wines are perfectly fine to drink, especially when compared against each other, the difference is strongly noticeable.

If anyone is interested in my full test results, it's documented here:

https://wine.bkfazekas.com/kieselsol-and-chitosan-test-results/
Note -- I do no adverting on my web site nor do I collect personal formation. If you leave a comment on a post, I will have your email address, but I do not transmit this to third parties in any fashion.
 
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Last fall I started a test where I bottled part of 2 batches without a fining agent, and treated the remainder of each batch with kieselsol & chitosan (K&C). Friday and Saturday nights were taste tested both batches, using both aerated and unaerated samples of both the fined and unfined wines.

The short answer is that for both wines, the use of K&C reduced the aroma significantly and introduced a bitter note into the taste. While the fined wines are perfectly fine to drink, especially when compared against each other, the difference is strongly noticeable.

If anyone is interested in my full test results, it's documented here:

https://wine.bkfazekas.com/kieselsol-and-chitosan-test-results/
Note -- I do no adverting on my web site nor do I collect personal formation. If you leave a comment on a post, I will have your email address, but I do not transmit this to third parties in any fashion.
Nice experiment. I don't use fining agents so I definitely appreciate the time spent.

What I think would be an interesting test now is your numbered rankings. A blind taste test of the same 4 variables, but not as a comparison. Meaning a test to see if you can pick it up without a comparable. Would you rate the unfined a 95 and the fined a 93 if you tasted them at different times, or would you only note the differences as significant in a side by side comparison, and both rank a 95 standing alone.
 
I'm going to have a friend come over, and blind taste the wines. Same thing -- aerated and unaerated samples of fined and unfined Rhone, then do the same for the Super Tuscan. I'll be doing in blind as well. While I'm most interested in his feedback about sensory impressions, we'll be looking at ranking as well.
 
It is a noticeable change and very interesting read. You have given me something to think about when I start my Syrah this week.

My question would be after fermentation at .996 sg, rack into glass, Degas, add packet D (FWK) to protect from oxidation as it ages but do not put in clearing agents kieselsol & chitosan? Let it age a year? No other rackings are necessary until July 2024?
 
My question would be after fermentation at .996 sg, rack into glass, Degas, add packet D (FWK) to protect from oxidation as it ages but do not put in clearing agents kieselsol & chitosan? Let it age a year? No other rackings are necessary until July 2024?
I'd follow the FWK protocol for a 14 day fermentation, rack into a carboy. Dose with K-meta. Do not add packet D, as it's not necessary.

From here, 2 paths:

1. Bulk age 5 to 11 months, stirring periodically for a bâtonnage effect. Add K-meta every 3 to 6 months. If it's white and not backsweetened, shorter is fine. If it's going to be backsweetened, or if it's heavier red, age at least 9 months.

2. Let rest for 2 to 3 weeks, then rack off the sediment. Add K-meta every 3 to 6 months, following the plan for #1.
 
From here, 2 paths:

1. Bulk age 5 to 11 months, stirring periodically for a bâtonnage effect. Add K-meta every 3 to 6 months. If it's white and not backsweetened, shorter is fine. If it's going to be backsweetened, or if it's heavier red, age at least 9 months.

2. Let rest for 2 to 3 weeks, then rack off the sediment. Add K-meta every 3 to 6 months, following the plan for #1.

If not using the clearing agents, I'd be more inclined to let rest for 2-3 weeks and rack off the sediment ..... I do not care for particles in my wine. Guessing that day might come but its not here yet, in fact, I've been filtering my wines since Oct 2023 with my AIO wine pump. I've been reading threads or posts about batonnage and I'm sure it adds more body / flavor but I don't think its my thing right now.
 
I do not care for particles in my wine.
I wasn't clear. With bâtonnage the stirring is done early on. During the last few months the wine should rest undisturbed, so sediment will settle and you can rack off the sediment. The wine will be clear.

For barrels, I gently stir at monthly topup, as the evaporation has made room for safe stirring. In the past I let the wine settle the last 2 months before bottling -- at this time I've increased that to 4 months, which is still after the oak cubes I added (neutral barrels) are expended.
 
If not using the clearing agents, I'd be more inclined to let rest for 2-3 weeks and rack off the sediment ..... I do not care for particles in my wine. Guessing that day might come but its not here yet, in fact, I've been filtering my wines since Oct 2023 with my AIO wine pump. I've been reading threads or posts about batonnage and I'm sure it adds more body / flavor but I don't think its my thing right now.
Just to offer a little more confidence in breaking the rules! ;)

FWK probably has altogether different directions than my kits, but same idea I am sure. I follow the kit instructions 100% in primary. I add the oak, the bentonite, anything included other than choosing my own yeast. And I will chaptalize if I want a higher ABV. I like to be around 1.100 on average.

I rack to secondary when fermentation is cooling down, but still active. Somewhere around 1.010-1.000, and I rack with my AIO so I don't degas. There are no gross lees from a kit unless you add a skin pack, so If I rack a little sloppy I am not overly concerned, but a lot of the fine lees are still suspended at 1.010 so you will get decent sediment either way. That's it.. All done with kit instructions. I top up with whatever makes sense and in about 2 weeks when fermentation is complete, I add K-meta. Not the kit pack that includes sorbate, just K-meta. If it isn't required I don't add it, and if I was going to back sweeten I would add it at that point that I add sugar, because if you manage to make it to 8 months, the yeast is dead anyway.

I am doing a Sur Lie and battonage white, and I stir whenever I think of it. Once a week, maybe. I have read that Sur Lie is only notable in a white as all reds are aged on the lees. I have mentioned this a few times and no one has confirmed or denied. There is no hard rule. I don't stir my reds, but they all sit on the lees for the duration of bulk aging. I just racked at 7 months and bottled a batch I was intending to age longer, but I CAN'T stop making wine. I needed room, so I racked 3 gallons off the top and bottled, and racked the other 3 gallons to bulk age in a 3 gallon carboy. If you are worried about sediment in your wine you can rack 2 days before bottling to rack off of any sediment, and any small amount of lees transferred will fall out before you bottle and it is easy to get the last bottle off of anything that settles.

I think that is about it, other than I really like bottling half a batch to get it in the rotation and start tasting, while leaving enough aging to ensure I will get to see how it plays out in time. I don't bother with the 'utility' wines. The lower end kits that are just there to drink whenever, but the good kits, and I would put FWK in that category, get split, and I hide at least a bottle from each half in a secret stash to pull out in the years to come.
 
I think that is about it, other than I really like bottling half a batch to get it in the rotation and start tasting, while leaving enough aging to ensure I will get to see how it plays out in time. I don't bother with the 'utility' wines. The lower end kits that are just there to drink whenever, but the good kits, and I would put FWK in that category, get split, and I hide at least a bottle from each half in a secret stash to pull out in the years to come.

Thanks for the insight. I like what you are saying about splitting the batch and intend to do this tomorrow or Wednesday with a raspberry wine. I have several 3 gallon carboys for dessert wines so it would be easy enough to split. Drink 10 bottles this summer and bottle the rest in Sept/Oct.
 
I exclusively use chitosan and kieselsol for fining when I do fine and have never had any flavor or aroma degradation and never had any bitterness I only fine about 30% of my wines usually they sit long enough that they clear up naturally or are not full of sediment so I don’t have any reason to fine them. I’ve had wines with a single racking that had no sediment at all and were crystal clear.
 
I exclusively use chitosan and kieselsol for fining when I do fine and have never had any flavor or aroma degradation and never had any bitterness I only fine about 30% of my wines usually they sit long enough that they clear up naturally or are not full of sediment so I don’t have any reason to fine them. I’ve had wines with a single racking that had no sediment at all and were crystal clear.
In a few weeks I'll be in NVA (that's Northern Virginia AKA DC area) for a meetup with @mainshipfred, @VinesnBines, and about 8-10 other members and their spouses. I'm bringing bottles of the fined and unfined versions of my 2021 Super Tuscan and Rhone wines. I'm looking forward to a test among people I've not previously met in person.

My brother and I discussed the wines throughout our testing, and agreed upon the same results. My son tasted the wines and without any discussion from his elders, had the same feedback.

I have had a negative perception of kit wines regarding nose for a long time, and assumed it was a result of concentrate.

If you haven't taste tested fined vs unfined versions of the same wine, you may not recognize the difference. It's subtle, but distinct.
 
Well Bryan you convinced me. My wine comes out of the fermenter and sits a month, then is racked and sits for another month before it's bulk aged. Those 2 months should get most of the particles out. What's left should get picked up by the 1 micron filter.

+1 ... I'm going to conduct a similar experiment based off Bryans information. I have a FWK Syrah five days from finish fermenting (July 4th), and I intend to rack into glass, wait like you to rack again, add Kmeta and let sit for 10-11 months. The only change is at 10-11 months, I plan to split the batch into 3 gallon carboys and add K&C to one carboy and just filter the second 3 gallon carboy without K&C. Should give me an opportunity to taste Syrah with and without clearing agents that has been bulk aged for the same amount of time. Should know something in about a year! Bryan doesn't mention sorbate in his article, unless I missed it, so I'm not using it either. Guessing he's not back sweetening and he's bulk aging long enough sorbate isn't needed .... one less chemical.

Keep in mind I'm not expert here. I've got about 9 wines going plus what I've bottled in the past 4 months gives me more wine than I've ever in my life! lol Yes, 1 kit per year average to 9 in four months. Talk about jumping into winemaking with both feet.

I love it ..... gives us all something to talk about in a year.
 
Bryan doesn't mention sorbate in his article, unless I missed it, so I'm not using it either. Guessing he's not back sweetening and he's bulk aging long enough sorbate isn't needed .... one less chemical.
I make 1 or 2 carboys per year of white, the remainder is dry reds, so sorbate is used primarily for the rare fruit wines I make. I have some "finishing" packs in a drawer, which I dated with the month/year I got them. I probably need to bin most of them, as I toss 'em after 12-15 months.

I have some packets of K&C in the drawer as well. I need to check the shelf life on them. I am not completely discounting K&C, or any other fining agent, but in the future I'll use them only for situations where a wine won't clear.

Every choice we make has pros and cons. I can't say that I have hard rules on anything in winemaking. IME a situation may arise which will cause me to deviate from a hard rule, so I keep an open mind, balancing best practices I've learned with individual situations that arise because no two ferments are identical.

This makes it tough to give advice to beginners, since they need steps they can follow, but sometimes reality pushes along a different path. ;)
 
This entire thread makes me wonder if there would be a noticeable difference in the taste of a filtered vs unfiltered wine. I also use the AIO with a 5 micron polypropylene filter. The polypropylene is not supposed to affect taste but... this is an assumption without a study/comparison to verify.

Thanks for doing this Bryan. When you first mentioned doing this study, I was very interested to hear your results. My gut feeling was there would be a discernable difference in taste but was curious to know if it was negative. Sounds like that is the case. My winemaking timelines are 9 to 12 months so I forsee avoiding fining moving forward. I wish I would've known this about 2 weeks sooner as I just fined 18 gallons.
 
This entire thread makes me wonder if there would be a noticeable difference in the taste of a filtered vs unfiltered wine.
I recall an article in Wine Spectator, circa 1988-1990. The author recounted a discussion with one of the First Growth owners in Bordeaux. The author named a vintage in the late 70's where he told the owner that they started filtering their wine. The owner admitted he was correct. I've heard of other people whose palate was sensitive enough to pick out very subtle distinctions.

Is my palate good enough to pick out something like that? Hardly! But it's indicative that filtering affects the wine, as flavor and aroma are particles in the wine. Is it enough to matter for most of us? I can't say.

The issue is not just the composition of the filter, it's the action of the filter.

If you want an experiment, reserve a gallon from each batch, unfiltered, and taste test those 5 bottles against the filtered wine starting 6 months after bottling.

I'm not advocating not filtering. That's a personal choice. I would like to see folks making these simple tests and sharing their results, as it helps others forming their own opinions.
 
In my research I read that taste and color weren't affected until you filter below .5 (point 5) micron. At 1 micron the color I see in the filter is colored particulate. Even at 1 micron I still find a light dusting of particulate in the bottom of the carboys, so there is some very fine stuff in there.
 
I've been following this discussion with interest. I wonder if we focus too much on crystal-clear competition quality wines. The premise is that even a tiny bit of sediment in the bottle is unacceptable. It is mainly cultural conditioning that leads us to believe that any sediment at all is a flaw.

Maybe we should focus on more "traditional" wines with a tiny bit of sediment that have a great flavor. Are we making wine to please the wine snobs, or making wine with a fantastic flavor that we enjoy drinking with our friends? If it has an awesome flavor, who cares if there is a tiny bit of sediment? Just asking for a friend 😉
 
If you want an experiment, reserve a gallon from each batch, unfiltered, and taste test those 5 bottles against the filtered wine starting 6 months after bottling.

I'm not advocating not filtering. That's a personal choice. I would like to see folks making these simple tests and sharing their results, as it helps others forming their own opinions.

I'm definitely on board with running an experiment. Unfortunately, I'm approximately 1 year out from bottling my next batch. I'm all caught up with my wines except for the 18 gallons I just started that will be going into my recouped barrel after about 6 months aging in carboys. So yeah, I'll post back in about 1 year. 😆

Maybe someone else wouldn't mind picking up the torch and running an experiment sooner.

Any takers???
 

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