What causes my wine to be bitter?

[wineview]

try a fining with clear gelatin found in the grocery store follow package directions

I’ve used plain Knox gelatin for beer. Never occurred to me to use it in wine. When do you make that addition?

 

[heatherd]

Now I am reading Scott Labs literature. They sell products with PVPP and casein, both of which are used to remove bitter phenols: Polycacel and Polycel. My local wine supply shop has several Scott products including Tannin Riche and maybe they have Polycel. According to Scott, the Polycel settles after a week and can be racked or filtered. Adding tannin is the easiest first step, I think.

I buy their stuff online so that I can get all of their vast array of products, as my local store may have a few but not all: Home | Scott Laboratories

 

[heatherd]

I have looked into PVPP. I read that the wine should be filtered afterward and I am NOT excited about buying a filter pack.

Scott Labs website doesn't say anything about filtering, just to rack off the lees: Polycel (1kg) | Scott Laboratories

Fred or anyone that would like to share the cost of Tannin Riche, I’m game. It looks like ordering may be limited to large quantities. I’m intrigued by your findings. I hadn’t thought of finishing tannins.

It's not inexpensive at $153.00:
https://shop.scottlab.com/tannins/riche-500g-015962?returnurl=/tannins/?count=32

 

[VinesnBines]

It's not inexpensive at $153.00:

Actually it isn't terribly priced if I had 1000 gallons; I'm a little short this year.

 

[SLM]

I have 7 carboys of CS from last year's harvest. Tasted 2 days ago, so bitter I was ready to send them to the brandy factory. I came and read this thread for ideas.
Using what I had in stock I tried sugar, egg whites, tannin riche extra and tannin complex. Tannin complex wins so far. After one day that nasty bitterness is greatly reduced. Will continue trials but I have hopes this wine will be salvageable.

Anyone else have positive results?

 

[Timorthy]

I am starting to get organized for bottling 2020 Cab and Merlot and did a sampling of carboys with friends. I noticed a bitterness on the back end of my wines that I did not seem to notice before. I guess that bitterness comes from seed tanins. I am fermenting on the skins to 1.004 SG, so almost to dry. I have recently learned that some winemakers press as high as 10 Brix. So, that is a technique I am considering for future vintages. But also I have 3 ounces of French oak cubes per carboy. I also use enological tannins. Do those create bitterness?

It is true, seed tannins can create bitterness to the wine. You can use Malic Acid along with your tannins to reduce the seed tannins. You can also try using 100% oak barrel for all your ferments, or at least for the ferment of the red grapes. This will help the wine not to create too many tannins.

 

[Rice_Guy]

@SLM tannins are a family of chemicals (polyphenols) which are reactive, the end point of which is that they get big enough to fall out of solution and are a deposit on the bottom of the bottle.

Normal, is that the small molecules in ripe fruit have little flavor > these combine to produce a bitter molecule > the bitter molecules get larger and are precieved as astringent (mouth dehydrating/ protein complexing > growth continues till there aren’t enough hydrogen bonds to suspend the molecule in water.

Acid will normally magnify the flavor, as a test you can take 0.2 normal sodium hydroxide and bring the pH close to 7 or 6 and then taste the wine or juice to isolate the taste effect from the polyphenols and the acids.

Have you gone through the Scott Lab handbook to look at the choices? The bad news is that this is a family of molecules which are reactive and my answer at 36 months age may not be your answer at 15 months. Everything is taste to see what works.

 

[CDrew]

@Snafflebit - I just read through this thread, and wanted to offer up a guess at the original problem. It may be the oak cubes. 3oz per 5 gallons is a huge amount, even though MoreWine would have you believe it;s normal. Instead, during your next vintage, make some of your wine with no oak and taste that. Make some with say 1 oz per gallon and a little bit with your usual 3 oz. Then compare. Oak is kind of a mixed blessing in my view, You need a little, but not enough to consciously taste oak. There is always the danger you will make Chateau Pliewood.

The other thing, and it's just a thought, you went to a bladder press do I remember? That may help along with a crusher that has rubber rollers. My fermentations routinely get to 80F or more, so I don't think the heat has a lot to do with it. The one time I had wine that I got around to liking was a large vintage of Primitivo in 2018, And that one I oaked at 2.5oz per 5 gallons. I still have that wine hoping it will calm down, but at 4+ years I can still taste a bitter almost campfire quality that I do not like. It's gotten better, but at this rate I'll have to drink it in 2030.

And the last thing I would do is add even more tannin to the picture. Maybe an eggwhite fine, but adding more tannin just risks more bad tastes.

Good luck. Maybe update with how things turned out in the end?

 

[winemanden]

Not 100% sure, but I think the higher the acid, the more you notice the tannins, and the bitterness.

 

[winemaker81]

I just read through this thread, and wanted to offer up a guess at the original problem. It may be the oak cubes. 3oz per 5 gallons is a huge amount, even though MoreWine would have you believe it;s normal. Instead, during your next vintage, make some of your wine with no oak and taste that. Make some with say 1 oz per gallon and a little bit with your usual 3 oz. Then compare. Oak is kind of a mixed blessing in my view, You need a little, but not enough to consciously taste oak. There is always the danger you will make Chateau Pliewood.

CDrew is spot on -- 3 oz cubes in 5 gallons is a great way to make Chateau Pliewood (love that name, I'm keeping it!).

A heavy red can maybe handle 2 oz in 5 gallons, but I've dropped back to around 1-1/2 oz. Light reds get 1 oz, and if oaking a white, it gets 1/2 oz. When this year's wines go in barrel (54 liter / 14.25 US gallons), the Grenache is getting 3 oz and the Tempranillo is getting 4-1/2 oz.

Regarding your over-oaked wine -- try blending it into an unoaked wine in bench trials, e.g., 1/5, 1/4, or 1/3 Chateau Pliewood with other.

 

[Snafflebit]

@CDrew Good call on the oak cubes. I have not figured out what is a good level of oak. I did not notice oak on the 2020 Cab wine at 1 oz./5gal. Someone recommended bumping it up because...reasons! lol
I did not notice a Tempranillo level of astringency from oak tannin before adding finishing tannins. This year (2022) I have seperated out free run from press fraction and also targeted 1 oz. of oak per 5 gallons

Now, I have to say that since using the Tannin Riche, the bitterness is gone, or practically gone. However, the grippiness of this added tannin has "bloomed" after sitting in bottle for a couple of months. I performed bench trials and targeted the level I liked, but the astringency has overshot the desired target. This astringency is MUCH preferred to bitter wine. The wine is now drinkable at least, but a bit "angular" and age may polish off the edge.

@Rice_Guy I love the idea of neutralizing the acid in the sample to taste what the phenol flavors are adding directly!

 

[wineview]

@Snafflebit - I just read through this thread, and wanted to offer up a guess at the original problem. It may be the oak cubes. 3oz per 5 gallons is a huge amount, even though MoreWine would have you believe it;s normal. Instead, during your next vintage, make some of your wine with no oak and taste that. Make some with say 1 oz per gallon and a little bit with your usual 3 oz. Then compare. Oak is kind of a mixed blessing in my view, You need a little, but not enough to consciously taste oak. There is always the danger you will make Chateau Pliewood.

The other thing, and it's just a thought, you went to a bladder press do I remember? That may help along with a crusher that has rubber rollers. My fermentations routinely get to 80F or more, so I don't think the heat has a lot to do with it. The one time I had wine that I got around to liking was a large vintage of Primitivo in 2018, And that one I oaked at 2.5oz per 5 gallons. I still have that wine hoping it will calm down, but at 4+ years I can still taste a bitter almost campfire quality that I do not like. It's gotten better, but at this rate I'll have to drink it in 2030.

And the last thing I would do is add even more tannin to the picture. Maybe an eggwhite fine, but adding more tannin just risks more bad tastes.

Good luck. Maybe update with how things turned out in the end?

What are these egg whites you speak of.

 

[CDrew]

What are these egg whites you speak of.

These guys explain better than I could!

https://winemakermag.com/article/egg-white-fining

 

[CDrew]

@CDrew Good call on the oak cubes. I have not figured out what is a good level of oak. I did not notice oak on the 2020 Cab wine at 1 oz./5gal. Someone recommended bumping it up because...reasons! lol
I did not notice a Tempranillo level of astringency from oak tannin before adding finishing tannins. This year (2022) I have seperated out free run from press fraction and also targeted 1 oz. of oak per 5 gallons

Now, I have to say that since using the Tannin Riche, the bitterness is gone, or practically gone. However, the grippiness of this added tannin has "bloomed" after sitting in bottle for a couple of months. I performed bench trials and targeted the level I liked, but the astringency has overshot the desired target. This astringency is MUCH preferred to bitter wine. The wine is now drinkable at least, but a bit "angular" and age may polish off the edge.

@Rice_Guy I love the idea of neutralizing the acid in the sample to taste what the phenol flavors are adding directly!

I look at it like this. Grape wine from grapes, is good with NO OAK. So make sure you are improving it with oak, not using oak because you are " supposed to". I have come to max out at roughly 1 oz of cubes per 5 gallons of wine. Less is OK, you can always add more.

And for high powered wines like Syrah or Cabernet, they can take a bit more oak, but for less robust wines, less oak is better. Really, try it out. For less robust wines like Zinfandel or Primitivo less is more. Much less.

 

[Snafflebit]

I want to provide an update to this tannin thread.

Still loving the finishing tannins, but in my future wines I will go lighter on the addition. I have some 2020 wines that were a little lacking in flavor, which I attempted to fix with tannin. I added Tannin Riche after performing a bench test, but I think the flavor has grown a bit in bottle, or my memory has grown worse! Nevertheless, the vineyard owners say they and some friends enjoyed the wine. I can be quite hard on myself concerning wine quality but I think they were genuinely impressed. I am asking them to let all their friends try it and provide feedback.

I will have a 2021 bottling party soon and will have 2020 wines to taste and my notes to help me dial in future additions

 

[Snafflebit]

What are these egg whites you speak of.

A bit of trivia I just learned, the Bordeaux winemaking traditionally used lots of egg whites for fining, so naturally there would be lots of egg yolks to use. The dessert "Cannelés de Bordeaux" was invented by French nuns living in Bordeaux who were gifted the yolks. They look like a pain to make. I will just have to order some next time I travel.

https://chefiso.com/p/canneles-caneles-recipe/

 

[Snafflebit]

And for what it is worth, the bitterness of my 2020 wines is completely gone. Do I have the finishing tannins to thank? time? aeration? all of the above? who knows? Wine is such a mystery.

 

[winemaker81]

The dessert "Cannelés de Bordeaux" was invented by French nuns living in Bordeaux who were gifted the yolks. They look like a pain to make. I will just have to order some next time I travel.

Actually, they're easy to make. The one PITA is coating the inside of the molds with a mixture of butter and beeswax, it's a mess to clean up. I have both copper and silicone molds -- I like the copper better, but they're a LOT more expensive.

https://food.bkfazekas.com/2020/05/caneles-de-bordeaux/

 

[Snafflebit]

I want to follow up on this thread. I cracked open a bottle of my 2020 Cab tonight from the GW vineyard that up till now I expected to make better vinegar than wine. By gosh this stuff is tasty. Yes, it has the Tannin Riche added and I was not quite pleased with the result at the time, but it is integrating into the wine nicely and I do not detect any seed tannins. Many times have I sagely nodded my head at the newbie and said “give your wine time and it will improve” LOL physician heal thyself.

 

[tmcfadden932]

Cab needs to be ripe and the seeds completely brown with no green for the.tannins not to be bitter.