question about sediment

[Derek T.]

Monique...

[Monique Heinemans.]

Thanks Roy, we actually do have plans to go to Portugal in september this year, so I'll try if it works, hahaha.

, Monique.

[Roy Hersh]

Very cool. Is this your first time?

[Monique Heinemans.]

Yes, the first time, we've been to many other countries in Europe, as they're just around the corner, but somehow never to Portugal....
But I'm sure I'm going to enjoy it!!

Regards, Monique.

[Roy Hersh]

I for one, look forward to hearing back from you about your experience.

[Kent Benson]

I have some questions related to sediment. I’ll start with a couple assumptions which seem to be well accepted:

1) Vintage ports precipitate sediment because they are not fined, filtered, or cold-stabilized.

2) The precipitated sediment consists primarily of tartrates, anthocyanins, and tannins.

Here’s where my questions arise. Based upon the two assumptions above, it would seem logical to assume that filtration removes a significant portion of tannins and anthocyanins.

1) Is it primarily the removal of some tannins through filtering which makes LBV ports ready to drink much earlier than vintage ports, or is it that the grapes used in the LBV were not as concentrated and tannic to begin with? Or, is it because significant amounts of tannins precipitate during the longer cask aging?

2) Since anthocyanins are responsible for color, why does their partial removal from a LBV through filtering not result in significantly reduced color intensity, as their precipitation does in a vintage port?

3) Many table wines are now bottled without fining or filtration, yet they do not precipitate the volume of sediment precipitated by vintage port. Is this because the port grapes are so much more tannic to begin with and the lagar, foot treading process results in greater extraction?

4) If filtering removes tannins, does that mean filtered table wines, such as many Napa Cabernets, would be even more tannic if they were not filtered? Could such wines be considered as “de-tanninized”, since they have undergone a tannin adjustment?

[Andy Velebil]

I have some questions related to sediment. I’ll start with a couple assumptions which seem to be well accepted:

1) Vintage ports precipitate sediment because they are not fined, filtered, or cold-stabilized.

2) The precipitated sediment consists primarily of tartrates, anthocyanins, and tannins.

Here’s where my questions arise. Based upon the two assumptions above, it would seem logical to assume that filtration removes a significant portion of tannins and anthocyanins.

1) Is it primarily the removal of some tannins through filtering which makes LBV ports ready to drink much earlier than vintage ports, or is it that the grapes used in the LBV were not as concentrated and tannic to begin with? Or, is it because significant amounts of tannins precipitate during the longer cask aging?

2) Since anthocyanins are responsible for color, why does their partial removal from a LBV through filtering not result in significantly reduced color intensity, as their precipitation does in a vintage port?

3) Many table wines are now bottled without fining or filtration, yet they do not precipitate the volume of sediment precipitated by vintage port. Is this because the port grapes are so much more tannic to begin with and the lagar, foot treading process results in greater extraction?

4) If filtering removes tannins, does that mean filtered table wines, such as many Napa Cabernets, would be even more tannic if they were not filtered? Could such wines be considered as “de-tanninized”, since they have undergone a tannin adjustment?

Kent,

How'd I miss this post Welcome to the Forum and you've asked some really outstanding questions. Hopefully others will chime in with their thoughts first if not then maybe we can try and get some of the trade to answer them.

[Kent Benson]

Looks like no one's willing to tackle these questions.

[Roy Hersh]

Just timing, nothing more. Glad to give it a shot:

1) Is it primarily the removal of some tannins through filtering which makes LBV ports ready to drink much earlier than vintage ports, or is it that the grapes used in the LBV were not as concentrated and tannic to begin with? Or, is it because significant amounts of tannins precipitate during the longer cask aging?

It is mainly due to the mellowing of the tannins and the way the tannin chains behave through oxidation with the extra time in wood. The tannins largely are left in LBV's that are Unfiltered and even can be present in one's that ARE filtered. The filtration of Port is quite gentle depending on the producer. Some of the newest generation of mechanized filtration equipment is now employed in a variety of properties in the Douro. Lots of the tannins are not deprived of making their way into the bottles of LBV. Some of the tannins management takes place before the juice ever even gets into wood! The grapes used in LBV are every bit as tannic as VP grapes to begin with, unless there is an intentional plan to soften them during the crushing, de-stemming process and then how much pressure is applied with robotics or how long the grapes are tread.

2) Since anthocyanins are responsible for color, why does their partial removal from a LBV through filtering not result in significantly reduced color intensity, as their precipitation does in a vintage port?

Because it takes many years for the anthocyanins to precipitate out in a VP, it does not happen as much in the early years after bottling. I don't agree that the LBV filtration removes the anthocyanins to begin with. A small amount may be filtered, but lots of the color pigmentation happens early on and LBV fined and filtered, or not ... sees as dark a color in most cases as Vintage Ports.

3) Many table wines are now bottled without fining or filtration, yet they do not precipitate the volume of sediment precipitated by vintage port. Is this because the port grapes are so much more tannic to begin with and the lagar, foot treading process results in greater extraction?

The grapes are most often times from the same cultivars so it has nothing to do with Douro wine vs. Port, per se. Although there is some precipitation which happens early, it is minor compared to the extended aging of a Vintage Port. Open a 2000 Vintage Port which is now 11 years old and see how little sediment is visible in most cases. Then try 1991 and watch the difference an extra decade makes. Then open a 1977 and you'll see a pretty heavy crust compared to either of the younger VP's, although not too much more than the 1991. Port grapes are NOT more tannic than Douro wine grapes as mentioned. But tannin management is part of the winemaking process and some wines are intentionally made to be consumed upon popping the cork (Douro wines that is), while others are intentionally left to be more tannic so that they can cellar longer. Ultimately, this is as much a winemaker's decision as it is a natural process.

4) If filtering removes tannins, does that mean filtered table wines, such as many Napa Cabernets, would be even more tannic if they were not filtered? Could such wines be considered as “de-tanninized”, since they have undergone a tannin adjustment?

I don't know about "de-tanninized" however, yes, adjustments are, or can be made very simply. In fact, if need be in some regions of the world, tannins can be added, like an ingredient. Some appellations don't permit that while others allow for adjustments. It is all up to the style and image that is being portrayed, with intent by the winemaker. This can take place at the very beginning by de-stemming the clusters, vs. using whole cluster fermentations. The amount of time the juice remains on the less or mosto in Port terms, has a huge difference as lots of tannins are derived from the seeds and skins of the grape as well. Several other manipulations can be employed along the way, including the degree of fining and also filtration. But it is absolutely possible to do a filtration and leave tannins in the wine as the tannin chains get down to the molecular structure and can pass through IF the winemaker wants that to happen. Stripping back the tannins can certainly be achieved in wines that are supposed to be soft and immediately approachable, which are typically less expensive ... but even that, is not always the case.

I hope this helps. I'll let others have a chance and will try to get back here!

[Kent Benson]

Roy, thank you so much for taking the time to respond. Your comments were very helpful.

My questions were the result of taking some of the earlier comments to their logical conclusions, which created what I considered to be uncertain cause an effect relationships. I think it's pretty safe to say that a filtered LBV will throw less sediment than a vintage port from the same vintage, at virtually every stage of aging. The question is, why? If it is true that sediment consists partly of tannins, then, logically, either filtration must be removing a portion of the tannins from the LBV, or the LBV has less tannins to start with, due to winemaking techniques and the longer cask period. Your reply seems to suggest the latter.

That raises another question. If the differences in the volume of sediment of a filtered LBV versus a vintage port are primarily due to winemaking and different cask aging periods, why then is there a significant difference in the amount of sediment at all stages in an unfiltered LBV versus that of a filtered LBV?

The more fundamental question is what exactly is being removed in the process of filtering? If tannins are on the list, wouldn't one expect a filtered wine to be less tannic than an unfiltered wine and therefore be considered de-tanninized in much the same way that some wines are de-acidified by calcium carbonate?

[Roy Hersh]

That raises another question. If the differences in the volume of sediment of a filtered LBV versus a vintage port are primarily due to winemaking and different cask aging periods, why then is there a significant difference in the amount of sediment at all stages in an unfiltered LBV versus that of a filtered LBV?


Because a FILTERED LBV, intentionally removes ALL sediment that is in the casks prior to the time of bottling and an UNfiltered one, intentionally leaves all sediment in the Port. That way the filtered LBV will be best when pop n' pour (or decanting for slow oxidation) or for several weeks if stored properly once opened. In other words, the filtered LBV is intentionally stripped of its sediment.


The more fundamental question is what exactly is being removed in the process of filtering? If tannins are on the list, wouldn't one expect a filtered wine to be less tannic than an unfiltered wine and therefore be considered de-tanninized in much the same way that some wines are de-acidified by calcium carbonate?

Filtering basically removes the sediment which early on is made up of grape particulate (skins mostly but other parts too), dead yeast cells, proteins, stems, and even some tannins as well. Sediment may form as early as during the fermentation process. I am not contradicting my earlier statement by saying that some tannins can be part of the sediment, yet they don't have to be removed when the fining/filtration is done, albeit it is not possible to fully control what is extracted during these processes.

[Kent Benson]

Because a FILTERED LBV, intentionally removes ALL sediment that is in the casks prior to the time of bottling and an UNfiltered one, intentionally leaves all sediment in the Port. That way the filtered LBV will be best when pop n' pour (or decanting for slow oxidation) or for several weeks if stored properly once opened. In other words, the filtered LBV is intentionally stripped of its sediment.

Filtering basically removes the sediment which early on is made up of grape particulate (skins mostly but other parts too), dead yeast cells, proteins, stems, and even some tannins as well. Sediment may form as early as during the fermentation process. I am not contradicting my earlier statement by saying that some tannins can be part of the sediment, yet they don't have to be removed when the fining/filtration is done, albeit it is not possible to fully control what is extracted during these processes.

While I have no practical experience in winemaking, I've always been of the understanding that there are up to three basic steps to "cleaning up" a wine prior to bottling: 1) Racking; 2) Fining, and 3) Filtering. I've always assumed - perhaps erroneously - that virtually all red wines, including vintage ports, undergo some minimal racking to remove the wine from its gross lees and large particulate matter (the things you listed above as being removed by filtering). Fining is then employed to remove smaller particulate matter which is still somewhat suspended in solution, forcing it to settled to the bottom of the vessel. Finally, filtering removes the smallest of particals not yet removed by the previous two processes.

I'm uncertain as to whether or not most unfiltered LBVs and vintage ports are also unfined, since this is rarely, if ever, indicated on the label.

The original purpose of my entire line of questioning was to try and grapple with the ramifications of accepting the assertion made earlier in this thread that sediment consists of tannins, tartrates, and anthocyanins. While this may be true of aged vintage ports, it now seems probable to me that there are additional substances that precipitate out of solution or simply settle in unfiltered LBVs and vintage ports, especially in the early stages of aging. Otherwise, if filtering does not significantly reduce tannins, tartrates, and anthocyanins, as has been contended here, then there must be something else that explains the greater level of solids in young unfiltered LBVs and vintage ports as compared to young filtered LBVs. That something would seem to be the fine particulate matter still suspended in solution at the time of bottling.

[Andy Velebil]

I'm uncertain as to whether or not most unfiltered LBVs and vintage ports are also unfined, since this is rarely, if ever, indicated on the label.

The original purpose of my entire line of questioning was to try and grapple with the ramifications of accepting the assertion made earlier in this thread that sediment consists of tannins, tartrates, and anthocyanins. While this may be true of aged vintage ports, it now seems probable to me that there are additional substances that precipitate out of solution or simply settle in unfiltered LBVs and vintage ports, especially in the early stages of aging. Otherwise, if filtering does not significantly reduce tannins, tartrates, and anthocyanins, as has been contended here, then there must be something else that explains the greater level of solids in young unfiltered LBVs and vintage ports as compared to young filtered LBVs. That something would seem to be the fine particulate matter still suspended in solution at the time of bottling.

Generally speaking, no. VP's and Unfiltered LBV's are not fined. Part of fining is to force suspended molecules to bind together and fall to the bottom of the barrel/tank. Fining is done to prevent a wine appearing cloudy in bottle or in glass. VP and unfiltered LBV's being so dark don't need to worry about being perfectly clear. Port. especially LBV's, are typically in barrel longer than a dry wine is before being bottled and that also allows it longer to naturally clarify itself.

Basically a VP only gets a small amount of filtering to remove the skins, stems, seeds, and other large particles. All Port is "technically" filtered a little, but only to remove what I just mentioned. Otherwise we'd all be picking seeds and small stems out of our bottles. All that is used to filter is a metal cover with small slats cut in it that allow all but the large items mentioned to pass. I have a picture somewhere of that metal screen I'll try and find and post which would help explain a lot better. But it isn't anything like what a dry wine goes through, that I just want to be clear about.

As for the sediment, there was a good article in a past Newsletter about sediment and the overall answer was that a VP drops more sediment when it is young and that "dropping out" phase slows as it gets older. So think somewhere in the 15-20 year range where most of it drops out before it slows down. Of course that is a rough range and can vary depending on the quality of the VP to begin with. That sediment also changes as it gets older. Imperial evidence from my own drinking and from others is when young the sediment is more of a fine silty type which then changes to a thicker and denser type as it ages. Typically around the 25+ year mark you'll see it almost look like sheets of thick paper.

One thing not mentioned is cold stabilization (CS). CS is sometimes done to inexpensive Ports and some Filtered LBV's to make a more shelf stable product that all but guarantees it won't drop any sediment. it's difficult to make generalizations as procedures vary so much from Port producer to Port producer. But I hope this helps a little...and some great questions you've asked so far

(Forgive me for not providing links or pics right away, I'm not using my normal computer at the moment which has things saved already for quick reference)