When to do the second racking?

Following “When do I do my first racking?” the next common question is “When do I do my second racking?” Following are my thoughts on the subject.

The main purpose of the second racking is to remove the gross lees, and up until recently I thought I knew the answer. However, recent common practices make me question that. Before we get into that, what are gross lees?

Definitions

Gross lees is the fine fruit pulp particles that are in suspension following pressing. I use the term “fruit pulp” as gross lees initially exist in all wines, regardless of type.

In contrast, fine lees are expended yeast hulls, and it’s fine to leave this in the wine. The practice of “sur lie” is to age wine on the fine lees. This is normally done with white wines to produce creamier, richer, fuller-bodied wine with greater depth and complexity of flavor, but can be practiced with red and fruit wines. Bâtonnage is the practice of stirring the fine lees back into suspension, to increase contact with the wine. [I’m not going into detail on this subject, but merely provided an explanation as folks will wonder.]

Note: pomace is the skin, pulp, and seeds leftover after a wine is pressed.

From what I’ve read, most of the gross lees drops within 24 to 48 hours of the end of fermentation, forming a potentially thick layer. From a human eye POV, it doesn’t look much different from fine lees, so I assume the difference is noted more under a microscope, e.g., 1 micron is a lot different from 100 microns. [This is illustration; I have no idea what the particles sizes are.]

I notice the gross lees is more “sticky” or “gummy” acting — when cleaning the carboy I notice a significant difference in the way the first sediment moves versus subsequent sediment layers. But that also depends on the yeast’s flocularity (amount expended hulls stick together), as gross lees contains a fair amount of yeast hulls as well.

Conventional Wisdom

I was originally taught the 1-3-3 Rule, which means 1 week for fermentation, 3 weeks to next racking, and 3 months to clear. A fair number of the guys that taught me bottled their wine in 4 months, although one barrel aged all his reds for 2 years.

In the last 20 years, the advice I saw most commonly was to get the wine off the gross lees quickly.

Why?

Because the gross lees decomposes and produces off flavors, including hydrogen sulfide (H2S). H2S is easy to detect, as the “aroma” is described as rotten eggs, swamp gas, and/or dog farts. It literally reeks and is to be avoided.

I’ve read various research papers, including one that claimed that gross lees starts decomposing in less than 1 day and the wine is immediately ruined. Ok, I didn’t quite believe that one, and I don’t blindly accept anything as factual without at least a bit of fact checking.

In the past year or so, a lot of folks on WineMakingTalk are practicing Extended Maceration (EM), which is sealing the fermenter before fermentation completes, and aging the wine with the pomace and gross lees for 2 to 8 weeks. This is even longer than the 1-3-3 Rule, and it includes the pomace along with the gross lees.

There’s a lot of contradictory advice in all this — which is correct?

My Conclusions

Some of the following may contradict my earlier statements, but in thinking this through I noticed a few things that contradict conventional racking guidelines.

When to do the next racking after pressing/first racking is not a clear decision. I’ve read that the fruit products start to decompose quickly, which is a reason for stirring daily during fermentation. One source stated that wine must be racked off the gross lees within a day to avoid spoilage … but experience indicates that is not correct. Just because someone posted a study or wrote a book does not mean it’s correct.

Red grapes? Conventional advice says to rack quickly off the gross lees, sometimes within a few days. OTOH, the guys that taught me typically racked 3 weeks after pressing. In further contrast, folks currently doing EM are letting the wine set on the pomace (and gross lees) for up to 8 weeks with no ill effects. So? It appears the need to immediately eliminate the gross lees is overstated for red wine.

I don’t have an explanation on this point — I’m just pointing out facts that contradict conventional advice.

My habit of racking kits between 1.000 and 1.010, and letting fermentation finish for a week or so in the carboy is fine by this standard. I will continue to rack off the gross lees relatively quickly, but won’t stress over it. I’ll wait until the lees starts to compact before racking, to avoid wasting wine unnecessarily.

I suspect this is also true for dark fruit, especially elderberries.

White grapes and light fruit? Both lack the heavy constitution of red grape, so racking off the gross lees in 4 to 7 days makes sense. No one that I know of is leaving them on gross lees for weeks. The lighter body and flavor make it more likely for the gross lees to negatively affect the wine. I’ll err on the side of caution, as once the wine is ruined, there’s no coming back.