Harvest: Red Wine Fermentation: Extracting Colour

There is so much more work involved in the first stages of the life of a red wine, compared to that of a white wine. For the whites, we get the grapes in, and (usually) press them immediately, separating the juice from the skins and sending them off to get started on their fermentation. Easy-peasy. For reds, we're de-stemming, possibly crushing, and then fermenting with all of the skins present. We need the skins because that's where all the colour and tannins reside that are so important for the structure of red wine. The colour and tannins don't just flow freely out of the skins and into our fermenting wine. They need a little coaxing, and two methods we use for that are punchdowns and pumpovers.

Punchdowns are done on open fermenters whether they be stainless steel open-top tanks (which use some kind of temporary cover that is easily removed, or in smaller 1 1/2-ton square wooden fermenters, both of which are used at Babcock. We start punchdowns once the fermentation gets going and the C02 produced starts to force the grapes/skins  to rise to the top of the vessel to form a solid crust or cap. There's not much interaction going on between the fermenting juice and the skins at that point, so we need to immerse that cap into the juice and slosh it around a bit. The process also gets a bit of oxygen into the fermenting juice that the thick cap may be keeping out.

Wineries may punch down from 1-3 times per day throughout the fermentation, decreasing the number of times, perhaps, as the wine gets closer to dry. The punchdowns are evenly spaced throughout the day, so, unfortunately for cellar workers, if there's a third one, it will probably take place in the middle of the night. At Babcock we punch down once per day, but we have a LOT of fermenters to get through.

Because the majority of our reds (Pinot Noirs) are whole-berry, the punchdowns are quite a bit more difficult than they are when the fruit is crushed first. It can be a real challenge to get the punch (a long stainless steel pipe with a flat or curved plate on the end) to make that first break through the cap. Then you gradually move along, breaking through a little bit more at a time until the whole cap has been plunged into the liquid below and loosened up. Here's what it looks like in the 1 1/2-ton fermenter:

If the small fermenter is hard to punch down, the open-top tank, with whole-berry fermentation, is impossible--at least it is for me. Though I haven't seen it myself, they say that the cap will actually support your weight if you were to stand on it. That cap is thick and the surface area is much larger, so it's a real workout for anybody to break on through. Here's Colin working up a sweat:

Pumpovers are used in closed fermenters where you can't get at the surface to punch it down, or in very large tanks. The goal is the same--to wet the cap and get the fermenting wine co-mingling with the skins to draw out the colour and tannins. You get some aeration with this method too (even more than with a punchdown). The idea is to draw the fermenting liquid from the valve at the bottom of the tank and then pump it through a hose up and through the top opening of the tank and over the top of the cap. The liquid then makes its way through the cap, picking up the colour and tannin along the way. At Babcock, someone sits up at the top of the tank directing the flow from the hose so that it hits every part of the cap relatively equally. For a large tank, like the one below, we'll pump over once a day for 30 minutes. We use a pumpover cart that is equipped with a screen in case any grapes/skins come out through the valve--the pump really doesn't like pumping skins!

As you can see, no grapes/skins are caught in the screen here, though. This is because our big tanks are equipped with removable  screens that go on the inside of the tank around the valves. We put them in place before filling the tank, and hey, no pesky skins pouring out of the valve and making more work for us.

This is not the case at Painted Rock, unfortunately. Although the tanks are much smaller, they are not fitted with screens, so the first couple of times we pump over a tank, we are going to have many, many grapes/skins pouring out through the valve and being caught in the cart's screen. It only happens the first couple of times, because early in the fermentation, the grapes/skins have not yet formed the cap at the top and are still floating around down below, near the valve. Once the fermentation really gets going, the bottom of the cap will be well above the valve, so we'll get mostly nice clean liquid. Those first few pumpovers, though, are kinda crazy. When the grapes start pouring out, somebody shovels like mad into buckets, and then the rest of us bucket brigade it up the ladder and into the top of the tank. I have no pics of this because when it happens, it's all hands on deck and no time for taking pictures!

We pump over everything at Painted Rock, and we do it twice a day. At 20 or 25 minutes per tank, when we're at the height of harvest, we may be doing pumpovers for 4 and a half hours straight, and then, a couple of hours later, starting all over again for another 4 and a half hours.

We do have one neat item at Painted Rock that makes pumpovers  more effective. Rather than having someone sit at the top of the tank and point the hose here and there to wet the cap, we have a pumpover irrigator that does the work for us and allows us to do other things while the pumpover is going on. (Well, we still need one person on the ground to monitor the cart and make sure it neither overflows nor runs dry).  Here's what the irrigator looks like:

This isn't a very good picture, so here's a pic from a catalogue of a similar item:

The whole piece clips over the lip of the opening at the top of the tank using the screw-clamp seen halfway down the vertical part. The hose carrying the wine attaches at the top left. The bottom horizontal arm rotates naturally with the flow of the wine. The wine comes out either end and hits the plates below, fanning the liquid out to cover the cap evenly. If you have a larger tank, you can increase the reach of the arm by speeding up the pump and delivering the wine with more force. You can speed up or slow down the rotation of the arm by adjusting the angle of the plates on the bottom. Here's how it looks from the top of the tank:

It's a great piece of equipment but it's kind of heavy and awkward to wrestle in and out of the tanks, and tends to smack you in the shins when you're trying to go up and down ladders with it. Imagine how many bruises you'd get doing that every 20 or 25 minutes for 10 hours a day!

Here's another type of irrigator (called the Toad), that I've seen but have never got to use. It's about 18 inches across and really lightweight. Ahh, that would be so nice!

To summarize, getting the colour and tannin into red wine is hard work! So think of that next time you're admiring the beautiful ruby hues and commenting on the fantastic aging potential and bold structure.

Starting the Fermentation

Once the red grapes are processed, whether they're crushed or just destemmed, they are left to sit for a period of time and then it's time to innoculate with yeast and get the fermentation started. Pre-fermentation cold soaking is popular these days and this year, Babcock is giving it a try on their single vineyard Pinots. We take the newly-filled wooden fermenters, cover them, and store them away in the "cold room" at 48 degrees for 48 hours. At Painted Rock, Bordeaux varieties go through a 3-day cold soak in chilled tanks before starting the fermentation.

The process for adding the yeast involves first getting the yeast active--just as you do when making bread--and then acclimating it to the colder temperature of the grape must in the tanks, before adding it in. For both large tanks and groups of smaller fermenters, we use a cart to do the mixing:

We put in 105-degree F water in an amount appropriate for the size of the tank and the amount of yeast we're using. Then we sprinkle the yeast into the water:

 

And give it a stir:

 

We let it sit for several minutes until it gets frothy and starts working:

Now it's time to start bringing the temperature down gradually. If we were to just dump the yeast in at this point, it would be shocked and wouldn't work. We add some cold juice from the fermenters or, in this case, tank:

We let that sit for a few minutes so the yeast can get used to the new temp:

Then we repeat the process several times, adding a little juice at a time and letting it sit for a few minutes each time:

 The goal is to get the yeast mixture to within 10 degrees F of the temperature in the tank or fermenters. Once we reach that temp, we'll pump the yeast mixture into the tank (or bucket it into the smaller fermenters), and wait for it to work it's magic, usually within a day or so.

 

 

Processing Red Grapes: More Options

Last time, I showed  you the basic destemmer used at Babcock for whole berry fermentation. Today, a couple of other options. At Painted Rock Winery in British Columbia's Okanagan Valley, as well as destemming, we also crush and sort the grapes. In the pic below, you can see the familiar destemmer on the left, the sorting table,(positioned below the destemmer), which feeds into the crusher,(on the right of the pic) which, in turn feeds into the must pump below it. A 4-inch hose is attached at the output end of the must pump in the foreground at the bottom of the pic:

Here's a closeup of the sorting table:

The destemmed grapes fall out of the destemmer and onto the far end of the table. The table jiggles, encouraging the grapes to work their way down the table, and spread themselves out so we can get a good look at them. The main thing we're looking for is jacks (bits of stem) that have found their way through the holes in the destemmer, and any leaves or rotten grapes. The amount of jacks varies according to the grape variety. Varietals with larger berries have fewer jacks slipping through because the grapes are blocking more of the hole. In larger wineries that can absorb the extra cost, they may have several cylinders with different-sized holes corresponding to different grape varieties.

Any juice runs through the slots in the table into the pan below, and from there drains into a bucket. The grapes proceed down to the open end of the table where they empty into the crusher. Here we are hard at work (in this case, sorting Chardonnay):

Spending several hours at a sorting table during a Canadian harvest is not the most enjoyable part of winemaking. Those grapes are cold! With a smaller destemmer, we have to go pretty slow (or it gets clogged up) so it takes about 15 minutes to get through a half-ton bin of grapes. After about 5 minutes, your fingers start to get painfully cold, by 10 minutes, they're numb and don't really work anymore. We keep a bucket of hot water next to us, ready to plunge our hands into the second that bin is finished. The other issue is the jiggling! Some people have a hard time looking at it, and literally get dizzy/nauseous from it. An activity best not done with a hangover!

So why does Painted Rock sort grapes while Babcock doesn't? One reason might be the flavours that may be imparted by the stems. As well as adding tannins, stems might add a green (literally "stemmy") flavour which might not be noticeable with the superripe grapes of California, but might be in BC where the growing season is shorter and the grapes--and subsequent wine--may have more of a green/bell pepper character already. Picking out the jacks may help to mitigate this.

I've also worked at a winery in BC where they sort BEFORE destemming. The whole clusters are dumped onto the sorting table and we pick out leaves and whole bunches of rotten grapes. In retrospect, that's kinda weird, since that level of sorting really should have been done in the vineyard by the pickers.

Anyway, back to Painted Rock: The grapes leave the sorting table and go into the crusher:

There are two sets of interlocking rollers that spin in opposite directions. You can adjust the distance between the rollers to crush the grapes more or less, or to account for larger- or smaller-berried varietals. The crushed grapes fall out the bottom of the crusher and into the must pump:

The auger pushes the must (grapes and juice) through to the hose that's attached at the end (on the right, out of the picture, here), and on into the tank, which is the fermenting vessel of choice at Painted Rock. PR also has a little different system for getting the grapes into the destemmer:

The grapes are dumped into the hopper at the bottom of the elevator, which then takes them up the conveyor and into the small funnel/hopper of the destemmer. We can control the amount of grapes going up the elevator by holding them in the hopper with a pitchfork. That way, the little destemmer doesn't get clogged.

Here's the whole setup:

And from the other side:

Finally, again from Babcock, a relic from the past, the combo crusher/destemmer. Backwards to the way things are done these days, here the grapes are first crushed, and then destemmed:

The above pic is the machine, opened up and partially taken apart. You can see half of the perforated, cylindrical drum in the background. In the machine, itself, you can see the spinning paddles and above that, you can see the 3 parts of the crusher sticking up. A funnel-shaped hopper fits over this top part, guiding the dumped grapes through the crusher, which looks like this up close:

The rollers spin in opposite directions towards each other to crush, in this case, whole clusters of grapes before sending them on to the destemmer.

Just a few examples of how red wines get their start, once they leave the vineyard. Next post, we'll be getting the fermentation started and making these grapes w(h)ine!

First Grapes of 2014!

So excited! We got things started with one of our single vineyard Pinot Noirs that is often the first to come in when harvest gets underway. This one comes from the Rita's Crown vineyard on Santa Rosa Road in the Santa Rita Hills AVA. Our little slice of heaven from that vineyard is called just that--once it gets into bottle--Slice of Heaven.

All of our single vineyard Pinots at Babcock are whole-berry-fermented. This is not to be confused with a whole-cluster fermentation, where the whole bunches, stems and all, go into the fermenting vessel. For whole-berry, we destem, but do not crush. When you destem the grapes, of course a little juice is going to come out because you've broken the skin, but not as much as when you crush. And again, here, don't confuse crushing with pressing. Pressing is what we do after the fermentation is finished (in the case of reds) where we give it a really hard press and get every last bit of liquid out. Crushing is much more gentle, usually done by putting the grapes between spinning rollers that can be adjusted according to grape size and the amount of crushing desired. You end up with a lovely soup of juice and skins, ready for the next step. Whole berry is a little less soupy, but just as lovely.

The trusty old destemmer at Babcock has some nifty modifications. There is a standard type of destemmer that is widely used, and necessitates placing a vessel under the destemmer to catch the grapes and then pallet-jacking that vessel out from underneath--kind of slow and laborious. But here's what happens at our place:

We have 2 sets of tracks with rollers that use gravity to push a series of bins (white bins on the left catch the discarded stems, and white plastic-lined brown, wooden fermenting bins on the right catch the grapes) under the destemmer. The comparatively small portion of this contraption--the part with the faded blue on the left end, the red and black graphic to the right of that, the small, funnelly part on the right end and the thin blue plastic strip below that, is what constitutes the actual destemmer. The rest is all for loading and unloading of the machine. In this pic, the forklift has just loaded the first of the wooden bins (for grapes) at the far end, and it's rolling down into position next to the white bin (for stems). When the bins are loaded and we're ready to go, from the side, it looks like this:

You can see there's quite a steep grade the bins are coming down, and that the first fermenter bin on the left is now in position under the small plastic blue chute where the grapes are going to come out. How does it stay in position and not roll forward too far? That's the cool part. there's a horizontal bar (just even with the upright post of the frame at the back of the leftmost bin), operated by a switch, that comes down and traps the bin right where you want it. In the pic below, you can see the bar holding the plastic-lined bin (the other thin metal sheet clips over the tops of 2 bins to keep them from separating). When that bin is full, we raise the horizontal bar and gravity forces the bin down to the end where a forklift is waiting to whisk it away to its next adventure. As the bins fill, we take them away at one end, the empty ones roll down into place, and we load more empty ones at the other end. Same goes for the other track with the white bins for stems.

 

So the grapes start out by getting dumped into the large hopper on top that funnels them down to its bottom: 

 

At the bottom of that is an auger-thing that herds them through a short tunnel and then down into the small funnelly hopper at the right end of the destemmer-proper:

Grapes get spit out pretty quickly (through the blue chute) and stems continue on to their fate at the other end of the destemmer, ending up in the white bins.

The forklifts have cool attachments for dumping the bins. They grab on to the sides and the front of the 1/2 ton picking bins, as well as having forks through the bottom, so you can turn them almost completely upside down without dropping them. In other wineries, I've also seen forklifts that dump sideways instead of frontwards as we do here:

After dumping the bin, we rinse it with hot water immediately to keep the grape material from hardening on in the hot sun.

But just how does the destemmer work? Well, inside that comparatively small metal box, there is a horizontally spinning cylinder full of holes, through which the grapes fall into the chute and into the fermenter. The following are pics of the destemmer at Painted Rock Winery in British Columbia (same type as Babcock uses, just a little smaller). All that pink is from tartrates, built up over many days of destemming during harvest 2013.

The stems are too gangly to easily fall through these holes. Within the cylinder, is a spinning thing with paddles:

It drives the stems to the other end of the destemmer where they are spat out and discarded (or used to fertilize the vineyard).

So it all kinda goes together like this, within the main rectangular box that is the destemmer. First is the empty destemmer housing with the side panels open and seen from the end opposite the small hopper (you can see the chute where the grapes go down:

Same view with the cylinder in place:

Same view with the paddles in place:

Altogether, but with side panels open:

All put together and with side panels closed:

Next time, I'll talk about some other setups for processing red grapes.

Harvest, here we come!

Well, that was certainly a longer break from the blog than anticipated, but here I am, back again, 4 years later! Since I last wrote, I've done 3 harvests in British Columbia, but I'm now back in California, and back at Babcock Winery, on the eve of the first day of this year's harvest. Harvest is so crazy, there's really no time to be writing a blog, but this year I'm in a bit of a unique situation. I'm taking a couple of winemaking courses this fall, so I'll have a couple days off per week from the harvest madness. I'm hoping to have time to post here as well as get my schoolwork done. The rest of today's post will be pictorial, showing you the progress of some Pinot Noir grapes at Babcock since budbreak in spring.

Budbreak, early March :

At 4 weeks after budbreak:

At 7 weeks:

At 8 weeks, flowering!:

Vine growth at 8 weeks:

At 12 weeks, berries forming:

At 14 weeks:

At 16 weeks:

Vine growth at 16 weeks:

At 17 weeks:

At 18 weeks, Veraison!

At 20 weeks:

Vine growth at 20 weeks:

at 21 weeks:

At 22 weeks:

At 23 weeks, almost ready to go!