Pressure, Pressure.. oh, the relief!

Spring has sprung in eastern Massachusetts over the past few weeks. The birds are singing and gettin' busy--last week I backed out of the garage in the morning to find two pairs of wild turkeys in my yard with the males in full courtship display. The snow is gone, and it's been shorts weather a couple of days. What I've found interesting is how the weather has affected my cranberry-niagra grape wine. A couple of posts ago, I mentioned how stubborn this wine has been in clearing. In contrast to the cranberry-banana that was started and fermented at the same time, the cran-niagra has very, very, very slowly clearing. A couple of weeks after the first racking in February, there was a definite strata in the wine with the bottom 2/3 cloudy while the top 1/3 began to clear. And this strata stayed there through the month of March and first week of April. But rather interestingly, the high pressure system that moved into New England and stayed over the past 2 weeks with 60-70° temperatures suddenly caused the wine to drop all of its sediment. The carboy is clear from top to bottom with a good layer of lees on the bottom. It's still not as translucent as the cranberry-banana, but I would call it clear.

I believe this atmospheric pressure-initiated clearing may be a result of degassing as the wine has risen in temperature about 10 °F. My basement has gone from about 45 °F this winter to about 55 °F this month. Cold wine dissolves more residual CO2 from the fermentation. The warmer temperatures brought by the high pressure system may have let the wine warm up to get enough CO2 to degas and let the small protein particles fall out of the suspension. The warmer temperatures have also caused the wine to expand as it warms, as I've had to suck a little out of each carboy to keep it from expanding into the airlock.

Not only is wine all about the chemistry, but it's also all about the physics! If only I had been told that in high school physics!

Salute,
a Wine Student

A Blending Experiment

Had some free time on Sunday afternoon, so I decided to get drunk. Oops, I mean I decided to take a stab at blending some of my 2006 red wines!

I've been thinking about this for some time because I'm just not all that happy with the zinfandel that I made from grapes shipped from the Central Valley in California. I bought them from a winemaking store in southeast Michigan that was sourcing grapes for the first time. I don't think they had a very good grape source because the grapes just didn't taste all that good when I picked them up. Hard to explain, but they just weren't very flavorful and had a rather chalky aftertaste. That lack of flavor and chalky taste persisted through the fermentation and aging. I also didn't get a lot of color and tannin extraction, so I ended up with a pretty light colored and bland, chalky wine. I may be overstated things, but the wine is not something I look forward to drinking or giving away, which is not good because I've got 4 cases of the stuff!

I've also been tasting some of the red wines that I made from grapes purchased in the Finger Lakes of New York and have been much more impressed with the flavors, colors, and tannin profiles. After some mulling, I decided to see what I could achieve by blending the CA zinfandel with some NY cabernet franc and noiret wines. Of course, blending requires multiple bench tests of different blend ratios to determine the optimal ratios, so I was in for an afternoon of drinking! I will admit that I had to take a break for a couple of hours to sober up and continue. I have not mastered the art of sipping and spitting!

I started with blending the zinfandel with noiret because the noiret came out with strong cherry and pepper flavors/aromas, heavy tannins, and just black as night, and I thought it would add a lot that the zin was missing. I was very pleased to see that I was correct. Adding the noiret really perked up the zin! I started with a 90/10 zinfanel/noiret ratio and worked my way up to a 50/50 blend. After tasting through the panel several times, both my wife and I agreed that we liked the 50/50 and 60/40 zin/noiret blends the best.

I was pleased with the zin/noiret blend, but wanted to try a tertiary blend by adding some NY cabernet franc as it has a lot of the same cherry & pepper flavors as the noiret, but also some interesting creamy vanilla notes that I thought might help round the aroma and taste. I didn't do a complete investigation because I was getting a little loopy by now and simply couldn't last through a 3-dimensional blending test. I decided to take the 60/40 zin/noiret blend and see what would happen if I added a little cab franc in increments for 60/40/10 to 60/40/50. Interestingly, the vanilla came through even at the 60/40/10 ratio, but was soon overpowered by some emerging tartness. In the end, I felt that a 60/40/25 zin/noiret/cab franc blend was the absolute best of the evening. And guess what--my wife agreed!

My plan for the coming weekend is to pop open some bottles and make 3 gal of this 60/40/25 zinfandel/noiret/cabernet franc blend. Going to have to brush up on my fraction math so I get the right amount of the different varietals into the carboy! It will be interesting to see how the wine chemistry works after blending. I'm anticipating that I might see some additional sedimentation after everything is mixed and the wine pH stabilizes. I may even decided to do some additional oaking on the blend--we'll see.

It took quite a bit of additional wine to make this zinfandel more palatable, since I'm diluting it at almost a 1:1 ratio with the other wines. However, I'm pretty pleased with the result. I'm going to give it about a month or two to meld together before rebottling and reporting on the results. Stay tuned!

Salute,
a Wine Student

p.s. Someone once told me that all blends were crap wine. In some respects, I am trying to pass a substandard wine off as something drinkable. On the other hand, I'm doing what I need to do to produce a wine that I'll drink!

p.s. #2 Just to be clear, I strongly disagree with the notion that only single varietal wines are "good". Look at the Bourdeaux blends! Winemakers have been blending wines for years to make an improved product.

Silcone--Better Wine through Chemistry!

I've been intrigued with breathable silicone bungs for quite some time. They (upper picture) are supposed to allow dissolved CO2 and other gases slowly escape from the wine, while not allowing air (and dreaded O2) back in. Now, the water-filled airlocks (lower picture) do the same thing, although if there is a change in the barometric pressure when a storm comes through or winter slowly turns to spring, the wine can shrink in volume and suck water back into the wine risking bacterial contamination. Plus, you do have to keep an eye on the water level in the airlock to make sure that it doesn't evaporate below the entrance and let O2 into the carboy.

I've heard good things from folks who have used the breathable silicone bungs, so I've been wanting to purchase some. Only problem has been that every time I got serious about placing an order, Valley Vintner was out of stock and back-ordered. My luck changed a few weeks ago and they were in stock when I needed to purchase supplies for the upcoming Chilian grape season. So I bought some!

I decided to give one a try last weekend when I racked the 2008 blueberry off the lees layer. Instead of an airlock, I rammed in a fancy new breathable silicon bung into the carboy. So far, so good. A warm front came through last night and the the pressure differential in the carboy and the atmosphere pushed the bung slightly out. Not enough to break the seal fortunately, so I pushed it back in and adjusted the moveable flap to allow less pressure to move it.

This is something that's going to take a long time to evaluate whether I want to completely switch from the airlocks to the breathable silicon bung. In the meantime, I certainly do enjoy some new toys and feel like I'm living up to my chemistry background by utilizing products that could only be produced by a chemist. OK, I suppose a chemical engineer could come up with this as well, but it would have been a stretch!

Apologies to all you chemical engineers that just so happen to read this blog....

Salute,
a Wine Student.

p.s. You know, the pictures looked just fine on the camera, but man are they dark! I'll have to take new brighter pictures and replace these.

Blueberry 2008 in the carboy

Well, the blueberry fermentation is finally complete. Seems like it took forever to ferment to dryness (it has actually been 34 days). I'm actually not entirely sure if it had completely stopped fermenting. I could see a very slow, but steady evolution of tiny bubbles that led to a bubble in the airlock about every 2-3 minutes. However, the brix level had remained steady over 3 days at Brix = -1.5. I double check with a hydrometer and found that the SG = 0.995, which is considered dry. So I decided to rack last Thursday (3/18/08) and treat with an extra heavy dose of sulfites. Given how long the fermentation took, I'm wondering if I should increase my yeast nutrient dose? I've never had fermentations last this long...

After racking, I filled a 3 gal carboy and a 1.5L bottle (picture to the right). What a lovely, deep, deep, dark purple color! The taste is actually pretty good, as well. Still rather sharp from the dissolved CO2, but some nice dark fruit flavors and good mouthfeel. I think I'm going to need to add some more tartaric acid after it clears, but we'll wait and see.

Let the clearing begin!

Salute,
A Wine Student

Blueberry 2008 prior posts:
Initial Mix
Yeast Addition and Oxi-Clean
Pressing Blues

Cranberry Clearing

It's been a little over a month since I last racked the cranberry wines off the gross lees. On Saturday, I went down to the wine cellar for another reason, but was struck by the different rates at which my Cranberry-Niagra and Cranberry-Banana wines are clearing. During the last racking in February, the Cranberry-Banana had won the prize for the most sediment, so I wasn't overly surprised to see how much clearer it was. However, that wine is almost crystal clear. The picture on the right shows how clear it is (carboy on the right). The Cranberry-Niagra (on the left in the picture) had dropped a lot of sediment in the past month, but still has a long way to go.

I was expecting this difference, as banana wines are known for their fast clearing rates. However I've never seen this in person until these wines.

Salute,
a Wine Student

Prior Cranberry 2008 posts:
Starting the Body Experiment
Fermentation Almost Done
Racked the Cranberry-Grape
Racked the Cranberry-Banana
Racking off the Gross Lees

Introducing the Macchine Enologiche!

I recently received a bonus at work, so I decided to spend it on myself and bought a new crusher/destemmer (I'm doing my economy stimulus part)! I'm proud to introduce my latest baby--the Macchine Enologiche! This recent arrival to these shores sports 100% Italian craftsmanship, stainless steel hopper and working parts, and an electric motor to make short shift of those pesky grapes. No grape can stand up to its awesome crushing power--bwahahaha!

Sorry, I think I was channeling Tim "The Tool Man" Taylor there for a moment!

During the 2006 grape season, I used an antique crusher for my cabernet sauvignon and zinfandel grapes. I had bought it from the same folks that sold me a grape press. They used to run a winemaking store in Colorado and both the crusher and press were the store's equipment. Lots of good karma there. Unfortunately, the crusher did not have a destemmer, so I literally spent 4 hours bent over a bin full of 100 lbs of grape must, hand sifting out as many stems as I could. My back simply can't take that again. During the trip to New York to pick up some grapes, I made use of the vineyard's crusher/destemmer. These lovely devices crush the grapes and then sift out the stems before dropping the grape mush into your collection bin. What took me 4 hrs of back-numbing work before was done in 15 minutes, and the only sweat I worked up was in moving the collection bins into the back of my truck. Ever since then, I've been lusting after one of these beauties. With the upcoming Chilean season, and my recent bonus, I took the plunge! Now that it is in my basement, my first thought was "Wow, that's big!" Oh well, it will certainly make my life easier this spring and fall, and many subsequent years. It will keep my wife from getting bored while we hand destemmed. And it is large enough for a small winery, so let's call it an investment in the possible future!

Say hello to my new baby--the gleaming Macchine Enologiche! She needs a better name--something feminine in Italian. Perhaps Vinia (Latin for wine)? Other suggestions?

Salute,
a Wine Student

Blueberry 2008--A Pressing Issue

The past few weeks have been very busy--computer troubles, a sick guinea pig (now there's an interesting story), and the usual work load, so I've been thankful that the blueberry wine that I started on Feb 12 has been quietly bubbling away in the kitchen corner. However, all good fermentations must come to an end, and indeed, the yeast activity on this batch began to significantly drop in the past few days. On Thursday night, it had reached Brix = 2.6 so I decided to press and transfer to a carboy.

Now some people use a small press for their fruit wines. Not me, I use a hands-on approach. I line a plastic bucket with a nylon mesh bag, pour the must into the bag/bucket, and then lift up the bag to let the wine drain out. Yes, it's a little labor and time intensive, but it's cheap (no wonder I fit into New England well), and easy to clean up. Plus, I get to get my hands dirty!

Disclaimer--I am not and never was a member of any "Athletic Department". Although lifting a 4 gal bag of fermenting mush isn't trivial! And I do seem to have the hairy chest to match!

For those who recall the mess I made when I added the yeast (see post), I am sitting on a layer of plastic. Note the stain free wall and cabinets behind me (Thank you, Oxiclean)! Now, don't freak out--there is no fire hazard in this process, that's just where I keep the extinguisher because I haven't yet hung it on the wall. Trust me, I'm not that dangerous in the kitchen!

After pressing, I poured the liquid into a carboy and topped with an airlock to let the fermentation finish. I'm not worried about the airspace in the carboy at this point because the must is still giving off CO2 that will displace the air in the carboy. I've moved the carboy to the warmest place in the house (the guest bathroom) to finish fermentation, and it is dutifully slowly bubbling away. Will probably be done within a week. At that point, I'll rack into a smaller carboy and top off to protect it from oxidation.

I'm quite pleased with the color extraction that I achieved. Adding the Lallzyme EX during the cold soak really gave a boost of color. Of course, a lot of that color will drop out as the wine clears, but we're starting at a very inky reddish-purple, so the final result should still be very dark.

So far, so good!

Salute,
a Wine Student

Blueberry 2008 prior posts:
Initial Mix
Yeast Addition and Oxi-Clean