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Q: Conversion rate for fermentation?
Question from Karen: I have a question for you… If you crush wine grapes and the juice has 20% sugar, is the alcohol 5%??? Looking forward to your answer. Thank you.
Reply: Hi, Karen! Thanks for writing!
Here’s a brief reply from our winemaker, Geoff Gorsuch: Depending on all the parameters, yeast, temperature, nutrients, and how the crush and pre-fermentation treatment is handled you should end up around 9-12% alcohol if fermentation is finished.” By finished, he means if you let the wine ferment dry rather than stopping it in order to retain some sweetness.
The most common conversion rate of sugar to alcohol is 50-60% and Geoff allowed for a little more than that. The choice of yeast is one of the biggest factors and late-model, “cleaned up” yeasts are playing a role in the whole “hang-time” discussion regarding the alcohol in the finished wine.
Here’s how Wikipedia explains fermentation. Hope that helps! Cheers!
NVWR® 83 – Madeira
April 14, 2009 by David
Filed under Napa Valley Wine Radio
Podcast: Play in new window | Download
In episode 80, Nancy Hawks Miller, our Director of Education, took a broad look at the world of sweet and fortified wines. The episodes that follow, like this one, break it out by category. Today’s topic is the deliciously odd world of Madeira.
Each of these podcasts regarding sweet wines will be released, on a weekly basis, until the series is complete. Complete text is available at goosecross.com (see: Education)
Just Released: 2006 Napa Valley Merlot
Podcast: Play in new window | Download
Better stop by the tasting room! We’ve just released our 2006 Merlot and it’s sure to put a smile on your face. About 1/2 the grapes were grown on our estate right here at the winery. This mid-valley location allows for plenty of ripeness and full, opulent flavors. The rest of the fruit came from the Carneros, where it’s a bit cooler, so the component is a little leaner and higher in acid, which, besides being delicious, brings elegance to the the total blend and helps it comply with our ever present “food-friendly” requirement. 
Speaking of food, a springtime release makes me hungry for Spring Lamb! Colleen put together a delicious recipe that has springtime written all over it – lots of herbs and even some fresh lavender! So, better fire up the grill for Spring Lamb with Honey-Thyme Root Vegetables and be sure to try it with our hot off the presses, 2006 Merlot!
2006 Merlot Audio Winemaker Notes
More recipes, paired with wine!
Cheers!
Trivia du Jour: Sparkling Wine Feels the Pressure
Did you know that the pressure in a bottle of traditional method sparkling wine is typically between 60 and 90 pounds??? The pressure has been compared to the tire pressure in a double-decker bus!! Open with care…
Or, maybe you’d like to know a little more about the bubbly stuff. Santé!
Open That Bottle Night Strikes Again!
You know who you are. You’re one of those people who’s hording a very special bottle of wine for reasons known only to you. Maybe it has sentimental value. Maybe it cost so much that you’re afraid it has you outclassed Whatever… The point is that this beverage has been placed on a such a lofty pedestal that there’s simply no occasion good enough for it.
Enter my favorite wine columnists, Dorothy Gaiter and John Brecher. They’re here to help you. On February 26, 2000, they established what has become a marvelous tradition, and great excuse to over-indulge, called “Open That Bottle Night”. Marching orders: Don’t be silly! It’s just wine, after all… Have yourself a fabulous meal and pop that baby open!
Now, maybe you’re one of those who likes to save the good stuff for yourself, like Nixon, which calls for an extremely intimate dinner party of one. Brings to mind the sad image of Miles, in Sideways, drinking that Ch. Cheval Blanc out of a paper cup all by himself.
Or, instead, you’re the person who, once he realizes he has permission to indulge, can’t wait to trot that coveted wine out and share it with his nearest and dearest. Imagine the potential Bacchanalia if each of those loved ones brings a special bottle of his own. Whoo-hoo!!!!
In any case, it’s just over a week away, so get busy! Get thee to thy wine storage area, pluck that special bottle down from its celestial perch and have yourself a blast on Feb 28! Cheers!
In the cellar today – Topping Barrels
Topping up barrels is a year-round necessity, if somewhat mind numbing. I suppose it’s a great opportunity to run through the entire play list on your ipod or hear your co-worker’s life story…
The great thing about barrels is that they let the wine evaporate, which causes the evolution we treasure.
The bad thing about barrels is they let the wine evaporate, which imperils it. Depending on the humidity in the cellar, up to 5% of the wine can be lost to evaporation each year – read $$$$ evaporating, literally, in front of your eyes. Kind of the cellar equivalent of cluster thinning. The loss is called the “angel’s share”.
Any head space, at the top of the barrel, exposes the wine to bacteria, which can make it smell and taste like “Martha’s Sox” instead of “Martha’s Vineyard”. Soooo sad. And quite unneccessary.
What to do? Add more wine. In fact, let a little wine spill over the top to make sure the barrel is absolutely full. In many cases, one barrel is “cannibalized” to top up the rest. The left-over wine goes into a demi-john for next time (topped up with inert gas).
How often? A good, but controversial, question. Geoff Gorsuch, our Winemaker, tops up each of our approximately 220 barrels at least once a month, depending on the time of year and the barrel. For instance, new barrels can be very thirsty, so they may require more frequent topping at first.
It’s a thankless job, kind of like unloading the dishwasher, but there you have it. Stay tuned for the next spell-binding cellar activity! Cheers!
NVWR® 72 – Do Old Vines Make Better Wine?
October 7, 2008 by David
Filed under Napa Valley Wine Radio
Podcast: Play in new window | Download
Do old vines make better wine? When you see “old vine” on the label, do you assume that the quality will be higher or the flavor more intense? I thought it would be interesting to explore the subject with Winemakers Geoff Gorsuch, Bob Pepi, and Jeff Booth. Enjoy!
Winemakers: Jeff Booth, Geoff Gorsuch, Bob Pepi
NVWR® 66 – Winery Ownership Transitions, Part 1 of 2
June 3, 2008 by David
Filed under Napa Valley Wine Radio
Podcast: Play in new window | Download
A recent study forecast that 50% of family-owned wineries on the west coast will change hands by 2017.
The findings of the survey and report were released by Rob McMillan, of Silicon Valley Bank, and Deborah Steinthal, of Scion Advisors. Goosecross proprietor, David Topper, and Nancy Hawks Miller, Director of Education, talk with Rob and Deborah about what they’ve learned and the implications for the industry. This is the first segment of a two-part interview.
Note: We know that these are two unusually long episodes but we think they will prove to be worth every minute to those truly interested in what makes the wine business tick.
Can California Wines Be Aged?
Question from Jessica: I recently was told by a French wine connoisseur that he would not open a California wine bottle for 10 years +/- as he does with most of his French wines. When I purchased the wine, they told me that California wines are to be opened young. Can you please tell me how to know when to open a wine, specifically a California wine? Thank you.
Reply: Hi, Jessica! Thanks for writing! This seems to be our French vs. California month (see previous post)!
I wish there was a simple answer to your question, but there isn’t. I’ll start by giving you the big picture. I’m going to assume we’re speaking mainly about red wines although there are whites that age well, too.
First, the vast majority of wines are meant for early consumption no matter where they come from. For long-term aging, we’re talking about fine wine.
Second, there can be a difference in longevity between the great wines of California and Europe because of climatic differences. In most of the famous European wine-producing regions the climate errs on the cold side. Cool-climate wines tend to be higher in acid than warm-climate wines and acid is an excellent natural preservative (another natural preservative common to red wine is tannin, which comes from the grape skins). High-acid wines can be hard to drink when they’re young, but they stay lively in the bottle longer.
Most of California leans toward the warm end of the scale, so the wines are often lower in acidity. This usually makes them easy to drink when they’re young, but they may show signs of old age sooner than their cool-climate counterparts.
That’s the big picture, but exceptions abound. If you’ve heard of the “Judgement of Paris” (they’re making two movies about it!), you might be interested to know that a 30th anniversary rematch was held in 2006 pitting approximately 30-year-old wines from California (Bordeaux-types) against great French Bordeaux wines of the same age. The California wines took the top-five ranks.
Longevity can also depend on the grape variety that makes the wine and the specific region and its climate/terrain within the country or state. The variety is stated on the label for most California wines, where French wine is usually named for the region and the varieties used for commercial winemaking in the region are regulated by local authorities. For instance, Beaujolais wines, made of the Gamay grape, aren’t generally intended for long-term aging the way a fine Bordeaux (Cabernet/Merlot) or Burgundy (Pinot Noir) are. Granted, Beaujolais isn’t considered to be in the same league with fine Burgundy or Bordeaux. That’s another reason not to make general assumptions about countries and their wines. A country such as France makes some of the very finest wines in the world and also very ordinary, every-day wines and everything in between – just like California!
So, I’m not trying to dodge your question – I’m trying to suggest that it depends upon the individual wine. Given the big picture, that wine shop didn’t give you such bad advice. Better too young than too old! Please don’t feel shy about asking questions when you buy wine because a good wine shop will have a knowledgeable staff who will be happy to help you.
There’s more detail about aging in this article on our website. I hope this helps! Cheers! Nancy
Cabernet Sauvignon
June 20, 2007 by David
Filed under Winemaker Notes
We all know that Cabernet Sauvignon is the undisputed King of grapes. A serious collector’s cellar will always include great Cabernets, whether they’re from the Medoc, Napa Valley or Coonawara. And it’s probably because it is capable of making a wine of tremendous power, structure and complexity, but it somehow manages to carry this off in a very elegant way. What a wine! You’ll find plenty of examples of 100% Cabernet, but more often it’s blended.
Nancy Hawks Miller, our Director of Education, continues her podcast series of the major wine varietals with Boudreaux’s–and Napa Valley’s–signature red grape.
