Harvest begins

from grapes to wine

As the grapes ripen, most eyes are on the vineyard. Watching the color of the grapes and checking the sugar levels. They call the sugar level in the grapes Brix. Brix translate into the final alcohol level in the wine. This is because during fermentation those yeasties are going to break down the sugars and turn that into alcohol, so the science says that if you pick a grape at 26 Brix you will get a wine in the end that is around 14.5. The sugars in the grape are affected by the climate. Warmer climates cause the grapes to get riper, the sugars higher and the resulting wines will be higher in alcohol and vice versa. So the winemaker is looking at all these factors when deciding when to pick the grapes. Of course, in addition to the sugars the rest of the grape has to be ripe. Also the different varieties of grapes ripen differently as do sections of the vineyard depending on where they are on a hill.



Summer in the vineyard is the start of the busy season. The vines are growing and there is lots of farming work to do. As the vines start to climb they need to be trained and often cut back to allow for the proper number of clusters to develop the best potential of flavor in the grapes and here positioning is important also, for easy of picking, reducing rot and even ripening.




With eyes on the vineyards, watching the color of the grapes and checking the sugar levels. Barrels and fermentation tanks are getting cleaned and ready, the bins and other equipment are getting set up and ready. Harvest arrives and things start early. It is best to pick fruit early in the morning before the morning sun warms up the fruit and the sugars start to change. The fruit is also firmer then in the cold morning and stays fresher as you get it to the crush pad.

the harvest

Harvest arrives and things start early. It is best to pick fruit early in the morning before the morning sun warms up the fruit and the sugars start to change. The fruit is also firmer then in the cold morning and stays fresher as you get it to the crush pad.

So the vineyard has a bunch of people dressed in layers, buckets and clippers in hand, who then leap frog down the rows clipping bunches to fill their bucket then getting them into the larger bins on the tractor, where other people stand over pulling out the MOG (material other than grapes).

The bins go back to the winery to the sorting table where any extra leaves and stems are pulled out, as well as unripe or over ripe fruit. Here is where the decision is made for stem inclusion or not. There is a machine called a destemmer/crusher that separates the grapes from the stems and then crushes them. From there…well, then you get into all the great cellar stuff like pressing, fermentation, pump downs, and getting it into barrels. This is the busy season. But out in the field, there is still something happening

Vintage 2014 Grapes










Punch downs

Pump overs





Stainless tanks

Concrete eggs



Neutral or new

American, Hungarian, French

Toasted heads or more



Bottle type

Bordeaux or Burgundy bottle

Glass thickness, punt


Screw cap, cork, composite


Foil or wax


The bins go back to the winery to the sorting table where any extra leaves and stems are pulled out. Here is where the decision is made for stem inclusion or not. There is a machine called a destemmer/crusher that separates the grapes from the stems and then crushes them. Once the grapes skin is broken, the yeasts (these can be the natural ones on the outside of the grape, or in the air, or they can be added yeasts in the winery) get working on fermentation.

White Wine will go to the press after it is crushed to press the juice out and leave behind the skins and seeds. From here it goes into tanks to settle and let any other sediment fall to the bottom, then it is “racked”, filtering out all that extra sediment and leaving clean juice.

If it’s red wine, well…if you want it to be red then you start the fermentation process with those skins which give it its color. Or not, and then you are probably making a light rose.


Tanks of wine at a California winery

So as I mentioned before the grapes can start fermenting as soon as the skins are broken and the yeast has a chance to get into the sugary juice, but typically fermentation won’t happen when it is cold. This is why they harvest at night and keep the initial tanks cold to keep things from fermenting too soon.

At this point the wine goes into vats and the winemaker either adds their yeast of choice (which you can buy in bags much larger than the ones you get to make bread in the store), or they wait for the natural yeasts on the grapes and in the air to start doing their thing. That second one is known as Natural yeast fermentation. Here’s the thing about yeast, it gets around. You would be surprised at all the yeast that is in the air around you and if multiple wineries are near each other (like warehouse wineries) they have to be very careful about cross contamination.

So the yeast gets going eating the sugar and causing fermentation.

In the red wines the CO2 will cause the grape skins to float to the surface, that is when the cellar team does punch downs or pump overs. The “cap” as it is known, either gets punched down with someone standing over the vat and pushing it down with a large tool, or you can pump the juice back up and over to push the cap down and keep the skins in contact with the fermenting juice.

While on the Central Coast in April we were lucky enough to meet with Jason Haas, General Manager of Tablas Creek Vineyard in Paso Robles. Jason graciously took time out of his busy schedule to spend a couple of hours with Michael and I in the vineyard and the winery.

Tablas Creek Vineyard is the collaborative effort between the Perrin Family of Chateau du Beaucastel in Chateauneuf du Pape in France’s Rhone Valley and the Haas Family. Vineyard Brands, the wine import company founded by Robert Haas had been the exclusive importer for Beaucastel wines. In 1989 they founded Tablas Creek Vineyard in the west side of Paso Robles to grow Rhone varieties.

Native Yeast Fermentation

I have always been fascinated by native yeast fermentation. Many winemakers find it to be too risky, so I took this opportunity to ask Jason about the native yeast fermentation at Tablas Creek and how they might handle a “stuck” fermentation. Jason mentioned that often native yeast fermentation is described as “hands off” wine making. He looks at it more as “fingerprints off” wine making because the process actually makes you more “hands on”. During fermentation they are closely monitoring each lot and testing to be sure it is perking away. If a lot is not fermenting well or looks like it is getting stuck, they have options. They can mix the lot with another lot that is fermenting well or pump it over the lees of something that is fermenting well. They can build a culture from a tank that is doing well and release it into a tank that isn’t. So they don’t get “stuck”, they just have to work harder. Using only native yeast is another way of expressing the uniqueness of the site or the “terroir” which is something that Tablas Creek is passionate about.

Use of Foudres

There are few places in California that you will see foudres used. Foudres are 1200 gallon barrels (as opposed to a typical wine barrel that holds 60 gallons). When you walk into the Tablas Creek Vineyards tasting room you can see these beautiful large foudres through the glass windows that surround the tasting room. As Jason explains it, when you are aging a wine you must determine how much oxygen and how much oak you want. As they follow the Chateau du Beaucastel style they are looking for very minor but consistent oxygen and very little oak. As a result, large wood it the way to go. With a 1200 gallon Foudre you have 20 times the wine and just 4 times the surface area compared to a normal 60 gallon barrel. This gives you more volume to surface area. The staves in these larger barrels are thicker also, which makes the penetration of oxygen slower. This is perfect for protecting Grenache which is prone to oxidation and for Syrah and Mourvedre which are prone to reduction which can cause them to go funky. The large foudres give a balance allowing the wines to age gently and still progress..

the aging process

Often white wines won’t see a barrel. You’ve heard of Stainless Steel style Chardonnays. They don’t go into a barrel, but finish their lives in the big Stainless Steel Tanks.

Other white wines and most red wines will be filtered and go into barrels to age for several months or longer (sometimes much longer). The wines age and depending on the age, size and style of the barrel, they will pick up flavor through the oak of the barrels.

And some wines won’t get filtered. You will find white wines that have been aging on the lees. “Lees” that’s the dead yeast, that sank to the bottom. This will often give a wine a richer mouth feel, creamier.

Wines can go into concrete eggs or even square concrete tanks for aging. When you age wine in a vessel with a permeable surface, oxygen can get in (and out). This also allows for evaporation. The term “Angels share” refers to the wine (or alcohol, you hear this term lately on whisky, bourbon and scotch commercials) that evaporates through the wood, causing the wines to need to be periodically “topped off”.

Lastly the winemaker decides how long the wine should age. Some wines will be quick, others, especially heavier reds can be 2 years or more in barrel before bottling.

Wooden Barrels come in many sizes, from the normal barrique which hold 60 gallons to the 1200 gallon Foudres. The surface area exposed to the wood and the oxygen change depending on the size of the barrel and this affects how the wine ages.


Then there is the type of oak. French Oak has the highest tannins, and is a bit more subtle than American oak. Hungarian Oak has a much tighter grain which typically makes it more “neutral” or less likely to impart its oakiness to the wine.

The number of uses a barrel has also affects how “neutral” it is. A new French Oak barrel will impart lots of tannins and oak flavor into a wine. A French Oak barrel that has been used several times, will be more “neutral”.

Toasting barrels is an artisan trade. As the barrel staves are put together they are toasted with fire to burn the insides. Cooperages (those people who make the barrels), specialize in specific toasts for the staves or heads of the barrels, which can be light, medium or heavy.

Wine Barrel's Stacked

Wine Barrel’s Stacked

Now the barrels we are talking about here are the standard 60 gallon barrels that are used in many wineries. The ones you see turned later into planters and lawn furniture. There is a whole different world of barrels out there that are much larger. A great example of these larger wooden barrels can be seen in southern Rhone Style wines where you want less oak contact. Tablas Creek has great (and might I say stunningly beautiful) examples of these.

Barriques are the French term for the typical 60 gallon barrels.

Foudres are 1200 gallon French Oak barrels and hold enough wine to fill 500 twelve-bottle cases.

Puncheons are 120 gallon barrels.

Demi-muids are 160 gallon barrels.

There are also 1600-gallon wooden casks that stand upright, like a fermentation tank.

Wine Barrels Foudre

Foudres, 1200 Galllon French Barrel’s

Other types of containers available

Flextank and other companies create plastic wine tanks that replicate barrel functions and are space efficient. If you do not need oak flavor…well you can reuse these multiple times.
Vino Vessel originated in Paso Robles and is a company that creates concrete fermentation and storage tanks. The benefits are that they are more affordable, easier to clean, less space and labor intensive and longer lasting. They also offer more natural oxygenation than stainless steel does and they are naturally stay cooler so they reduce refrigeration costs.
Stainless Steel has no oxygen exchange and is initially expensive, but can be used repeatedly. They can be fitted with wood staves to impart flavor.

Okay speaking of adding staves…you can use these alternative vessels for aging your wine and still get oak flavor by adding staves and or oak chips.

So that’s the basics of barrels. This is not to be confused with fermentation tanks. That’s a whole ‘nother chapter!

Wine Barrels 101

Wine Urn’sWine barrels stacked in old cellarWine began stored and aged in amphorae (sealed earthenware or clay jars) that were used in Greece and Rome.

It was the Celts in around 50BD that devised using wooden barrels to store and transport wines (those Celts…so smart!)

Wooden barrels were sturdy and shaped conveniently for transport. And…it seemed that wine could actually benefit from the wood!

Why Oak? Some would say out of convenience and then as a taste preference. There are over 400 species of oak. Only about 20 of them are typically used for wine barrels and these can very with the flavors they impart although most often the flavor noticed is “vanilla”.

In addition to the wood itself you have the toast. Cooperages specialize in specific toasts for the staves and heads of the barrels and the intensity of the toast can definitely affect the flavor of the wine. Toasts are labeled as light, medium or heavy and can very from the barrel staves to the head.

Barrels allow the introduction of oxygen to the wine in a very slow manner. The pace of the introduction depends on the tightness of the grain of the wood. It also imparts the wood flavor into the wine as well as tannins, and body. The body comes mostly from the sugars that are formed when the oak is toasted.

When speaking of types of Oak:

French oak has the highest tannins. They tend to be more subtle than American Oak. They are distinguished by which forest they come from with 5 major regions. The trees used are between 120-150 years old and are strictly controlled by the French Department de Eaux et de Forets. The rough staves are typically air dried for 2 to 3 years before the barrels are made. French barrels can run between $800 and $3600 each.
American oak is the opposite extreme with grains that are not nearly as tight. Here you get much bolder flavors including spice, vanilla and butter. American oak primarily comes from the Midwest, Appalachia and Oregon. American oak is much more affordable at $300-$500 per barrel.
Hungarian is usually thought of as the tightest grain, this makes it more neutral, imparting less flavors even when it is new as well as typically being lower in tannins. Hungarian oak sits right between the two cost wise at $500-$700 per barrel.

Barrels lose their flavor as they age. Typical barrels can be used for about 5 years before they are done imparting flavor. You get the most flavor extracted on the first use, about 50%. The second use you get about 25% and after that the barrel dwindles toward what is referred to as neutral oak or a barrel that no longer imparts noticeable oak flavor. So…if after 5 years you have wines to age in neutral oak, you are good! You can keep using those barrels for 100 years or so!

You can increase the life of the barrel and get more use out of it. I have seen photos from the Cilurzo winery in Temecula back in the 60’s shaving down the inside of the barrels to get more exposure to the oak. Shaving at this time was a special art and the people who did it travelled from winery to winery doing this. This practice picked up in the 80’s and 90’s. Barrels would be shaved and then re-toasted. Shaving costs run about $75 per barrel. A new company out of Australia has a new robot called the Phoenix that uses a high-speed cutting tool to cut 9-10 mm from each stave. This is done by first mapping the interior of the barrel with a laser. Once the interior is cut down the barrels are re-toasted with an infrared machine. I have heard also of adding new thinner staves that have been toasted to neutral barrels.


We will get into bottling but keep in mind that many wineries are using other methods. Wine Kegs are great for restaurants and bars and cut down on waste. Box and bag wines have popped up in many places and while they were initially used by bulk wineries and and such not very well thought of, more wineries with higher quality wine are going down this path, finding new packaging methods convenient for customers. So don’t over look those quirky juice box style wines, some of them are filled with primo juice!

For the most part, wine bottles come in 2 basic shapes, Bordeaux bottles are the talk bottles with high shoulders. Burgundy bottles have a lower sloping shoulder. These two styles can come in various colors. Typically red wines come in green glass to protect them from sunlight. They also may have a variety of “punts”, the divot in the bottom of the bottle.

In addition you have sparkling wine bottles which are made of heavier glass, because of the additional pressure caused by the bubble inside.

Dessert style bottles will be smaller and the shape typically gives you an idea of what style of dessert wine it is.

Then there are unique bottles, like those straw wrapped Chianti bottles.

Now the bottling machine goes to work. This automated assembly line often is on a truck that can drive from winery to winery taking care of their bottling needs.

After the bottles are set up, the bottles are sparged with nitrogen to replace oxygen, this prevents unwanted oxygen from getting in the bottles. (Nitrogen is heavier than oxygen so it forces the oxygen out of the bottles)

The bottles are filled with the wine. The filler drops into the top of the bottle and the wine runs down the sides of the bottle.

Now your cork or composite closure is put in the neck of the bottle. In a bottling truck these would be fully automatic.   They are also available in Semi automatic, vacuum cooker style and hand corkers, for smaller productions.

And keep in mind that screw tops for wine have become more common in the marketplace. Larry Schaffer, the winemaker and owner of Tercero Wines is a proponent of this type closure, which cannot leave cork taint!

A tin or foil seal is slipped on the top of the bottle and a then another device seals this capsule on. These may have logos or designs on them. Or perhaps the winery will choose not to use them. Often now the cork will have a logo printed on the end and the bottle will go without a capsule.

Finally the labels are applied to the front and back.

In some cases and with smaller lots, wineries might opt to forego the tin seal and do a wax seal over the top of the bottle. I had an opportunity to learn how to do this on a visit to Riverbench Vineyard.

Finally the wine will be on it’s way to you. Unless it is from a winery that prefers to bottle age their wines before releasing.

The wine will continue to age in the bottle and hopefully in your cellar. Mostly you bottle age reds, but I have several beautiful bottles of Roussanne in my cellar that will just keep getting better.

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