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Frontenac Gris Rosé

April 19, 2012 by

I realize I am WAY behind in updating this blog. I will try to remedy this in the coming weeks.

I have a lot to write about, as we recently finished our tasting evaluations of our 2011 wines. Although the majority of the wines we evaluated are Minnesota selections that haven’t been released, we were also able to do some evaluations of our trials with Minnesota cultivars. Today I’ll talk about one of our trials: Frontenac gris rosé.

There are two methods one can employ to make a rosé wine. The first, which I mentioned in my Marquette vinification trial post last year, is the saignee method or “tank bleeding.” Essentially you fill your tank with red grapes, and do a cold soak for anywhere between 6 and 24 hours. This allows time for some of the color from the skin of the grapes to seep into the colorless juice. The longer you let them soak, the darker the color. After the desired soaking time has passed, you open the racking valve at the bottom of your tank (with a hose attached, of course), and pump 5-10% of the volume of your tank into another tank. Then, you ferment your red grapes to make a red wine, and your saignee juice is fermented as a rosé. Of course, this method is typically employed with Vitis vinifera grapes, of which most have colorless  pulp. Most of our hybrid grapes have colored pulp and skin, so this maceration step is unnecessary if you wish to make a rosé from Frontenac or Marquette. Often the problem with Frontenac rosé especially is that its color is more of a claret rather than a rosé – even without any skin contact!

So that brings me to the second method of making a rosé. The French would argue that this is the only way to make a rosé (unless you’re in Champagne). It’s the direct press method. This how I would recommend rosé made from Frontenac or Marquette should be done. With the saignee method, it may be difficult to achieve a lighter-colored wine. With the direct-press method you essentially treat the red grapes as if they were white grapes.  You press the grapes right after harvest and can crush/de-stem, or press them whole-cluster. If you whole-cluster press you may be able to achieve a lighter color because of adsorption of anthocyanins to the stems.  Of course if you were using Vitis vinifera like they do in Provence, you would need a short maceration time to achieve some color extraction. Traditionally, the grapes would be crushed, de-stemmed, and macerated for a short period of time. Maceration often takes place directly in press.

Although I mentioned Frontenac and Marquette as two red grapes that can be used to make a rosé, there is a third option: Frontenac Gris. Frontenac Gris does not contain anthocyanins (red pigments) in the pulp like Frontenac. However, it still retains some red color in the skin. If you press the grapes immediately after harvest, it yields a gold to amber-colored juice. But, if you allow a certain amount of skin contact (or if you over-extract during pressing), you can extract some of the color from the skins. Thus, it is really the only grape we have that can be handled as one would handle V. vinifera when making a rosé.

Knowing that Frontenac Gris isn’t as highly colored as a red grape, our skin contact time needed to be longer than the 6-24 hours traditionally needed for making a rosé from red (vinifera) grapes. We decided to do two trials: a 3-day pre-fermentation maceration, and a second where we actually fermented the grapes on the skins. We already knew that fermenting Frontenac Gris on the skins (when we made a FG port last year) gave us a really pretty dark pink wine, so I wasn’t too worried about too much color. The idea was to see what we could achieve with maximum anthocyanin extraction during alcoholic fermentation. It’s important to remember that a certain percentage of color will be lost immediately after fermentation. Another percentage is lost with sulfur addition. So, if the color of your wine doesn’t resemble the color of your juice, then this is why.

So here’s a picture of the color difference between our two trials. See if you can pick out which was a 3-day cold soak prior to fermentation and which was fermented on the skins:

If you couldn’t figure it out, the wine on the left was macerated (cold soaked) on the skins for 3 days, while the wine on the right had a 3-day cold soak plus spent a week on the skins during alcoholic fermentation. While the color from a photograph isn’t always indicative of what it looks like in real life, it gives you a good indication of the final color difference in the wines. The 3-day cold soak was more of an orange/salmon color. It wasn’t exactly rosé, but it wasn’t terribly unattractive either. It all depends on what the winemaker is looking for in their final color.

While Frontenac Gris doesn’t have anthocyanins in the pulp, there still tends to be a high amount of other colored molecules. I think the high quantities of these yellow/gold pigments mixed with a small amount of red yielded a wine that had more of an orange/salmon color.

Another great thing about using Frontenac Gris to make a rosé wine is that there are almost no tannins in the grape, thus by fermenting on the skins you don’t extract heavy amounts of tannins. Nonetheless, there can be bitter and herbaceous elements that are extracted from the seeds, or from the skin of fruit that is underripe.

Here’s the breakdown of the chemistry in the finished wine

TA  (g/L )                  pH                  Alc. %

Frontenac Gris – AF on skin

            9.20

            3.50

       15.4

Frontenac Gris – 3-day

          10.45

            3.41

       15.4

An interesting note from the fermentation on skins is the decrease in total acidity and the increase in pH. This could be due to some excess potassium extracted from the skins that may have facilitated tartrate precipitation as well as increasing the pH. Since we didn’t measure potassium, this is only a guess. However, the final chemistry of the two wines is pretty close.

As for how the wines taste, I’ll leave you with some of the tasting notes from our evaluation. The wines were tasted blind by our viticulture and enology crew.  Both of these wines were fermented to dryness and no adjustments were made post-fermentation. This was to ensure that they followed our standard protocol for winemaking. Some slight adjustments to the acidity or sweetness may have yielded wines that were a bit more balanced on the palate. You can see that there was some herbaceous character noted in the grapes fermented on the skins. Some tasters found it off-putting, while others enjoyed it. It is also possible that some fining could help remove some of these bitter compounds. In the end, I hope this trial at least gives you some tools to use in your own wineriess.  Cheers to some tasty rosé wines… just in time for summer!

 

Color (3-day cold soak pre-fermentation) salmon/orange
Aroma white chocolate, apricot, fruity, red fruit, artificial cherry, strawberry, berry, banana, hybrid, plum, soapy, some bakers spice, dried apricot, concentrated raisin, petrol/chemical
Palate acid, good citrus/peach flavors, some bitterness, tart, hot, different, red fruit, tart, berry, nutty, sour, peachy, berry, cloves

 

Color (Fermented on skins) dark pink, vibrant red, rose, pretty garnet
Aroma cherry, oregano, more riparia, lots of red hybrid, Frontenac flavors, herbaceous, blackberry, camphor, green pepper, cherry Robitussin, raspberry, cherry
Palate acid, hot, chemical, cherry, bitter, takes on more hybrid flavors, blackberry, black currant, herbaceous, thin, hybrid, underripe, red currants, cherry, plum, chokecherry, some bitterness, hot, cherry, raspberry, spice

 

 

Filed Under: Enology Tagged With: , , , ,

Passito… or Essencia?

November 11, 2011 by


Here is an update on my attempt to make a passito from Frontenac Gris…

After about 2 weeks of drying in the  greenhouse, the grapes had lost about 50% of their moisture. I decided to press them at this point, not knowing how well our tiny little hydropress would do with raisins! I had close to 10 kg of grapes (ahem, raisins) that I pressed, and got about 2.5 liters of “juice” from them (the consistency was more like syrup). I think a commercial press that went through a long series of slowly increasing the pressure might have gotten a bit better yield, but I was happy with what I got. The resulting juice/syrup was a deep amber to brown color. There was a slight copper tinge to it. We’ll see what the color is like after fermentation.

Now on to the most spectacular result…

At just 50% dehydration, I didn’t know what to expect for sugar numbers (I think typical passito is dried a bit further). However, I think I didn’t need to dry them out quite as much! The extracted grapes had a sugar concentration of 55 °Brix! That’s INCREDIBLY sweet! That’s the equivalent of almost 700 g/L (70%) of sugar. Coca-cola contains about 111 g/L of sugar. Maple Syrup contains 800-900 g/L of sugar. So… you can imagine how sweet this really is! The good news is that the Total acidity came in at 15.5 g/L, so I’m hoping that this will help balance the finished wine.

The problem with a wine containing 70% sugar is that the osmotic pressure is too great for most yeast to undergo fermentation. They find it difficult to transport waste across their cell membrane, so they die. There is one wine that I know of with an equivalent sugar content to what we achieved with this Frontenac Gris: Tokaji Essencia. This is a legendary Hungarian wine made from the juice that drips from dried, botyritis-infected berries. So, essentially, the free-run from botryitised raisins (if that makes sense). It has been known to reach 85% sugar in some years, but normally ranges from 50-70%. The other interesting thing about Essencia is that it can take 6-8 YEARS to ferment, and only obtains up to about 6% alcohol.

So, since I didn’t want to wait years to see what the final wine will taste like, nor did I want a wine with only 6% alcohol, I decided to add back a little bit of water to my Frontenac Gris. I brought it down to a still very respectable 45 Brix.

I started fermentation using a modified  pied de cuve method. I re-hydrated the yeast as one would normally do, but I used a larger quantity of water (I used 600 mL – the quantity I needed to dilute the wine to 45 brix). Then, I slowly added the syrupy goodness of the juice over a period of 24 hours. This allowed the yeast to slowly acclimate to their new (very harsh) environment, and ensured that my initial population of yeast was high. I used DV10 yeast because I know it’s pretty resistant (and it was on-hand). I would have preferred to use a yeast that is specifically made for ice wine/late harvest, but didn’t feel justified in ordering a whole package of yeast for this small quantity of wine. It seems to be fermenting nicely, regardless. I wonder how long it will take to finish… I’m excited to try it!

Filed Under: Enology, Just for Fun Tagged With: , , , , ,

Frontenac Harvest Data from 2001 – 2010

May 17, 2011 by
Here’s a look at some of our harvest data over the years for Frontenac. As you can see, we have a lot to deal with in order to try to balance the acids in this variety. For this reason, many people have found success making a fortified dessert wine or an off-dry to sweet rose-style wine with this grape. Frontenac was the first grape variety released by the U of MN explicitly for wine production. Although it’s chemistry differs from what we see with classic V. vinifera varieties, it has been shown to make some good wine. The previous enologist working at the U of MN has lots of experience with Frontenac (she even wrote her dissertation on it). Here is a link to an article she wrote for winemaking recommendations for Frontenac.
Filed Under: Enology Tagged With: , ,

La Crescent harvest data

May 2, 2011 by
A while back, when I first started this blog, I wrote a brief post about the grape variety La Crescent. At the time, I promised to compile our vintage data and put in some charts or graphs illustrating some of our data. Well, I’ve been trying to work out some cool charts that compare various vintage parameters, but it turned out to involve way too many factors and be too complicated to give any significant data. So, I’m just going to post our harvest data information below for now. As you are all well aware, we get some very high acidity in La Crescent (like the rest of our hybrids). Remember that wine with a TA > 10 g/L will taste sour, so it is important to use various deacidification techniques, or leave enough residual sugar to help balance the acidity. More on that in a future post…
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Terroir and Minnesota

January 27, 2011 by
I recently spoke on the notion of terroir and how it relates to Minnesota during the annual Minnesota Grape Growers Association (MGGA) meeting this past weekend. It is one of my favorite subjects when talking about wine, as this concept is what first brought me into the wine world, and what ultimately brought me back to Minnesota and our developing wine industry. The concept of terroir means that wines from a particular region are unique, and incapable of being reproduced outside that area, even if the grape variety and winemaking techniques are duplicated. When defining terroir, most people talk about how the geography and the soil relate to the taste of an agricultural product – in our case, wine. There is good reason for this, as the word terroir has its roots in the french word terre, which means earth/soil. However, the word terroir is much more complex, as it involves an interactive ecosystem between the climate, soil, geography, as well as all the aspects of human intervention with this environment.
Domaine Romaneé-Conti Grand Cru

As wine is an historical beverage that dates back to at least 6000 B.C., its development over time has close ties with human history. We know that early-on in wine history people recognized that wine coming from different vineyard sites had different properties. The Romans would stamp clay amphorae with the wine’s region of origin, and Benedictine and Cistercian monks in the middle ages dedicated much of their time to determining the best vineyard sites to make their wine. Their boundaries still exist today in the Grand Cru vineyards in Burgundy. A wine-grower in Burgundy will never say they make a Pinot Noir from Burgundy, but rather that they make a Burgundian wine from Pinot Noir. Though it seems like simple semantics, the difference between these two statements is actually quite substantial. To distinguish what makes them different gets to the very heart of trying to define the concept of terroir.

You see, a terroir is more than just a geographical place with geological and climatic influence. It also includes the types of vines that were planted, how they are planted, and every aspect of farming that goes into making the grapes as well as every aspect of vinification. The history of the place and even the way the wine fits into the local culture is important. When defining whether an agriculture product has terroir, the Institut National des Appellations d’Origine (the branch of government that regulates the A.O.C. system of the Agriculture department in France) uses the following definition:

A delimited geographical area defined from a human community who built over the course of its history a set of distinctive cultural traits, knowledge, and practices based on a system of interactions between the natural environment and human factors. The craftsmanship in play reveals originality, gives a standard, and permits recognition of products or services originating in this space and thus for the people who live there.

Thus, terroir is as much about the culture and history of the people who live in a place as it is the factors of the natural environment. Which, raises the question of whether it is possible to have a true terroir in Minnesota. We have a burgeoning wine industry where, in 2007, two-thirds of the vineyards planted in the state were less than 4 years old. We have 10 major varieties that are being planted, and generally have no consistency in style for the wines made with these varieties. Most wineries source fruit from many different vineyard locations across the state, and often across the country to create blends that do little to show the typicality of a certain area. Although I realize that there are socio-economic factors driving this decision to buy out-of-state fruit, the very fact that wineries themselves aren’t embracing the notion of terroir means that we will never achieve it in our state.
One may ask why this matters – who really cares if our wines come from grapes grown in the state or not? As long as the wine is good, right? In the short run, making “branded” wines or vin d’effort (wines which owe all their characteristics to the effort of the winemaker rather than terroir), may prove successful for a variety of reasons. However, history has proven that the wine industry is boom and bust, and in the long run terroir wines end up surviving.


Take the example of the area around La Rochelle, France. During the middle ages, it had a booming wine industry. Located on the western coast of France, its harbor allowed for quick shipment of wine from France to Great Britain and Holland. Along with the nearby city of Bordeaux, it had access to a large consumer base, and a way to transport the wine to them. However, over time the economic significance of a port became less and less important. Environmental conditions (soil and climate) as well as the varieties chosen to cultivate in Bordeaux produced a wine of much higher quality. Thus, the wine industry in La Rochelle decreased with the decline of the port, while that of Bordeaux continued to flourish.

For one more example, I’ll point to the fact that the area around Paris had a booming wine industry in relatively recent times. In 1820, 4.8 million hectoliters of wine were being made from vineyards surrounding Paris. Compare that to the current production of 5.2 million hectoliters in Bordeaux, and one can see how significant this industry really was. Wineries around Paris had it easy: they had the largest consumer base in France right in their back yard. However, as soon as a railway was built linking Paris to Lyon and Marseille, it was possible to ship wine from the South of France to Paris. When phylloxera wiped out most of the vineyards in Europe, the vineyards around Paris were not replanted. Once again, vineyards planted where conditions favored high-quality wine production survived, while those that didn’t failed.
But what about regions where environment doesn’t favor the production of high-quality table wine? This is where the human factor comes in. I’ll point to the area of Champagne (just because it is the most well-known). It can be argued that the climate and soil of Champagne are not ideal for making wine. In fact, the vineyards of Champagne were at one time a garbage dump for much of Paris and Reims well into the 20th century. They were using the trash as compost. One can still walk the vineyards in Champagne and find bits of plastic and broken dishes in the soil. Its climate also makes it difficult to achieve optimum ripeness in grapes every year. Now, much has been written about the “invention” of Champagne, but the fact remains that the wine exists because the acidic, unripened fruit from these northerly vineyards makes hardly an ideal table wine. The cold winters made fermentation difficult, and re-fermentation in the bottle in springtime was normal in a time when sterile filtration and sulfur addition was non-existent. Eventually, small changes over time led to people purposefully allowing the wine to undergo a second fermentation in the bottle.  I realize this is a very simplistic discussion on the finer points of the history of this great wine, but the point is that this wine style developed because of decisions that a group of humans made based on their interactions with the surrounding environment. If it were only a single winery in Champagne that developed this style, I would argue that we wouldn’t associate the word “Champagne” with sparkling wine today. This emphasizes the importance of the human factor in the concept of terroir.
There are many examples throughout history that are all very interesting and intriguing, and I could go on (Hunter Valley Sémillon, New Zealand Sauvignon Blanc, Vin Jaune, Saint-Bris…) but as this post is possibly too long to contain the attention of the vast number of people reading it, I will try to come to a conclusion. Does Minnesota have a terroir? Not yet, maybe we never will. It is something that develops over time. How long, you ask? That is the most difficult question to answer. As we have seen, terroir develops when a group of people in a given area collectively decide to make wine in a certain style, using certain varieties, and certain viticultural and enological practices. I think the key word there is collectively. This will be a huge obstacle to overcome in Minnesota, as our culture was founded on individualism. Unlike Kantian philosophy that shaped continental Europe, we went the way of John Stuart Mill. We value our individual freedom, and believe we don’t have to adhere to general rules and principles. This sense of individualism is what drives innovation in our country. It is what, to some degree, makes us exceptional. It is also the driving force behind the Minnesota wine industry at present. However, I believe in the long-run, it may hinder our success in becoming a unique region. One of the keys to growth in our industry will be to garner acceptance within our community, and eventually in the wider market.  This, I believe, is possible. Because Minnesotans are very proud of our state, acceptance within Minnesota is easy. We love all things Minnesota. However we need to raise consistency and quality of the wines we produce to be accepted into the larger wine community. I’m hoping this blog is the start of a dialogue between growers and winemakers in Minnesota, as well as with the researchers at the University, so we may collectively advance our industry forward.
Filed Under: Just for Fun Tagged With: ,