Mourvèdre: A Tannic grape for many wine styles

We called it the “Mighty Mo” and whether or not it was inspired by the great World War II battleship, the USS Missouri, I can’t really remember. The year was 2002 and I was working the harvest season in the Sierra Foothills of California. Our entire complement of inside tanks were open top fermenters that required a hand punch down. But tucked back in the corner was my first experience with the red grape Mourvèdre. Working in that corner always made me crave the biggest, juiciest hamburger on the planet. Punch down after punch down this was the case. And then the cravings went away after we pressed and barreled down the tank. Unbeknownst to me at the time that this was a specific characteristic of Mourvèdre, not the part about the cravings, that was secondary, but that meatiness, or broth-like aromas are some of the descriptors used to describe the wines made from it. I learned a lot from that first experience — from how to ferment in a way that doesn’t bring out the sometimes astringent tannins, to how to incorporate the wine into the final blend. A skill set that was so important to my early winemaking experience.

The Vitis International Variety Catalogue lists 100 synonyms for Mourvèdre. Most of the names take on a local meaning to either the variety’s origin or local area where it is grown. The closest explanation of the name “Mourvèdre” is that where the grape was grown in eastern Spain is the old village of Murviedro (now Sagunto). When the grape was introduced in Southern France it took on the name of its ancestral village in Spain, which was locally known as Monastrell. Another name for which the same grape is known for is Mataro. It was not known until recent advances in DNA mapping that all the names were for the same grape. Mataro holds significance in Australia, California, and Portugal. In California, Mataro was introduced sometime after the Gold Rush of 1849. In the same DNA investigations it was determined to be one of the grape varieties that comprised the old heritage vineyards established to quench the thirst of the growing state.

From a grape growing standpoint, this variety likes warmth. Plantings are best on sun exposed slopes, and soils that are able to hold some moisture, but not overly moist which promotes more vegetative growth. The ideal soil type is shallow clay. The variety is best when coupled with a low leaf area-to-fruit ratio. It is late to bud and subsequently late to mature, which limits its range in the Northern Hemisphere to no further north than Châteauneuf-du-Pape region in the Southern Rhône Valley (~ 45° North) in France, about the same latitude as Eastern Washington State (~ 46° North) in the US.

Mourvèdre has small berries on an equally small cluster. These small, dense clusters can make the variety susceptible to powdery or downey mildews if a good spray program is not maintained prior to the closure of the cluster after veraison. The skins of the berries are thick and can lead to wines with intense color and high tannin content. The selection of winemaking style with this grape helps bring out the best, and sometimes the worst if not done properly.

The wine styles of Mourvèdre are varied. In Southern France, it is a popular component in rosé wines. The warm Mediterranean summers just beg for a refreshing glass of crisp rosé. The winemaker must pay particular attention to time and temperature when making the rosé-style wine. Given the good promise of color, keeping the soak temperature low to keep fermentation from starting is important, but winemakers must also frequently be checking progress of the color extraction. The skin contact time could be as little as an hour, but generally not more than 24 hours so that the astringent tannins stay with the skins after the juice is removed. The juice can be removed via a simple decanting or draining, or with the use of a soft press cycle. By soft, I refer to low pressure in a bladder press if one is available. The idea is to not rupture the skins so that they give more tannin to the wine. Some winemakers resort to the use of enzymes and a very short maceration period. However you choose to get this juice, ferment at low temperatures, say 55–60 °F (13–16 °C). Your yeast choice is up to you, choose a white wine yeast or one that is specific for rosé. In any case, ferment the juice until dry (< 2 g/L residual sugar) and you will see why rosé is such a popular wine style in France.

The red wines produced from Mourvèdre take on the characteristics of the region it is grown. The length of the growing season contributes to tannin development in the berry on the vine. Sunlight is the key, but it is equally important to watch out for its dehydrating effects resulting in high sugar levels that can lead to very high alcohol wines. The risks of high alcohol are stuck or sluggish fermentations or yeast producing off flavors, not to mention the sensory component in that the wines won’t take on the variety’s true varietal characters of meaty, bullion, or earthy as the alcohol affects taste perception.

But many red versions of Mourvèdre are produced and the winemaker needs to choose what is best for their specific grapes. This often comes in the form of local traditions. The producers of lighter tannin wines, for example those grown at the latitude extremes where the growing season can be cut short in the fall, will ferment the grapes with the stems to help facilitate tannin structure. Stem and skin contact are monitored closely to avoid over-extraction of perceptibly green vegetal characters.

In Spain, California, South Africa, and Australia, the grapes are generally processed through a de-stemmer/ crusher, akin to a standard red wine fermentation. My personal experience is consistent with that only that we did not close the crushing rollers completely. We allowed some intact berries to pass through. This can lead to a brighter fruit expression in the wines due to the intra-berry fermentation, which gets expressed when pressing. Basket presses can be inefficient in the process of breaking berries. I have known of some winemakers that will run the fermented must through the crusher rollers, only this time with the gap narrowed to insure the berries release their contents. Keep in mind that this can rough up the berries and your tannin expression may be increased.

From a winemaker’s standpoint, you are always trying to achieve the best possible wine. With a variety like Mourvèdre, the tendency for bitter or astringent tannins is there, but that might be the desired result. If it is not, then blending is the best approach.

The fact of the matter is that blending is exactly what many winemakers of past and present have incorporated Mourvèdre into. In the south of France, it is accompanied with Cinsault and Carignan. This has proved to be a successful blend. This is a varietal combination the rosé lovers and red wine lovers alike can agree upon! The other main blending partners with Mourvèdre are Syrah and Grenache Noir. GSM branding is the strong point in Australia. The Châteauneuf-du-Pape wines are also of the GSM nature, however they are mostly blends in which Grenache is the majority stakeholder. There are 13 permitted red grapes in Châteauneuf-du-Pape and some producers try to use all of them. Mourvèdre is not a major player. In the US there are no rules other than whether the wine would be labeled as a varietal, which in this case is at least 75%. Mourvèdre’s market share as a varietally labeled wine is very small.

When blending, the winemaker needs to focus on the best needs of the wine at hand. For the rosé fans, you evaluate if the individual rosés are “self sufficient.” Depending on your degree of tannin extraction in the color extraction phase, you blend accordingly. Face it, when you decide to make a rosé, the stage is already set. If you had too long of a soak phase, then that would result in some apparent bitterness and/or astringency from the tannins, or perhaps the color intensity was too much. Blending this rosé with something like a Grenache rosé might be the key to the perfect rosé. With respect to blending red wines, this is a trial and taste proposition. Tasting the individual components and ranking them for their positives and negatives and then writing down your goals of the final wine.

If you have a tannic Mourvèdre and you insist to keep it “pure,” or your options for blending are limited, then the winemaker should consider fining trials. My experience is primarily with egg whites (albumin).

I never did get that burger inspired by “Mighty Mo.” But I still think about it now almost 15 years later. We didn’t produce a varietally labeled Mourvèdre, rather this was one of the secrets in our Rhône-based blend. I think back on the low yields that made that wine so beautiful and it was such a textbook example of the problems that can be associated with it. The low yields were the result of mildew issues in the field, the high quality, however, was the result of the low yields. Every winemaking experience should be a learning experience. It is what you learned and what you can take forward with you that matters most.

Mourvèdre Recipe (5 gallons/19 L)

This is a recipe that will allow you to make an additional 1 gallon (3.8 L) of rosé wine. (Based on yield assumptions of 120 gallons/450 L per ton of fruit).

125 pounds (57 kg) Mourvèdre grapes
10% potassium metabisulfite (KMBS) solution. Weigh 10 grams of KMBS, dissolve into about 50 milliliters (mL) of distilled water.
When completely dissolved, make up to 100 mL total with water.
5 grams Lalvin EC1118 yeast
1 gram Laffort Actiflore® Rosé yeast (Lallemand D-47 can be used as an alternative)
~7 grams di-ammonium phosphate (DAP)*
~7 grams Go-Ferm*
~7 grams Fermaid K (or equivalent yeast nutrient)*
Malolactic Fermentation Starter Culture (CHR Hansen or equivalent)
*Amounts are approximate. Add these nutrients based on the addition rate of one gram per gallon of juice.

Other equipment or needs
15-gallon (57-L) food-grade plastic bucket for cold soak/fermentation.
5-gallon (19-L) carboy
2-gallon (8-L) carboy and/or (3–4)
1-gallon (4-L) jugs
Racking hoses
Colander or strainer
Wine press
Inert gas (nitrogen, argon, or carbon dioxide)
Clinitest tablets
Ability to maintain a must temperature between 40–86 °F (4–30°C) depending on cold soak/fermentation option.
50 mL graduated cylinder
Pipettes with the ability to add in increments of 1 mL
Tartaric acid (addition rate is based on acid testing results)

Must and Juice Preparation
1. Clean and sanitize all of your winemaking equipment prior to use at any step in the process.

2. Crush and de-stem the grapes. Transfer the must to your food-grade plastic bucket.

3. During the transfer, add 23 mL of 10% KMBS solution (this addition is the equivalent of 50 mg/L (ppm) SO2). Mix well.

4. Take a sample to test for Brix, acidity, and pH. Keep the results handy. We’ll take this up later.

5. Layer the headspace with inert gas, keep covered, and begin lowering the temperature. After approximately 4–6 hours, use the colander/strainer to remove a small juice sample to check the color. The degree of color extraction is your choice. If the juice is not the color of your liking, wait a little longer, and check again. It is not recommended to let the color extraction phase for the rosé option exceed 24 hours.

6. When the desired juice color is reached for the rosé option, use the colander to remove about 2 gallons (4 L) of the juice. Place the juice in your 2-gallon (4-L) carboy and continue to keep cool. Place an airlock on the container. We’ll come back to this.

Red Wine instructions (24 hours later)
1. Begin to warm the must to ~70 °F (~21 °C).

2. Sprinkle 5 grams of Fermaid K on the must and mix well.

3. Go back to those lab results you took yesterday. Typical Brix for this style is 24–25 °B. Typical pre-fermentation acid levels will be 5.0 to 7.0 g/L, possibly as low as 4 g/L in some warmer climates. Adjust as necessary using tartaric acid to pre-fermentation level of 7.5 to 8.0 g/L. Don’t worry here; the malolactic conversion will drop the acid levels. Slightly higher acid won’t hurt here.

4. Prepare yeast. Heat about 50 mL of water to 108 °F (42 °C). Pitch the yeast when the suspension is 104 °F (40 °C). Sprinkle the yeast on the surface and gently mix so that no clumps exist. Let sit for 15 minutes undisturbed. Measure the temperature of the yeast suspension and of the juice. You do not want to add the yeast to your cool juice if the temperature of the yeast and the must temperature difference exceeds 15 °F (8 °C). To avoid temperature shock, acclimate your yeast by taking about 10 mL of the juice and adding it to the yeast suspension. Wait 15 minutes and measure the temperature again. Do this until you are within the specified temperature range. Do not let the yeast sit in the original water suspension for longer than 20 minutes.

5. When the yeast is ready, add it to the fermenter and mix.

6. You should see signs of fermentation within one to two days. This will appear as some foaming on the must surface and it will appear that the berries are rising out of the medium. This is referred to as the “cap rise.”

7. You need to have on hand the ability to push the grapes back into the juice to promote color, and tannin extraction. This is called “punching down” and this should be done three times per day.

8. Monitor the Brix and temperature twice daily during peak fermentation (21 down to 10 °Brix). Morning and evening is best and more often if the temperature shows any indication of exceeding 86 °F (30 °C) in which case you would activate your cooling system. Keep the temperature between 81–86 °F (27–30 °C).

9. At about 19 °Brix, dissolve 5 grams of DAP in a small amount of water and add to the must.

10. Taste regularly through the fermentation to determine if the tannins are extracting too quickly. If the astringency is high, you can consider pressing early, if you have the color you wish to achieve. Early pressing can work for such a small batch processed.

11. If you haven’t pressed, when the Brix reaches zero (about 5–7 days), transfer the must to your press, and press the cake dry. Keep the free run wine separate from the press portion for now and label each.

12.Transfer the wine to your carboys or 1-gallon (4-L) jugs. Your press fraction may only be a gallon or two (4–8 L). Make sure you do not have any headspace.

13. Inoculate with your malolactic (ML) bacteria. Check the manufacturer’s instructions on how to prepare and inoculate. Cover the tops with an airlock to allow the carbon dioxide (CO2) to escape.

14. Monitor the malolactic fermentation using a thin layer chromatography assay.

15. When the ML is complete, add 2 mL of fresh KMBS (10%) solution per gallon (4 L) of wine. This is the equivalent to ~35 mg/L (parts per million) addition.

16. Measure the pH and titratable acidity (TA). Most importantly you want a finished TA of about 6.0–6.5 g/L. The pH is secondary but should not be over 3.7. Consider adding acid to adjust the TA prior to settling, but taste the wine first to make sure it is not too tart. Do not add any more acid if the wine is too tart.

17. Place the wine in a cool place to settle.

18. After two weeks, test for sulfur dioxide (SO2) and adjust the SO2 as necessary to attain 0.8 ppm molecular SO2. (There is a simple SO2 calculator at www.winemakermag.com/sulfite calculator). Check the SO2 in another two weeks and adjust. Once the free SO2 is adjusted, maintain at this level. You’ll just need to check every two months or so, and before racking.

19. Rack the wine clean twice over 6–8 months to clarify. Consider during this period using some oak chips to add oak flavors, but don’t expose the wine too long to the oak: 1–2 weeks is sufficient for this volume. Sample it frequently so you don’t over-oak it.

20. Once the wine is cleared, it is time to move it to the bottle. This would be about eight months after the completion of fermentation.

21. Make the project fun by having a blending party to integrate the press fraction back into the free run. You may not need it all, use your judgment and make what you like.

22. If all has gone well to this point, given the quantity made, it can probably be bottled without filtration, but if you decide filtration is needed go ahead. Maintain sanitary conditions while bottling.

Rosé instructions (24 hours after juice preparation)
1. Begin to warm the rosé juice to ~65–68 °F (18–20 °C).

2. Go back to those lab results from step 4. Typical pre-fermentation acid levels will be 5.0 to 7.0 g/L, and in some warmer climates, possibly as low as 4 g/L. Adjust as necessary using tartaric acid to pre-fermentation level of 7.5 to 8.0 g/L. Slightly higher acid won’t hurt here.

3. Add two grams of Fermaid K to the juice (1 gram per gallon equivalent)

4. Prepare yeast. Heat about 50 mL distilled water to 108 °F (42 °C). Measure the temperature. Pitch the yeast when the suspension is 104 °F (40 °C). Sprinkle the yeast on the surface and gently mix so that no clumps exist. Let sit for 15 minutes undisturbed. Measure the temperature of the yeast suspension and of the juice. You do not want to add the yeast to your cool juice if the temperature of the yeast and the must temperature difference exceeds 15 °F (8 °C). To avoid temperature shock, acclimate your yeast by taking about 10 mL of the juice and adding it to the yeast suspension. Wait 15 minutes and measure the temperature again. Do this until you are within the specified temperature range. Do not let the yeast sit in the original water suspension for longer than 20 minutes. When the yeast is ready, add it to the fermenter.

5. Initiate the fermentation at about 65–68 °F (18–20 °C) and once fermentation is noticed (~24-36 hours), move to a location where a 55 °F (13 °C) temperature can be maintained.

6. Two days after fermentation starts, dissolve the DAP in as little water required to completely go into solution (usually ~ 20 mL). Add directly to the carboy. Addition rate should be dosed at one gram per gallon (4 L).

7. Normally you would monitor the progress of the fermentation by measuring Brix. One of the biggest problems with making white or rosé wine at home is maintaining a clean fermentation. Entering the carboy to measure the sugar is a prime way to infect the fermentation with undesirable microbes. So at this point, the presence of noticeable fermentation is good enough. If your airlock becomes dirty by foaming over, remove, clean, and replace it as quickly and cleanly as possible. Sanitize anything that will come in contact with the juice.

8. Leave alone until bubbles in the airlock are about one per minute (usually 2–3 weeks). Then begin to measure the Brix every 2–3 days.

9. The wine is considered dry, or nearly dry, when the Brix reaches -1.5 °Brix or less.

10. When the fermentation is complete, add 2 mL of fresh KMBS (10%) solution per gallon (4 L) of wine and mix.

11. Let settle at 40 °F (4 °C) for two weeks, then rack off the gross lees to another appropriately sized container.

12. Test for pH and SO2 and adjust as necessary to attain 0.8 ppm molecular SO2. Check the SO2 in another two weeks, prior to the next racking and adjust while racking.

13. When the sulfur dioxide levels are stable, fine or filter if desired and then you are ready to bottle. Be sure to maintain sanitary conditions while bottling. Once bottled, periodically check your work with friends.