Why We Use Cork in Our Winery

Cork is a sustainably harvested product that is natural, renewable and recyclable.  Cork forests support high levels of biodiversity and prevent desertification in the Mediterranean region , where most of these forests are found. Additionally, cork oak trees store carbon in order to regenerate their bark.  According to WWF, a harvested cork oak tree absorbs up to five times more carbon than one that is not, and cork forests absorb millions of tons of CO2 each year.  With a global decline in the natural cork use for wine, cork trees are being lost and countries are experiencing desertification, which also threatens the habitats of some critically endangered species, like the Iberian Lynx in Portugal.

Let's start with a brief summary of the types of wine bottle closures:

Natural Corks
Natural cork has several advantages, it is a natural product, it is porous and traditionalists will say that cork creates the perfect oxygen/wine ratio for cellar aging. The oxygen transfer rate of natural cork is approximately 0.0179 mg/L or between 3.00 and 6.83 micrograms of O2/day. Cork is also recyclable and cork forests contribute to biodiversity and prevent desertification of the Mediterranean region. A high quality cork offers long term aging potential, though with very high end wines it is recommended to re-cork after 25 years, as the cork will start to fail at that time.

But there are some major disadvantages, including problems with leakage as well as sources of off-odors. Leakages can be caused by structural imperfections of the cork itself, of it could be caused by wrongly aligning the cork and bottle during the corking process. Rapid temperature changes may also cause leakage. Another serious problem with cork is the possibility of off odors, including TCA (Trichloroanisole), as well as microbial growth from a variety of sources.

Concerns about structural imperfections of corks as well as cork taints have been the major reason for the development of alternative closures.

Synthetic Corks
Synthetic corks are inexpensive, they are consistent and they will never have the taint issues of real cork. They can also be used without the need for new bottling equipment. However, plastic allows the diffusion of oxygen at varying levels, ranging from 0.0052 cc/day to 0.0076 cc/day, while other evaluations of synthetic cork show diffusion from 5.7 to 13.99 micrograms of O2/day. Oxidation of wines under a synthetic cork can be observed as early as in a year, though ongoing research is addressing this issue. Plastics are not generally a renewable resource.

Screw Caps
Metal screwcaps are a major alternative to cork when it comes to closures. The metal cap itself is not the actual closure; rather the bottle is sealed with a plastic foam pad that is either lined with saran and a tin layer, or saranex only. A main advantage of these closures is that they are very consistent; they are great at retaining SO2 and they minimize oxidation. They are pilfer proof, and eliminate the need for a cork screw. There is no risk of TCA and the bottles do not need to lie on their sides.

There is some research suggesting that screw caps may lead to reduction in wine (the opposite of oxidation.) And there is still disagreement as to the aging potential of wine closed with a screw cap. Another disadvantage is the cost of investing in a capping machine, which starts around $8000. The various types of screw caps in the market are not standardized so a capping machine is specific to one type of screw cap only.

"Engineered" or "Technical" Corks
A technical or engineered cork is basically made of shredded natural cork that is then “glued” back together and molded into the traditional cork shape. This type of cork provides all the advantages of natural cork, but eliminates the problems of cork taint (from musty smells to TCA) and inconsistencies with oxygen permeation caused by technical imperfections. Different grades of cork are used in this process, which - just as with the natural cork - influences the number of years that the cork is guaranteed for. This typically ranges from 2, 3, 5 and 10 years.

Regarding overall market perceptions, cork closures are still the preferred method of closures in the US for all wines, but even in countries where alternative closures are well accepted, many wineries opt to use traditional cork closures.

When deciding about the best wine closure, the overall environmental impact should not be underestimated! Cork is a sustainably harvested product. It is produced primarily by the Cork Oak (Quercus suber), but the tree does not get cut down in order to harvest the cork. The cork oak is the only tree, where all the bark can be stripped without harming the trunk. Harvesting cork starts when a tree is around 30 years old, and is repeated every 10 years or so - for about 200 years per tree.

We know that by using natural cork, we are helping save cork trees in Portugal, across Europe, and in the Mediterranean region!

Here are some links where you can learn more about how corks are sustainably harvested and the importance of cork trees:

Cork Forest Conservation Alliance

"Save a Tree, Use Real Cork" The New York Times, 2013

Cork Quality Council

Labeling Wine Bottles

Every new wine label needs to be approved by the federal  Alcohol and Tobacco Trade and Tax Bureau, TTB for short. (Wine labeling rules are found in Title 27 of the Code of  Federal Regulations) After the approval, they can be printed and applied.  We use a manual labeler, which we really like:

Pressing Apples

We were fortunate to get 2 bins of apples, including Gala and Yellow Delicious this past week.  This was a bit more than we had anticipated, about 75 bushels and luckily we had lots of helper this weekend!

We used our antique apple press  (literally over 100 years old, but upgraded with an electric motor) to shred the apples, which were captured in food grade, sanitized buckets. Though the old apple press can be used for pressing, the capacity is so small that it would have taken us days to get this done.

For pressing, we use our wine basket press instead.  And just as we would with grapes, we added rice hulls to the shredded apples, to increase the efficiency of juice extraction without the danger of pressing stems or seeds.It took all afternoon and late into evening before we had them all processed.

It made a lot of cider!

1st Corot-Noir Harvest

Our first Corot Noit harvst turned out to be rather sparse.  Not only was it the first year that the vines were producing, but we had pruned a lot of clusters off to ensure the vines stayed healthy through the dry summer conditions.  But on top of all that, we had major bird damage - the story of our 2016 harvest season.

For these grapevines, we had used black netting, since it is a lot more aesthetic to look at - sadly, the black netting was completely useless.

We picked just enough grapes to end up with 2.5 gallons of must (we had been hoping for ten times that much).  Since we had so few grapes, we destemmed them manually, and then crushed them by hand.

We let fermentation run its course, punched down the cap every day, and ended up with 1.5 gallons of wine.  We'll see how it turns out in about a year.  For 2017 we are hoping for a full barrel!

Another Bottling Day

We took advantage of a long weekend to do another bottling run - with just three of us we bottled our 2014 Chambourcin and 2014 Rosè.  Not counting set-up and cleaning before and after, it only took us about 4 hours to bottle. Everything together took about a day with extra helpers.  Fortunately, we had no equipment breakdown and only broke two bottles during corking (go Lars!)

Wineberries?

One of the "must have" bramble varieties for a budding winery has to be the wineberry - Rubus phoenicolasius, also called Japanese Wineberry, or Wine Raspberry (see Wikipeadia for more info)  It is a native species in China, Japan and Korea and was introduced to North America in the late 19th century for breeding new hybrid raspberry varieties.  These berries are very tasty, with a more intense raspberry flavor than raspberries themselves.  Wineberries are sweet but also tart, and the higher level of acidity is what makes them so good for jams and for wine.

Wineberries now grow wild in parts of the United States, primarily in the Appalachian Mountains - and they certainly grow around our region!  They are commonly found  along the edges of fields and roadsides, but are not widely cultivated.  Actually, wineberries are considered an invasive weed in many states, including Pennsylvania.There is a great blog post on the Cumerland County Extension website about wineberries.

What makes this type of bramble so unique is the way that the berries ripen inside a calyx – a remainder of the flower.  The calyx folds back as the fruit reaches maturity and a shiny, slightly sticky and very tasty berry emerges.

Despite the fact that these berries are not widely cultivates, we dug some out this weekend and planted them in a new row, next to a row of red raspberries.  We'll see how cultivation affects these berries.  Hoping that we can contain them in a neat row and that they bear a lot of fruit.  Can't wait to make some jam and maybe some wine as well.

Eastern Winery Expo

Jens and Tina each took a day off work to attend one day of the Eastern Winery Exposition - which is held in Lancaster every other year (the odd years are held in Syracuse).  We split up for the educational sessions, so that we could cover the double track of seminars.  Luckily we did, as there was a lot of good information! We also had time to walk through the exhibit area and talk to a lot of vendors.

Sessions that were especially useful were a track dealing with the chemistry, processing and fermentation of fruit wines; and a session devoted entirely to Chardonel,
which is a variety we recently planted.  Other sessions dealt with filtering protocols for winemakers, and fungal disease prevention in the vineyard.

We ran into several winery owners we knew, met new ones and also met several of Tina's former "classmates" from the HACC enology/viticulture program. Definitely a worthwhile day!

Sauterne - a Wine worth Trying

One of the typical white wines from the southern part of Bordeaux is Sauterne. This sweet white wine is produced in the five small villages that make up the Sauternais appellation in Bordeaux, south of Graves. Sauterne is typically made from a blend of the two white Bordeaux grapes: Sauvignon Blanc and Semillon. Sometimes Muscadelle grapes are also included, usually at less than 3%.

The sweetness of Sauterne is not from a late harvest, but rather from botrytis, or Noble Rot, which develops during cool humid nights and warm, dry days at time of maturity. These humid conditions develop because the two rivers in this area, the Ciron and Garonne, have different temperatures, which cause the misting phenomenon.

The botrytis dries out the grape berries which leads to a concentration of flavors and aromas, as well as a concentration of sugar, which are the foundation of a very rich, full bodied, incredibly flavorful wine.

The botrytized grapes are hand-selected, hand-harvested, pressed, and fermented. Their high sugar levels causes the alcohol level to reach as high as 15% to 16%, at which point the yeast cells die. Fermentation ends with as much as 7% residual sugar!

Sauterne is usually aged in oak, anywhere from 18 months to 3 + years before bottling. Bottles can be consumed young, or aged for many years. The longer it is aged, the more amber the color and the more complex the flavors.

Sauterne is a very rich, sweet wine that is balanced by high levels of acidity. Aromas include honey, melon, pineapple, mango, papaya and dried apricots. It can be very complex and flavorful, and it is serves as an aperitif as well as dinner or dessert wine. Because of the time consuming harvest and production, Sauterne is one of the most expensive wines, and often under-appreciated.  Here is a link to a recent article in the NYT about this specialty wine.

Terroir - on a Rudimentary Level

Terroir is a French word, which means land – but in the context of wine, terroir refers to much more than the actual land, it encompasses all the aspects that influence grapevine development and fruit ripening potential, from the nutrients in the soil, drainage, the climate, elevation, predominant wind directions, humidity – even other plants grown nearby. Terroir’s definition may also include decisions made by people, such as traditional row and vine spacing, and pruning techniques.

All of this will greatly influence the characteristics of the end product - the wine – from the flavor profile to alcohol levels (which in turn depend on the level of brix at harvest).

Terroir is an important consideration when studying wine, as each region's terroir – even as small as microclimates within the same vineyard – will affect how the wine ultimately tastes. Wines from the same grape variety will therefore taste very differently, based on the terroir of the vineyard from where the grapes came.

Some very basic examples would include a grape variety grown in a warm climate vs a cooler climate, as the flavor profile will be very different. For example a Pinot Gris from a cool climate may have flavors of pear or apple, while a Pinot Gris from a warmer climate (where the grapes had a longer ripening season) would have flavors of peach or melon. Terroir is also the basis for the French appellation d'origine contrôléede (AOC) system.

Grape Harvest 2015

We had a great grape harvest this year - weather conditions were perfect and harvest parameters were great for each of our varieties.

We started with our Concords, which we picked  over several days during the last week in August.  We sold most of them at the local fruit auction.  On August 30th we picked the last of them and pressed them for juice (some of which we fermented for some wine experiments).

Nothing beats fresh Concord grapes and juice!

We harvested Chambourcin grapes from our young vines on September 7 (Labor Day)- a bit early, as we are going to try and make some rose wine from these.

On September 13 we picked all of our Vidal Blanc grapes.  This was our first harvest from these vines and we are looking forward to some white wine experiments.  Next year, we should have a lot more as the vines mature.

And finally on the weekend of September 19 and 20, we picked the remaining Chambourcin grapes.  It kept us busy all month!  Now comes the clean up of the bird netting, the harvest bins and all equipment maintenance.

Major Equipment Overhaul

We took our crusher/destemmer to get sandblasted and then had it re-coated.  All the bearings were replaced in it as well.  It looks brand-new and runs like a finely tuned machine :)

Newly coated stand for
the Crusher-Destemmer 

Newly coated
Crusher-Destemmer

We also took our basket press apart and Jens made new oak slats from scratch, which Jeff sanded and coated with several layers of food grade finish.  All crush pad equipment underwent its annual maintenance regiment as we prepare for harvest 2015!!.

Basket slats are drying in
the tractor shed

Assembly of basket started

Chambourcin Harvest - Take Two

We picked the majority of our Chambourcin two weeks after having picked the first batch (the grapes we used for the rosé wine).  Luckily we had loads of helpers - big and small, and we ended up harvesting the remaining grapes in just a few hours.

Toben

Fiona

 

Leif

They were beautifully ripe, amazingly sweet grapes that should make a great wine!  We destemmed, crushed and sorted the grapes before dumping them into the fermenting tank.

This year, we were much more prepared for making wine and had all the necessary "ingredients" and lab equipment ready.  We also decided to use the same type of yeast for all our wines.  Check out this block of yeast:

Update on the Rosé Experiment

Surprisingly, both of the 3 gallon carboys full of  the "sludge" that had settled out of the pressed juice, did clear somewhat.  We were able to rack off another 2 gallons into the fermentation tank - the rest of the "sludge" went to the compost pile.

Fermentation of the soon to be  rosé wine is now well under way, and we'll be monitoring it daily until it reaches completion.    Stay tuned :)

The Makings of Rosé

There are a couple of options for making a rosé, including blending different wines together, but we opted for using red grapes and basically processing them just like a white wine.  

With other words, we picked the grapes, ran them through the crusher/destemmer and the put them into the press.  We collected all the free run juice first (about 40 gallons), and then started to gently press the grapes for another 5 gallons, which were added to the free run juice.  We continued pressing the grapes, but kept this juice separately - which yielded about 7 gallons.  Toward the end of pressing, the juice had a distinct “vegetative” flavor, from the bits of stems and seeds that got crushed – not nearly as pleasant tasting as the free run juice.

ice bag floating in the fresh juice

We cooled the juice by dropping previously frozen and sealed ice bags into the wine, to keep the temperature around 65° F. 

After treating the juice with SO2 and adding Pectinase, we covered the barrel and let the juice sit overnight.  This should help with settling out impurities.  We also took a juice sample to test the pH, sugar level and TA (total acidity).

Today we racked the clear  juice into a new barrel - you can see the rose colored juice being pumped through a clear hose in the left picture.  There was a surprising amount of "sludge" left near the bottom of the barrel, nearly 5 gallons.  We racked the sludge into two small carboys to see if it would clear anymore (I just don't see how it could).

We did the same with the 7 gallons of pressed juice, added the hydrated yeast to both containers and let the fermentation begin!

Harvest with Upgraded Grape Equipment

We harvested over 750 lbs of our Chambourcin grapes this morning to experiment with making rosé wine.  This relatively small harvest served a double purpose:  to try and make rosé, and to make sure our new (used) grape processing equipment will work as we hope before be pick the bulk of the grapes later this month.

We got an early start, the fog had not even lifted, and it was still pleasantly cool.  First order of business:  remove the bird netting:

  

nice cluster!

We alternated picking and crushing/destemming, then dumping the   grapes into the press.  All this took five of us about two and a half     hours, plus another half hour for clean up.

The used crusher/destemmer we got earlier this summer worked surprisingly well.  Jeff had to rewire the barn in order to get a 220 V outlet, and a friend build us a stand for underneath the destemmer, which made it a lot more sturdy.  Yesterday we scrubbed everything again with soapy water, then power-washed it prior to using it today.  Here is a video showing how it worked:

We then dumped the crushed grapes into the press, and collected the free run juice first.  This will be the juice we use for the rosé wine.  We then pressed the grapes and collected the pressed juice for a separate batch of wine.  

Meet our Basket Press

Our latest equipment upgrade was a used "Zambelli" basket press with a capacity significantly larger than anything we had ever used before.

We actually found this on Craigslist - in Maryland (and pulled it on a trailer across the Bay Bridge).

Not only does this press have larger capacity, it also comes with a hydraulic mechanism, making it a manual hydraulic press.  And it has a pressure gauge!

The basket itself is so large that it can be taken apart into two sections, which is handy for cleaning, but even handier for removing the pomace after pressing is done.

We have to move the press with the tractor though, it is much too heavy for any of us.

Crushed and destemmed grapes are
dumped into the basket

Grapes are pressed and juice runs out

When the pressing is done, the basket pieces can be removed and the pomace is exposed, which can then easily be removed with a pitch fork and carted to the compost pile.

Experimenting with Acid Adjustment in Wine

We tested our 2013 Chambourcin and found that the pH level was a bit on the high side - high enough to consider adjusting the acid content just a bit to ensure the wine is balanced and remains stable once we bottle it.

We tried different amounts of acid, as well as different types of acid, including tartaric, citric and a commercially available "acid blend".   Jars with different tasting wine have been sitting around our kitchen all weekend, and we kept taste-testing and measuring the pH levels.  Nothing much changed in the readings after the first couple of hours.

No matter how often we taste-tested,  our  preference was always for the wine with the added tartaric acid  (which is one of the main acids in wine anyhow).  So that will be the added acid of choice.

We are hoping that this will give out wine more balance, without adding any sharpness.  Tina had some of the tartaric acid jar-wine with dinner and it was rather good!

More Wine Chemistry

Another three day Wine Chemistry & Microbiology lab weekend just ended.  We had even more "hands-on" experiment time, using and comparing different methods to analyze various wine components.  From conductivity tests to check for cold stabilization, to ripper titrations for measuring levels of SO2, we were busy the entire time.

This morning we worked with microscopes and learned how to identify different strains of yeasts as well as spoilage organisms.  So now we have another item for our winery wish list:  a decent microscope (which would be right after the ebulliometer)!

By the way,  our chromatograms for checking on malolactic fermentation progress turned out a lot better than during our first attempts: