Characterization of the Oxygen Transmission. Qvevri, Concrete, Stonewear

Today, there is a trend in enology promoting a return to the use of old natural materials for the manufacture of storage and maturation wine tanks. One of the most sought-after characteristics of these materials is their permeability to oxygen from the atmosphere to improve wines without this being a harmful process. The reference performance in wine aging is, without doubt, the oak barrel for its ability to oxidize wines in a controlled way, thus improving them. It would be possible to mature wines in containers in which the use of wood is not obligatory, as opposed to aging in oak barrels or foudres. This work presents the results of oxygen permeation analysis under test conditions typical of a tank containing wine, using materials, such as concrete and granite. The oxygen permeability of the materials tested was very diverse, typical of natural materials. The results showed that earthenware presents an excessive permeability, not only to atmospheric oxygen, but also to liquids and needs treatment before being used in liquid containers. Claystone and concrete can be impermeable to liquids, but maintain permeability to atmospheric oxygen—making them candidates for use in permeable tanks for wine maturation. Finally, granite has some very interesting characteristics, though thickness control is required when calculating the desired oxygen transmission rate. View Full-Text

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THE NATURAL CRADLE OF YOUR WINE

STONEWARE JARS FOR AGING AND WINEMAKING

With a lower porosity than terracotta, the Stonware is particulary suitable for white and delicate red wines, crystalline wine, delicacy aromas.

https://www.vinetterre.com/wine-jar-stoneware-sphero

Sphero

From 600 to 1000L

STONEWARE JARS FOR AGING AND WINEMAKING

Salt glaze stoneware

The salt glaze finishing on the outside only makes cleaning easy and does not change the porosity.

• Uprightness, minerality, freshness, purity
• Delicacy and lightness
• Respect of the varietal and quality of the fruit
• Authenticity of aromas

• Stainless steel valve
• Silicon bung with or without hole
• Stainless steel pallet

https://static.wixstatic.com/media/78d9c7_b8aae12dcb6840a7ae41ec3399b1a9b7~mv2.jpg/v1/fill/w_569,h_564,al_c,q_80,usm_1.20_1.00_0.01/amphore-sphero-GRAND-gres-vin-et-terre_j.webp

Inner lining of the terracotta jars: different choices, different objectives

“Terracotta, unlike wood does not confer aromas to wine – explains Bartoletti – It has an extraordinary capacity for thermal insulation which enables wine to be kept in optimal conditions. The inner lining of the terracotta jars can be decided according to the end results desired. The use of terracotta without any coating allows an intense oxygenation of the wine matured in the jar. With the use of an inner lining such as beeswax part of the gaseous exchange with the outside is reduced, and to further limit it to a bare minimum the inside of the jar can be coated with epoxy resin “.

In short the three choices, and the three different objectives:

1) Jar without lining

Allows maximum permeability of oxygen favouring the maturation of wine, polymerisation and the condensation of tannins and anthocyanins in red wines. Absolutely recommended for all varieties of grape whose resulting wines tend to reduce during aging and which need a good supply of oxygen in order to better express their characteristics.

2) Jar lined with beeswax

Limits the permeability of oxygen thus protecting the wine during aging and enables the jar to be buried in the ground without risk of seepage. Moreover, coating the jar with wax allows more effective cleaning after use.

3) Jar with epoxy coating

Allows the perfect hygiene of the jar before and after use. Greatly limits the passage of oxygen and allows the better management of wines which need a reduction favouring environment. Also ideal for storing wines whose maturation process is finished while they are waiting to be bottled.

The story of Eclipse

interview with the owners of Eclipse L.L.C., a winery from Tbilisi in Georgia, who became customers of Artenova in 2020

Why did you choose to use Jars made by Artenova?

“The decision to order specifically from Impruneta stems from a variety of factors, it is no secret that getting ceramic jars made domestically in Georgia would have been a lot easier both logistically and financially; yet here at Eclipse we take on a quality first approach. We believe that Georgian grape varieties as well as European grapes grown in Georgia will be able to compete with the main wine producers in Europe due to our rich history of wine making and thousands of soil types available for our usage. We use Bucher-Vaslin equipment in our processes, Limousin oak barrels for our barrel wine and Impruneta qvevri jars as a belief that quality is not to be sacrificed”.

The cone, the sphere, the ellipsoid, the tulip, the truncated pyramid – wine vats come in a bewildering array of shapes these days, but none has made as much of an impact on the 21st-century wine world as the egg.

The cone, the sphere, the ellipsoid, the tulip, the truncated pyramid – wine vats come in a bewildering array of shapes these days, but none has made as much of an impact on the 21st-century wine world as the egg. The advantages of the egg-shaped vessel are several. As carbon dioxide rises through the must during fermentation, the ovoid shape creates a convection current – like a natural pump-over – which facilitates homogeneity of the must and uniform fermentations.

If the wine remains in the egg for maturation, that current continues. Werner Michlits of Meinklang in Austria explains that as heavier molecules in the wine polymerise, they sink to the bottom of the vessel and push lighter ones upwards. This creates a continuous battonage, increasing lees contact and enhancing the wine’s texture. Benefiting from the flavour neutrality and micro-oxygenating properties of the materials they are made of (concrete, clay, high-vitrification ceramics), eggs also promote fruit purity and aromatics. https://imbibe.com/news/its-all-ova-now-the-rise-of-egg-fermenters/

While concrete is by far the most common material for egg-shaped wine vessels, it’s not the only one. In 2012 an American company, Flextank, launched the first egg-shaped vessels made from durable oxygen-permeable polyethylene. They’re relatively cheap – the Orion 20hl egg tank costs $2,525 (£2,014), compared to a Nomblot 17hl egg that costs €6,100 (£5,515). Recyclable and easy to clean, Flextanks are built to last up to 20 years – that’s more than double the life of oak barrels.

They also come in heavyweight and lightweight options, which, the manufacturer says, simulate the micro-oxygenation processes of neutral and two-year-old oak barrels, respectively. Slovakian producer Slobodne has reported early positive results from its two Flextanks, which have joined its handsome collection of qvevris and tinajas. If you’re a winery with money to burn, you can also invest in the Rolls-Royce of egg-shaped vats – the Taransaud Ovum.

Launched in 2010, this 20hl vessel is priced at €45,000 (£38,984) and has been snapped up by wineries across the world, including Domaine de Chevalier in Bordeaux, Drappier in Champagne, Biblia Chora in Northern Greece and Tony Bish Wines in Napier, New Zealand. When it comes to wine quality, however, the Taransaud Ovum may not be the last word. The best material for ovoid containers, according to Australian master craftsman Philip Sedgman, is ceramic. Sedgman is an expert in flowform structures – water-flow devices associated with biodynamics. His elegant 675l Magnum 675 ceramic egg, priced at AUD$6,750 (£3,882), was inspired by the ‘Natural Selection Theory’ group of winemakers: Tom Shobbrook, James Erskine, Sam Hughes and Anton Von Klopper.

 

What happens inside the egg?

the currently prevailing theory holds that the heat of the ferment creates a torus vortex of convection currents (similar to the form of a mushroom cloud) within the egg. This moves the fermenting must or maturing wine around without intervention. Liquid near the surface of the container cools and gently sinks, unimpeded by corners. The liquid in the middle holds its temperature, but is gently pushed upwards. It then comes closer to the container surface, begins to cool and continues the process. The lack of corners in the container mean there are no “dead areas” and so homogeneity within the wine

Concrete egg

if you love the winemaking traditions of the Caucasus, you might argue that the egg fermenter never left.

Like most questions when it comes to wine, the answer is most likely to be a matter of taste. So comparing the fermentation methods of different wineries is the best way to determine if the egg is worth the squeeze.

However, the answer to one penetrating question is clear. What came first, the barrel or the egg? Clearly the egg.

Oregon made qvevri

Andrew and Annedria Beckham are the owners of Beckham Estate Vineyards in Sherwood, Oregon, where Andrew is the winemaker. Unique to Beckham Estate Vineyards, Andrew Beckham blends his two passions, wine and art, using Amphorae. Amphorae are terra cotta vessels used as part of an ancient tradition of winemaking in terra cotta vessels, thought to originate in the Republic of Georgia. This is part two of the Beckham oral history interviews. This interview takes place at Union Wine Co. in Tualatin, Oregon where Beckham stores and makes his wine. In this interview, Beckham tells about his experiences using Amphorae. To access more material in this collection, please visit Digital Commons at http://digitalcommons.linfield.edu/ow…. https://www.youtube.com/watch?v=BB1MW2kB3a4

Concrete helps to understand terroirs

One of his first steps was to replace stainless steel and wood fermentors with large, tulip-shaped concrete vats for all three wines, which are fermented with wild yeasts.

“With two years of aging in barrel,” says Ruini, “I don’t want to add more wood. Concrete is neutral. Steel has a reducing effect on wine—it’s not the best.”

Trelab presented a poster about ongoing Qvevri research at the recent Washington Association of Wine Grape Growers annual meeting.

Trelab presented a poster about ongoing Qvevri research at the recent Washington Association of Wine Grape Growers annual meeting.

via The Qvevri Project.