15 meters underground, in the troglodytic cellars of the winery Domaine de Rocheville, let yourself be surprised by an unusual wine-aging container.
More modern than an amphora, more original than an barrel, more aesthetic than a stainless steel tank, its familiar shape nevertheless arouses the curiosity of visitors because it is… an egg! A stoneware egg filled with Saumur Champigny red wine !
What is wine aging?
Wine aging is a crucial stage in the winemaking process that takes place after fermentation. The aim of aging is to give the wine a certain complexity and character by letting it rest for a certain period in a specific container before bottling.
How does wine aging work?
During this period, the wine will evolve thanks to different physical and chemical processes such as oxygenation, evaporation and interaction with the elements of the container. aging also allows the wine to stabilize and develop more complex aromas and flavors.
aging can last from a few months to a few years depending on the terroir, the colour of the wine, the grape variety(ies) used and the type of wine the winemaker wishes to produce.
In which containers can wine be aged?
In this area, winemakers compete with each other in imagination. Of course, the traditional barrel and stainless steel vat are well known for aging both red and white wine, but there are also other more unusual containers such as terracotta jars, amphorae and concrete or ceramic eggs.
Each method marks the wine in a specific way.
Wine aging in oak barrels
In French, different words are used to describe the different casks used to age wine, depending on their capacity : from the “quartaut” (56 litres) to the “demi-muid” (500 to 600 litres) and the “Bordeaux barrel” (225 litres).
Used for centuries to transport wine by boat, the barrel has gradually been used for aging because of its influence on the quality and aromas of the wine. Indeed, it gives the precious liquid notes of vanilla, coconut, toast, smoke, etc.
Moreover, unlike stainless steel tanks, which are perfectly sealed, wood is a porous material that allows micro-oxygenation, i.e. slow and controlled exposure of the wine to oxygen, which helps stabilise its colour and tannic structure.
Finally, barrel aging can also slow down the maturation of the wine and lead it to develop greater aromatic and taste complexity.
As a result, barrels produce wines with good balance, more tannin and generally longer aging potential, such as our Saumur-Champigny Le Fou du Roi 2014, which has an aging potential of 10 to 15 years.
Did you know that French oak trees used in cooperage are on average 200 years old?
What patience it takes to get from tree to barrel!
Wine aging in casks
A wine estate can also choose to age its wine in larger barrels, called foudres, which generally vary in size from 1000 to 10000 litres. Domaine de Rocheville has 4 oak foudres from the Tronçais forest (Allier), each with a capacity of 30 hl.
The large size of a barrel reduces the contact between the wine and the wood, giving the wine more discreet and well-balanced tannins. In addition, it allows slow and controlled oxygenation of the wine during maturation, which favours the evolution of aromas and flavours.
Thanks to its large storage capacity, it ensures a better thermal stability of the wine and consequently a more regular fermentation and a better conservation.
Tuns are often used for the maturing of top-of-the-range wines, as they bring finesse and elegance. At Rocheville, this is the case for the Cuvée Le Roi, in the Saumur Champigny appellation, which presents a fine balance between fine tannins and the expression of the clay-limestone soil.
And what a pleasure for the eye!
Wine aging in stainless steel tanks
Modern, durable and easy to maintain, stainless steel tanks have no impact on the taste or aroma of the wine. They are perfect for expressing the freshness and minerality of the terroir in combination with the fruity aromas of the grape varieties.
In addition, thermo-regulated tanks allow precise temperature control, which is particularly important during fermentation. This allows the winemaker to control the speed of fermentation and preserve the aromas and colour of the wine.
Wines matured in stainless steel tanks can also be bottled more quickly than those matured in oak barrels.
In Rocheville, it is the cuvées in which freshness and delicacy are sought, such as Le Troubadour (AOP Saumur Rosé), Le Page (AOP Saumur Champigny) or Le Prince (AOP Saumur Champigny).
Wine aging in concrete tanks
As an alternative to stainless steel tanks, concrete tanks have a porosity that favours controlled micro-oxygenation of the wine without adding woody notes.
Neutral in terms of taste and smell, concrete also preserves the natural character of the wine and highlights the terroir and the grape variety.
Another advantage is that concrete tanks are easier to clean than wooden barrels, which reduces the risk of bacterial contamination. Finally, they are also more durable and economical in the long term.
Finally, they are ideal for winemakers who produce large volumes.
In sum, the choice of the maturing container depends on the style of wine the winemaker wishes to produce and his or her preferences in terms of aromas and flavours.
More unusual containers for aging the wine
As we know, winegrowers like to experiment to improve their wine or create new vintages. They sometimes opt for original methods, such as maturing the wine in amphorae, in Qvevri (a terracotta jar used in Georgia) or even aging the wine in concrete or stoneware eggs, to give a unique touch to their cuvée.
With this in mind, Philippe Porché and Jérôme Callet (Domaine de Rocheville) decided, in December 2019, to experiment with stoneware eggs for the aging of a Saumur Champigny. Since then, comfortably installed in our troglodytic cellars, these innovative containers surprise and question the curious who venture into the galleries.
Wine aging in stoneware egg
Where do Domaine de Rocheville’s stoneware eggs come from?
Raising a Saumur Champigny in stoneware eggs is a good idea. But where to find the eggs?
The first difficulty was to find eggs made in France to remain consistent with the eco-responsible philosophy of Domaine de Rocheville.
Our eggs therefore come from a company called Biopythos located near Limoges, the only manufacturer of stoneware eggs in France.
Although their origin might make you think they are made of porcelain, this is not the case: our eggs are made of stoneware. Each egg can hold 225 liters of wine, exactly the same amount as a Bordeaux barrel.
What is stoneware? What is the difference with porcelain?
Like porcelain, stoneware is a material of the ceramic family, i.e. made of clay, which can be fired to make objects.
But whereas porcelain, a speciality of Limoges, is composed of a quarter of feldspar, a quarter of silica and half of kaolin, stoneware is composed of a quarter of feldspar, a quarter of silica, a quarter of clay and a quarter of kaolin.
Furthermore, porcelain is fired at 1290°C while stoneware can be fired at 1250°C, 1260°C or 1280°C. The firing temperature is important because it determines the porosity of the egg and therefore the oxygenation of the wine.
How is a stoneware egg made?
The egg is obtained by pouring a mixture of earth and water, the barbotine, into an ovoid mould. But this form is complicated to work with because the soft paste tends to collapse.
This is why, if you have the opportunity to visit the troglodytic cellars of Domaine de Rocheville, you will notice that our eggs are not twins!
The first two, bought in 2019, have discrete bulges, like little seams, because the mould was then made up of many small layers.
The six new ones, which arrived in 2023, are more regular because the moulds have been improved in the meantime. Apart from their size, which is more reminiscent of an ostrich than a canary, they really do resemble, in shape and colour, very large hen’s eggs!
According to Fannie Reyt, sales representative at Biopythos, about a hundred French wineries use the egg shape for their wines, all materials and all wine regions combined.
The advantages of aging wine in stoneware eggs
Stoneware eggs have several advantages, the main one being their shape. The ovoid shape causes a vortex to form and this internal current encourages the natural micro-oxygenation of the wine.
Unlike the jar, which produces fruity, taut wines with soft tannins in the reds, the egg brings roundness and volume. Indeed, there are no edges to stop the movement of the wine.
Thanks to this movement, the lees (the yeasts) are always in suspension, ensuring better conditions for evolution and better stability over time.
The second advantage of the egg is its longevity. An oak barrel wears out in about ten years. Although their price is higher than that of a barrel, if eggs are well maintained, they will still perform well after 50 years!
The eggs are still fragile, so care must be taken to handle them without breaking them!
As far as the taste is concerned, egg aging enhances the terroir and the fruity character of the wine while softening the tannins. It brings finesse, elegance and a velvety texture, and highlights the aromas of the grape variety without the mark of the wood.
Our egg-aged wine
To fill our first two eggs, at the end of 2019, we chose a Saumur Champigny, because it is emblematic of our production, but also because red wine supports oxygenation better than white.
Installation of the eggs in the cellar
As far as their location was concerned, the troglodytic cellar was the obvious choice, as a room with good hygrometry was needed to limit the “angels’ share” (the natural evaporation of wine) which is consequent with eggs.
Fortunately, the Loire Valley and the Saumur vineyards are full of galleries dug into the tuffeau hillside, which offer the wine excellent conditions for aging. The eggs were therefore installed in the darkness of the Rocheville cellars, on a small, cosy nest of pebbles and at a constant temperature.
All the conditions were met to make a successful vintage!
An exclusive and numbered vintage
22 months later, the entire Rocheville team was eager to taste its first stoneware egg wine, a parcel-based cuvée named Les Hauts de Bourreau 2018.
Why this name? Our “en oeuf” cuvée was named after the parcel of old Cabernet Franc vines from which it is made, on the Parnay plateau. As for the vintage, 2018, it is that of our last year of conversion to organic farming.
It is a very limited edition, with only 524 numbered bottles!
Tasting of Les Hauts de Bourreau 2018
The result lived up to our expectations!
Fruity, elegant, with a surprisingly velvety texture and finely spiced notes, the Saumur Champigny Les Hauts de Bourreau has everything to please!
It is ideal with white meat in sauce, an assortment of cheeses or savoury pies such as a chanterelle and trumpet of death pie.
Gourmets will also love it with roast veal or lamb.
A new stoneware egg wine at Rocheville
Based on this successful experience, Domaine de Rocheville expanded the family and purchased six new stoneware eggs.
In April 2023, they were installed in one of the underground galleries by Jérôme Callet, the Rocheville cellar master and the production team. The transport, unpacking, the descent into the cellar by lift, the filling of the eggs and the bungs to prevent oxidation… each stage required a great deal of care.
Part of the Saumur-Champigny Le Prince cuvée has already begun its maturation in eggs, and this time it will last from 12 to 14 months. The other part of the cuvée is aged in stainless steel vats to be blended with the egg-aged wine.
We still have to be patient before we can taste this beautiful vintage!