Maturing of the wine
As its name indicates, "maturing" is a period of both formation and correction and also the refining of the young wine. It goes into the barrel where through the pores of the wood, controlled oxidation forges the personality of the future wine.
Together with other biochemical compounds and mechanisms, esters and aldehydes are the result of this oxidation, and form substances which give a wine its perfume and flavour, intensified and rounded through maturity and ageing.
In winemaking terms, "maturing" is the time the wine stays in the barrel and "ageing" is a further period of development in the bottle. These processes complement each other, and produce a more stable wine with refined aroma, elegant colour, and delicate flavour.
The result will depend on the type of oak used, the age of the barrel, the number of rackings that take place.
In López de Heredia, maturing takes place in barrels made of oak from the United States, as has been said. New barrels form l0%; middle-aged barrels (l0 years old) form 50%; and the rest are made of wood more than l0 years old.
The ageing of our barrels is understandable, justified, if we look at our method of natural stabilisation for wines. It is certain that the transfer of flavour and aroma from the oak to the wine as well as porosity reduces with age, so it would be unproductive to use old barrels, if the intention is to maximise the contribution made by the wood in the shortest space of time.
For this reason, in our bodega, wine is not filtered. Stabilisation results with the passage of time, in peace and quiet, with continual racking and without accelerating the natural developmental process of the wine. It therefore involves having barrels of different ages, making the oldest into recipients in which wines stabilise patiently, providing moderate oxidation and the disappearance of a woody flavour and aroma.
We can say, finally, that controlling the development process in all its aspects allows us the option of choosing the most suitable alternative at any point, thus guaranteeing the perfect development of our wines throughout the long and crucial period of ageing.
A master cooper banding the barrel
Fermentation in oak or in stainless steel?
The range of containers in which wine can be fermented is very broad; each of them has its own advantages and disadvantages. None of them is perfect, and once more the winemaker is responsible for ensuring the best performance from each.
In López de Heredia we ferment all the grapes from our own vines, in oak casks more than 132 years old, kept and maintained in perfect condition by our coopers.
It is particularly important to point out that the roughened walls of the cask accumulate deposits of tartrates and other compounds over the years, forming a protective layer that is a perfect habitat for the yeasts which lie dormant, as hardy spores, from year to year. It is the action of these yeasts that drives fermentation.
This enables us to retain our own microbial flora, without having to use industrial yeasts, a process which would cause the loss of the original character and personality that home-grown yeasts contribute to our wines.