Reserve wines play an integral part in the production of champagne; they guarantee a continuity in quality in the blending process of non vintage champagnes and give the producer an ingredient to play with when creating blends. The classic term is reserve wine or vin perpétuelle. Simply explained, the producer has for instance a barrel where a part of the current vintage is added to aged vintages (fractional blending). Usually when making new blends, a third of the reserve wine is taken from the barrel to add to the new blend and this third is replaced with wines from the new vintage.
This blending process has two distinct advantages: a continuity of quality meaning the producer can compensate weaker vintages by adjusting the amount of reserve wines added to the blend and secondly to blends made with younger vintages the reserve wines give body and depth and counterpoints the freshness.
It has become fashionable to replace the term vin perpétuelle with the term solera. The solera system derives from sherry making, where oxadition plays a big role and here confusion arises.
There are producers, most notably Selosse, where the solera system in the sherry sense and oxidation plays a big part in his champagnes and then there are many producers, who use the term Solera for what in fact is a vin perpétuelle.
Oxidation in wines is either something you like or dislike. The champagne critic Tyson Stelzer is no fan, he writes of Jacques Selosse „Regrettably, his approach too often pushes his wines beyond the realms of sound champagne and into the outer limits of oxidation.“ You can agree or disagree with this statement.
From my point of view oxidation adds a dimension of complexity to the champagnes and makes them an excellent partner for a variety of foods. As with the oxidative wines of the Jura, you have to think beyond the oxidation, this takes a certian amount of practice but the rewards are immense.
The greatest difficulty with oxidation in Champagnes is retaining freshness, this is where producers like Selosse or Ganevat from the Jura are masters.
Recently I tasted a Mémoire Extra Brut NV from Huré Frèrés. This is a Champagne that comes 100% from reserve solera started in 1982. Each release is titled 1982 up until the last vintage added to the solera, in my case 1982-2013. The Mémoire takes some getting used to, it is one of those champagnes best drunk over 3-4 hours. The layers of complexity derived from the solera are fascinating to taste as they unravel, the oxidative element is not extreme, yet enough to add an element which gives the champagne a sherry like undertone. Perhaps not a champagne that I would drink everyday but interesting enough to warrant following its progress.
To really understand these champagnes, they should be drunk with food. My favourite pairings are most types of white proteins, Bresse Poularde, Sweatbreads, Pike Perch or even turbot paired with a classic morel sauce (morels,-dry or fresh, sherry or Vin jaune, fond (fish or chicken respectively) and cream.)
Also cheeses like Reblochen, Vacherin Mont d'Or or aged Comté work well.