Wine Arcana

Concept

Blending

Blending combines grapes, musts, or wines to make a chosen final wine. The components may differ in variety, vineyard, harvest date, vintage, extraction, or maturation vessel. Even a wine labeled with one grape and one year can be assembled from several separately fermented lots.

The purpose may be to combine complementary properties, maintain a recognizable house style, express a larger geographical origin, or select the lots that belong in a particular bottling.

What is combined, and when

A field blend begins with varieties planted together, often picked and fermented together. Cofermentation also brings components together before their separate wines exist: a producer may put grapes from different varieties into the same fermenter. The subsequent extraction and fermentation occur in a shared environment.

Separately fermented lots leave another set of options open. A winemaker can compare individual parcels, free-run wine and press wine, or barrels with different histories before selecting proportions. Keeping the lots apart preserves flexibility, but requires cellar space, tracking, and repeated tasting.

A varietal wine can involve extensive blending within its named grape. The label's wording is governed by origin and labeling rules; it does not disclose every cellar lot used to make the wine.

Regional examples

Bordeaux illustrates blending between grapes with different ripening behaviour and structural contributions. Merlot, Cabernet Sauvignon, and Cabernet Franc can all contribute, with proportions changing by site, estate, and vintage. The winemaker selects proportions after assessing the components from that season.

Champagne extends the decision across vineyards, grapes, and harvest years. Reserve wines give a producer material already developed in the cellar to combine with younger wine. A vintage Champagne still involves selection and can combine several parcels or varieties.1. Comité Champagne, “Blending,” description of grape, vineyard, vintage, and reserve-wine choices.

Testing a possible blend

Bench trials compare small, measured mixtures before a cellar-scale decision. The unblended components and several candidate proportions provide useful reference points. Recording the volumes makes a preferred mixture reproducible; tasting without seeing the recipe can reduce expectations about which component ought to dominate.

Composition and perception require different kinds of checking. Alcohol or sugar can be estimated by weighted quantities when measurements and units are consistent. pH is affected by buffering and should be measured in the mixture. Aroma, bitterness, and astringency also interact, so tasting one component alone cannot establish its effect at a small proportion in another wine.

Stability and the final wine

Combining two clear wines does not establish that the mixture will remain stable. The final blend still needs appropriate analytical, microbial, and stability checks before bottling. Fining, filtration, and tartrate stabilization address different problems and are considered for the finished composition.

Sources