Merlot

Leave either the pre-fermented juice or post-fermentation wine in contact with the skins of the grapes.

What it does

As flavors, tannins and color derive entirely from the skins, macerating with skins allows the winemaker to pull out the desired amount of same by choosing how long and when (pre- or post-alcoholic fermentation) to do so. 

Comment

Pre-fermentation maceration is uncommon with Merlot (more common with Pinot Noir) and is primarily implemented to enhance pigmentation and fruit character. Post-fermentation maceration is more traditional with Merlot, lasting 1-3 weeks, and is important to increase color, flavor, and tannin structure. It also increases tannin polymerization, a process which increases tannin molecule size and softens the wine’s tannic structure. 

What it does

Proponents of wild yeast embrace the unique flavors coming from the “place,” including savory and matchstick-like aromas that many love and associate with minimal intervention. Cultivated yeasts are more predictable and can be selected/customized to contribute specific flavors and aromas.

Comment

Some winemakers blend the two – sometimes starting with native yeast, reserving use of commercial yeast only if something does not go right (e.g. fixing a stuck fermentation). Others may create cuvées/cocktails of specific commercial yeasts to achieve a desired flavor profile, since each strain contributes something different.

The wood employed for most wine barrels, used for aging the wine or actual fermentation of the wine in the barrel. Barrel decisions include the type of wood, the amount of toast (when the staves of the barrels are bent over an open flame), size (smaller = higher ratio of wood to wine = stronger oak influence) and the age of the barrels. 

What it does:

• Chocolate, mocha, and vanilla flavors that many identify with Merlot come not from the grape but from oak-aging.
• Heavily toasted barrels impart more intense roasted flavors (caramel, molasses, toffee, coffee and burnt sugar).
• Oak bestows a waxy, velvety texture and can add a perceived sweetness to the wine. 
• New oak contributes much more flavor than older, previously used oak which, depending on the wine and the grapes, may be a better choice. 
• Small (barrique-sized) barrel fermentation at warmer temperatures than those in stainless steel and over shorter increments of time, also imparts a richer and smoother texture to the wine.

Comment

Today, there is a movement towards keeping the oak in check, i.e. minimizing “over-oaking,” or even using no oak at all. Unoaked wines (fermented in stainless steel, concrete or other neutral vessels) exist in the popular price segment, allowing the “purity” of the fruit to shine through. Unoaked and lesser-oaked Merlot is typically on the less expensive side. Use of oak alternatives would be more typical in less expensive wines. 

The vintner's practice of working with the tannin, minimizing, or maximizing its presence in the wine. Tannins can be maximized through letting the wine spend extended time on the grape skins (which also adds color) both before and after fermentation

What it does

Controls the texture and mouthfeel of the wine and mitigates bitter and astringent elements, flavor-wise and tactilely.

Comment

Tannins can be minimized by cutting back on maceration or through a very gentle filtration. To soften hard tannins, vintners are increasingly turning to a process called micro-oxygenation to soften the wine while bringing out the bright character of the fruit and adding a rich mouthfeel. With Merlot, lack of tannins can be an issue. Besides extending the macerations, blending with more tannic varieties, such as Cabernet Sauvignon, is a way to augment tannins in Merlot-based wines.

As noted above, Merlot is often made as a wine of less than 100% pure variety. Traditionally, the Bordeaux model assembles Cabernet with its familial cousins (Merlot, Cabernet Franc, Malbec and Petit Verdot) in varying percentages to make a classic ‘Bordeaux blend.” When the percentage of Merlot falls below 75%, it can no longer carry the Cabernet Sauvignon label moniker (85% for exports).

What it does

Adds additional structure to softer styles in addition to diverse flavors and an extra dimension of complexity.

Comment

Blends result in different styles of wine. Increasing the proportions of other grapes can augment Merlot’s potentially less assuming, softer character, adding nuanced flavors from the other varieties and if/as needed tannins.