destem

Destem is a verb meaning to remove the stems from plant material, especially grapes, as part of processing. In wine and fruit processing, destemming separates the edible fruit from woody stems, which can contribute bitterness, green flavors, or tannins if left with the fruit. The noun destemming refers to the process or practice.

In winemaking, destemming typically occurs after harvest and before crushing. A destemmer is a mechanical device that loosens berries and separates them from stems. Most models use a drum or cage with rollers; berries fall into a receiver while stems are expelled as waste. Some systems combine destemming with crushing (destemmer-crushers) to rupture the fruit after detachment. Producers may adjust destemming intensity, choosing full or partial destemming to control tannin extraction and herbaceous components.

Destemming is also used in other fruit processing, including olives and various berries, where removing stems can improve texture, flavor, and processing efficiency. In olive processing, destemming helps remove stems and related material before pressing in some mills. In berries, destemming can reduce spoilage and improve consistency during fermentation or storage.

The term applies to many fruits beyond grapes; destemmed fruit is often preferred for fermentation, freezing, or packaging. The practice can influence yield, flavor development, and processing behavior, and may be tailored to the desired style or product specifications.