Destemmers & Crushers

Grape Destemmers and Crushers for Winemaking

Destemming and Crushing are often viewed as a single step within the winemaking process, as they are typically done at the same stage, using the same machine.
Destemming removes stems, leaves, jacks, etc. that contain harsh, astringent tannins and vegetal compounds, reducing bitter/green notes, and producing smoother, more approachable wines. Crushing breaks berry skins enabling color, tannin, and aroma extraction during maceration, and allows the sugar and nutrients in the juice to access the yeast, facilitating fermentation.
There are three primary types of machines that perform destemming and crushing:

Destemming and Crushing

Crusher Destemmers
 Grape clusters are gravity-fed through a pair of counter-rotating grooved rollers that compress and split the skins as they pass through. From there, the crushed grape clusters fall onto a concave destemming grate that runs the length of the machine. A rotating shaft with angled paddles moves the material along the grate, separating the stems from the fruit, allowing the fruit to fall through the holes in the grate while the stems exit out the end of the Crusher Destemmer. The machine is usually mounted on a stand with a chute that can be placed over a bucket to collect the must (destemmed and crushed grapes).
Compact and economical, powered by a small electric motor or manual operation, and typically have a maximum production around 1.0 ton per hour, Crusher Destemmers are easy to use and have very low maintenance.
Crushing before destemming results in the extraction of astringent and harsh tannins from undesired materials (stems, leaves, jacks, twigs, etc.). Crushed stems and debris are more likely to fall through the grate with the fruit.

 Destemmers with Must Pumps
 Rather than having a dedicated crusher, whole grape clusters move directly from the loading hopper to a destemming grate that runs the length of the machine. The destemming shaft separates the stems from the fruit, allowing the whole grapes to drop through the holes in the grate while the stems are carried out though a chute at the end of the machine. A second auger feeds the destemmed grapes into the on-board must pump, where the centrifugal force of the stainless-steel impellers breaks the skin of the grapes, compressing the grapes and breaking the skins enough to extract free-run juice.
Destemming before crushing results in cleaner must with less debris and astringent tannins. Gentle crushing of the pump leaves grape seeds intact. Larger units have full destemming drum and two-speed operation. Single motor makes for easy operation.
The must pump cannot be bypassed. The type of pump and the speed / power of it cannot be changed the adjust the level of crushing performed.

 Destemmer Crushers
 Destemmer Crushers feature a full destemming drum that rotates the opposite direction of the destemming shaft to mitigate the risk of loose stems falling through the holes with the fruit. The destemming shaft features soft, silicone paddles that are adjustable in depth and angle to maximize stem removal while minimizing the risk of damage to the grapes. Independent variable speed motors control drum, infeed auger, and destemming shaft rotation to allow for fine tuning of each step in the process. Crushing units, which can be bypassed altogether, use large soft rollers that are adjustable in depth to control the amount of skin breakage. Destemmer Crushers are typically either elevated so as to fit a macro beneath it, or include a motorized must collection hopper so grapes and/or must can be transferred directly to a fermenter or press.