|technology > size reduction, mixing, forming > cutting, slicing, chopping|
Cutting, slicing, chopping, mincing, pulping, pressing
|Field of application|
|Techniques, methods and equipment|
cheese, vegetables, fruits, potatoes, and various crops (sugar beet).
size reduction of large to medium sized parts of food material; knives, blades, cleavers or saws are usually used for the cutting. Cutting is an important operation in meat and fish processing. Cutting of meat is used post slaughtering to dress and split carcases, to remove offal and to remove appendages and, where required, excess fat and bones. Carcases are further reduced into retail cuts of joints by the removal of bone, skin and fat. Meat prepared for further processing into ham, bacon, sausage, etc., will be treated initially in a similar manner to fresh meat, and will then be subject to further processing operations. These may include further deboning, derinding, defatting, slicing, comminuting, emulsifying, etc. The cutting equipment used in meat processing includes power operated cleavers, circular or straight saws for splitting carcases, and band saws for the further reduction of the carcases. These are all electrically operated. Special derinding machines are used for separating rind and fat from pork carcases. The cutting of potatoes for the production of french-fries often involves the use of hydro cutters (where the potatoes are conveyed by water at high speed over fixed blades).
sugar industry sugar beets are cut into thin slices, called “cossettes”. A variant of slicing is dicing (applied to vegetables, fruits and meats), where the food is first sliced and then cut into strips by rotating blades. The strips are passed on to a second set of rotating knives, which operate at right angles to the first set, and cut the strips into cubes.
extrusion (where the meat is passed through a plate with orifices).
fruit and vegetables. A moving rough surface ruptures the fruits (vegetables) and squeezes the material through a gap producing an homogenised mass. The most common pulpers are drum pulpers and disc pulpers. Sometimes the pulping process is used for juice extraction.
wine production but also for some other alcoholic beverages.
Different types of presses are used. The main ones are:
Horizontal pneumatic presses
A pneumatic membrane located in the centre of the press is inflated: berries are slowly pressed liberating the must in a tank when the solid parts remain in the press.
Hydraulic compression vertical presses
Grapes are placed in a “cage” which maintains the grapes during the pressing. A horizontal tray presses the grapes vertically. The must flows through the cage and is collected in a tank for further processing. The grapes remain in the cage.
There are also other types of presses: e.g. belt presses, horizontal presses, etc.