Canning process of raspberries

Raspberries are an important commercial fruit crop, widely grown in all temperate regions of the world. The raspberry is the edible fruit of a multitude of plant species in the genus Rubus. Red and black raspberries are canned by the same methods.

Raspberries should be picked when they are ripe but firm. The raspberries are then conveyed to the factory in crates of the shallow boxes to prevent bruising or crushing of the fruit.

Raspberries, like most berries, require considerable hand labor in preparing for canning. Berries are washed and sorted to remove the deformed and overripe berries unfit for canning. Raspberries are size graded using slat riddled.

The berries are placed in cans as they are washed, the filled can inverted to drain off the excess water, and the cans generally placed on a belt or some other type of filled can conveyor to carry them to the syruper.

The berries are canned in heavy syrup (50°-55° Brix) for dessert purpose, or in water for use in pies. If syrup is used, it should be added at a temperatue of at least 93 ° C. Some canners believe that the use of syrup that is too hot causes shrinkage of the berries.

Cans are exhausted until a center temperature of 18 °C is reached. This requires approximately 5-6 min at 100 °C.
Canning process of raspberries

Raspberries fruit processing

Berries designed for processing are picked at a full to dark red stage, when fruit adhesion is minimal and machines can easily dislodge berries by using a shaking system. Fresh berries are transported directly from the grower or packer to the processor. Berries are washed and sorted to remove the deformed and overripe berries unfit for canning.

The berries should be shaken gently onto a wide white inspection belt, where inspectors will remove any foreign bodies such as calices, insects, leaf, twig and stones.

The berries should be clean and fee of rot or significant mold and posses typical color and flavor.

Raspberries are size graded using slat riddles. The berries are canned in heavy syrup (50-55 °Brix) foe dessert purpose or in water for use in pies.

Cans are exhausted until a center temperature of 18 ° C is reached.

For processing of puree, after washing the berries are either frozen in drums or totes for further processing or conveyed to a chopper or disintegrator.

After chopping, the berry is sieved or screened in a pulper/finisher to remove extraneours material (leaves, cap) and a homogenous puree is produced.

For seedless raspberry puree is produced using a screen of .045 in and screens of .060 or .125 in would be used for a raspberry puree with seeds.
Raspberries fruit processing