Dried Mulberry Preparation:
Harvesting
The fruit is shaken from the trees directly onto large sheet. It is then emptied from the sheet into fruit crates. The branches are tapped by a 2 kg mallet, causing a mixture of ripe and partly dried mulberries to fall onto the sheet, held by the four corners underneath. As fruit is tipped from the sheet into the crates, leaves, branches and insects can be removed. The mallet must be strapped to the person using it, to avoid the risk to anyone standing underneath.
Treatment
A 10 litre sulphuring solution is prepared in a plastic tub. The solution is prepared by adding 50g of sodium metabisulphite and 20g of citric acid to 10L of clean water. A plastic mesh is placed into the tub of solution. 3.5Kg of ripe mulberries at a time are then poured onto the mesh, which sinks to immerse the fruit in the water. For a maximum period of 5 minutes, the fruit is gently moved by hand, and any leaf and twig fragments, or diseased fruit are removed. After 5 minutes, the four corners of the mesh are gathered together to lift the washed fruit out of the solution. The fruit is drained by gently shaking the mesh, and then transferred to 10 litres of clean water for a brief rinse to remove any sulphur solution. The fruit is again drained, and transferred to a drying tray in the fruit drier. The fruit is spread in a thin layer on the drying tray. A total of 7kg of washed fruit is placed on each tray. After 10.5kg of fruit have been washed, the sulphuring solution becomes dirty and weakened, and so is changed.
Destalking and grading. After 3 days in the drier, the fruit is gathered into a pile in the centre of the tray using a flat plastic scraper to separate it from the mesh. The dried fruit is repeatedly churned by hand. This causes the stalks to fall off, and they then pass through the bottom of the tray. The dried fruit is then sieved over a mesh of dimensions 4mm to remove broken or damaged fruit. The sieved fruit is loaded directly into a storage crate.
Equilibration
This is the name used to describe the process for the moisture becoming equal in all parts of the fruit. Up to 10kg of sorted fruit are placed in cartons. Care being taken to ensure that no moths or insects enter the dryer or carton. The cartons are then carefully netted, and set in a well ventilated cool room, on a raised surface, for 5 days of equilibration. During the drying process, the outside of the mulberry becomes hard, preventing moisture from leaving the centre of the fruit. After 5 days, if the fruit is sticking together, it should be returned to the drier for 12 hours to remove excess moisture. Mulberries are best stored and sold in paper bags. This allows the fruit to breath.