Post harvest Management of Horticultural Crops (2+1)

Washing

Washing


• Washing of fruits and vegetables is done to remove adhering dirt, stains, insects, molds and sometimes spray residues.
• Washing not only help in cleaning and making the vegetables/fruits fresh and also improves appearance, it also helps in extending the shelf life of the produce.
• Washing is done manually under tap water or in a wash tank using soft muslin cloth.
• Produce should be thoroughly washed with clean water (preferably with 100 – 150 ppm hypochlorite/chlorine) or soap or calcium hydroxide. Most efficient detergent used is sodium meta bisulphate.

• After washing they are then wiped with dry muslin cloth or air-dried to remove excess surface moisture. Under automated systems, the produce passes under a spray washer on a moving conveyor rollers.

• Thumb rule is to use 1 to 2 ml of chlorine bleach per liter of water gives 100-150 ppm of Cl. pH of the water must be around 6.5 to 7.5.
• Sanitation is essential, both to control the spread of disease from one item to another, and to limit spore buildup in wash water or in the packinghouse air. Fungicide may be used as post harvest dip to control diseases and disorder.

• Excess water should be removed from the produce to avoid rotting.
• In crops where water dipping is possible, differential floatation could be used to separate rejects.
• Root and tuber vegetables are often washed to remove adhering soil.




The choice of brushing and/or washing will depends on the type of commodity and contamination.