Prawn is an important source of high quality protein and is an extremely perishable commodity and quality loss can occur rapidly after catch. Drying preserve the food by reducing the water available for microbial growth and increase shelf life and thus prevent wastage of food. Drying reduces the weight and volume, minimizing packing, storage, and transportation costs and enables storability of the product under ambient temperatures. Sun drying of prawn is a simple and the oldest known method of prawn preservation and is considered as the least expensive method of prawn preservation. Sun drying depends on the weather conditions and it requires a large open space area exposed to direct sunlight and it is generally inefficient. In the modern industrial drying, the use of mechanical dryers provide less drying time, high efficiency and higher drying rates.
* Generally prawns can be dried in two methods.
Total Drying
* Wash and clean the fresh prawn in potable water.
* Drain off the water.
* Weigh the prawn and dip in boiling 10% brine solution containing 0.2% citric acid for 30 seconds.
* Take the prawn out and drain off the water.
* open/sun dry the prawn in clean and raised platforms/ high racks.otherwise mechanical drier can also use.
* The prawns dried in this way will have shelf life of 6 months.
* Pack the dried prawn in good quality laminated pouches.
Prawn Pulp Drying
* Wash and clean the fresh prawn in potable water.
* Drain off the water.
* Weigh the prawn and put in boiling 3.5% brine solution containing 0.2% citric acid for 20 minutes.
* Take the prawn out and drain off the water.
* Open/sun dry the prawn in clean and raised platforms/high racks. Otherwise mechanical drier can also use.
* De-shell the prawn either manually or mechanically.
* Pack the dried prawn pulp in good quality laminated pouches.
Preparation of Brine Solution .
* Ingredients serially numbered from 2 to 4 are required for Brine Solution
* Take 1.2 litre of potable water; add 35 gm (3.5%) salt and 1.2 gm (0.2%) citric acid to the water. Mix the solution properly to get brine solution.