Fish drying is the traditional, cheapest and oldest method of preservation. Drying preserve the fish by reducing the water available for microbial growth and increase shelf life and thus prevent wastage of fish. Drying reduces the weight and volume, minimizing packing, storage, and transportation costs and enables storability of the product under ambient temperatures. Sun drying of fish is a simple and the oldest known method of fish preservation and is considered as the least expensive method of fish 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.
* Wash and clean the fresh fish landed immediately in clean water or clean sea water to remove slime, adhering dirt etc.
* Remove the gills and viscera ( especially big fishes); clean and wash the fish.
* Make a lateral cut along the center of the back bone and split open the fish.
* Apply salt to fish in 3:1 to 6:1 ratio (fish to salt). The amount of salt may vary depending on the size of the fish.
* Keep salted fish for 1-2 days to absorb the salt properly.
* Wash clearly the salted fish in saturated salt solution.
* Immerse the salted fish in saturated salt solution containing 5% calcium propionate and 10 ppm chlorine for 2-5 minutes.
* Take the fish out and allow the water to drain off.
* Open/sun dry the fish in clean and raised platforms/stacks/high racks till the moisture content reaches 25% or below. Otherwise mechanical drier can also use.
* The fishes dried in this way will have shelf life of 6 months.
* Pack the dried fish in good quality laminated pouches.
Preparation of Saturated Salt solution to Immerse the Fish
| 10 PPM Chlorinated Saturated salt Solution | 1 L |
| Calcium propionate | 50 GM |
Note1
Small fishes (anchovy) can be dried without salting.
Note 2
Preparation of 10 PPM Chlorinated Saturated salt Solution
Add 350 gm salt to 1 litre 10 PPM chlorinated solution at room temperature and mix well to get required solution.
Note 3
Preparation of 10 PPM Chlorinated Solution
Add 116 µl (micro litre) of 8.58% Sodium Hypochlorite solution to 1 litre water to get 10 PPM chlorinated (1 lire) solution. This can be upscaled based on the requirements.