1. Randomly select the products from cold store, open immediately ，weigh the samplesand place the products into a plastic mesh basket .

2. Defreeze the products with flow water (with temperature around 10-15°C)

3. Remove the products from water until the ice glaze that can be seen or felt is removed and the products became soft. During defrosting, it is not allowed to use hands to press the products.

4. Incline the plastic mesh basket at an angle of about 20° to drain the products, until the water not drip in line（around 3 mins） then weigh the products.

5. Net weight=(weight after defrosting/weight before defrosting)*100

6. Weigh piece by piece of defrosting fish to get size