According to Chef Vu Nhat Thong from Eric Vu cooking class, there are two main reasons fish sticks to the pan.

First, moist fish skin. According to the Maillard reaction, when a wet surface touches a hot pan, water must evaporate first, holding the temperature at 100 degrees C. This process hinders the formation of a crispy crust, causing protein on the fish skin to adhere firmly to the pan's metal surface.

Second, uneven protein contraction. Fish skin contains much collagen, and when exposed suddenly to high temperatures, it contracts, causing the fish piece to warp. The part of the skin touching the pan sticks firmly, while the raised portion does not receive even heat.

For crispy fish that doesn't stick, the skin needs to be blotted dry before frying. Photo: Bui Thuy

To prevent fish from sticking, home cooks should follow four steps:

1. Dry the surface: Use kitchen paper towels to blot the fish skin completely dry. Cooks can also leave the fish (uncovered) in the refrigerator for about 30 minutes to allow the cold air to air-dry the surface. Dry fish skin helps the Maillard reaction occur quickly, creating a crispy crust that automatically separates from the pan.

2. Control heat: Prioritize using cast iron or steel pans. Heat the pan and oil until the oil surface shimmers, avoiding smoke. Test the temperature by dropping a single drop of water: if it sizzles and evaporates immediately, the temperature is optimal.

3. Secure the surface: When placing the fish skin-side down in the pan, the skin will contract, and the middle of the fish piece tends to bulge. The cook should gently press down on the entire fish piece for the first 10-15 seconds to keep it flat, ensuring the skin makes even contact with the heat.

4. Wait: This is the most important step. Absolutely do not move or flip the fish until the crust is sufficiently crisp. When the Maillard reaction is complete, proteins harden, and the skin will automatically separate from the pan surface. At this point, simply slide a spatula gently underneath and flip the fish, cooking the flesh side for 1-2 minutes, depending on its thickness.

Unlike beef, which needs to rest for 5-10 minutes after cooking for moisture to distribute evenly, fish can be enjoyed immediately. Fish muscle fibers are fine, short, and contain less water than red meat, so moisture distributes almost immediately after leaving the heat. Letting fish rest only makes the dish cool quickly and lose its crispness. The only exception is large, whole grilled fish, where the core needs a few extra minutes for heat to distribute evenly after being removed from the oven.

Bao Nhien