Seafood is a delicate thing, and to preserve its freshness and high quality while frozen, a protective layer of water is added to the surface of frozen seafood. This ice layer is called "glaze". Frozen seafood is often glazed with a protective layer of drinking water, in order to preserve quality during transport and storage.

Glaze is a protective layer of water added to the surface of frozen seafood. if the coating thickness was too low (<6%), it might not be able to play a protective function completely over storage time, but excessive glazing (>12%) may harm the interests of customers. The optimum level of glaze is around 10% of the weight, although there is no legal maximum for the amount of glaze that can be used. The deglazed weight or ‘net weight’ is the true amount of product once the glaze is removed. When all similar products only show the net weight it allows the consumer to easily compare products before purchasing. This 'glaze' is considered to be part of the packaging material, and therefore must be excluded from the net contents.

Glaze is an effective packaging aid for fish and seafood, to preserve the quality of the product. Packaging in a protective layer of ice minimises the risk of contact with the air and extends the durability of the product. When the rate of oxidation is reduced, rancidity is minimised. Glaze protects against minor temperature fluctuations and freezer burn during transport and storage.

Quality assurance of the glaze is in accordance with the guidelines created by Codex Alimentarius, which is an independent organisation under FAO/WHO with the purpose of creating global standards for food and food production. For instance, the Codex standard for frozen prawns consists of a sensory and a physical examination, defrosting and weighing, based on a carefully defined procedure with required temperature conditions and applied equipment, as well as different types of cooking, whereby the quality of the product is evaluated. Royal Greenland uses this method for its quality controls.