CLASSIFICATION OF SWALLOW NEST

Swallow nest is classified into cave nest and house nest in terms of sourcing.

Cave nests are those constructed by edible-nest swiftlets in caves and on cliffs. Owing to the harsh natural climate and environment, the nest is firm, hard and deep in color. It is not as well shaped as house nest and exhibits higher impurities. Cave nest is crunchy with a low swelling capacity that lengthens the time for it to swell when preparing.

House nest refers to the nest built in wooden-roofed swallow farmhouses that are humid and dark. The interior temperature is kept at around 30 ¢J. Brightness and humidity (about 90%) are also maintained to the conditions similar to the bird's natural cave habitat. Swiftlets leave the farmhouse to find food in the wild in the morning and returns in the evening.
Since the farmhouse provides the swallows a better habitat, house nests are much cleaner with less impurities and feathers. They also have an intact cup shape, and have a high swelling capacity.

Swallow nest is also classified according to colors: white, blood-red and yellow, even grey and purple. Different colors exist in the nests because swiftlets feed on different food. White nests are generally smooth, while yellow and blood-red nests are crunchier because they contain more minerals than white nests.
The market generally differentiates swallow nest based on its appearance: the natural whole nest cup, nest strips, nest pieces, and the irregular shaped nest cake processed from nest pieces. The whole nest cup looks better, has the highest nutritional value and is priced the highest. Most nest cups come from house nests.

During processing and shipping, some nest cups are broken into strips and pieces and they are then sold as such. Their swelling capacity and prices are lower but the nutritional value is the same as that of nest cups. However, because cave nests contain more impurities and feathers, the nests may be required to be broken during processing in order to remove dirt and feathers. After disintegration and removal of feathers and impurities, the nest may be sold in nest strips and nest pieces, or molded into the shape of a nest cake. These nests generally contain less nest-cement and are of less nutritional value.