Bird's nest

As with several other Chinese delicacies, such as shark's fin and sea cucumber, bird's nest is appreciated primarily for its texture and ability to absorb other flavours rather than for its inherent taste, which is minimal. What are they? Small nests made by certain breeds of tiny swiftlets. Unlike conventional nests, made from twigs, feathers, grass and other objects, the edible varieties are made mostly from the bird's sticky saliva. Traditionally, the birds built their nests on the high walls of caves, making their harvest a dangerous enterprise. Now, the birds are encouraged to breed in empty buildings, making nest collection much easier.
Where are they from? The main sources are Indonesia, Thailand and Vietnam.

What to look for: it's best to buy from a reputable dealer, because fakes are common. The best, most expensive nests are cleaned of most of the feathers, twigs and other debris. Those tinged with red - which is blood emitted by the bird as it builds the nest - are extremely valuable. Whole nests cost more than broken ones and fragments.

How is it available? Nests are sold by specialist dealers. Prepared bird's nest - made into soups and drinks - is sold in some supermarkets.

What else? It's believed to be good for the complexion, general health and virility. Because it's considered so nutritious, it's often prescribed to invalids and the elderly.

Bird's nest is - or should be - a sustainable resource. In the past, harvesters waited for the baby birds to grow up and fly away before they took a nest. These days the nests are so valuable some harvesters take them with the eggs still in them, a practice that has depleted bird numbers. There are reports of armed gangs monopolising the harvest.

How to prepare: the nest should be soaked in water to soften it so any feathers and debris can be removed. For sweet soups, the cleaned nests are cooked with rock sugar and other ingredients such as ginseng, coconut milk and lotus seeds.

Savoury bird's nest soup is made by simmering the prepared nests in good-quality stock made with chicken and dried ham. Before serving, other ingredients such as crab meat, sherry (or whisky) and fresh coriander are stirred into the pot.