Having eaten tiny fish, insects and Marine algae, swiftlets spit out their saliva to make nests which become edible after they have been cleaned and processed manually.
燕窝为金丝燕吞食海中小鱼或其他蚕螺海藻等小生物后，用吐出的唾液凝结而成的燕窝巢。
2
As for the investigation of fraudulent trade practices, precious commodities such as shark's fin and swiftlets nests are regularly submitted for certification of their authenticity.