As far as price is concerned, the price of Dongyan is higher than that of domestic swallow.
Because the cave swallow is built in the cliff cave, the picking risk coefficient is large and the cost is high. In addition, people who collect cave swallows covet the huge benefits of cave swallows, and do not consider the law of ecological balance when collecting them, which makes it difficult for canaries living in caves to breed and leads to the scarcity of cave swallows, so the price of cave swallows is higher than that of eaves.
Yes, bird's nest is really rare. Is the expensive cave swallow really better than the domestic swallow? Is the value of cave swallow higher than that of eaves?
Due to the scarcity and high price of Dongyan, many merchants boast that Dongyan is wild and has not been raised, and their nests are built on rock walls, so the mineral content in bird's nest is high and the nutritional value is richer. But is this statement really reliable? Although the bird's nest is built on the rock wall, the minerals in the rock wall slowly penetrate into the bird's nest, but nothing is absolute. The rock is likely to contain heavy metals, and substances harmful to the human body will also penetrate into the bird's nest.
There is not much human intervention on the roof except to provide a swallow house artificially. Jin Siyan foraged alone in the wild, which is no different from Dongyan. Moreover, because the nest is built in an artificial bird's nest, it will not be disturbed by uncertain minerals and there will be no potential harm from heavy metal minerals.
As far as nutritional value is concerned, the domestic swallow and Dong Yan Dou are wild, but the domestic swallow is wild. Jin Siyan nests in the house, so there is not much difference in general nutritional value. Even if the environment of cave swallows is not artificially protected and not picked or eroded by pests, their nutritional value will be greatly reduced.
Domestic swallow is cleaner and simpler than cave swallow. Because the environment in the cave is not clean, there are all kinds of excrement in the cave and it is full of all kinds of stench. Dongyan has been affected by these smells for a long time, and the taste of bird's nest is getting worse and worse. On the one hand, bird's nest is also more susceptible to virus and bacteria pollution. Yanwu will be cleaned regularly, and the cleanliness will be kept very good, so the taste in Yanwu will be better and the taste will be much smaller.
To sum up, Dongyan has higher mineral content than domestic swallow, but it still has advantages in price and safety.