Duck blood has relatively high nutritional value. The main components are water and hemoglobin, which can nourish blood and detoxify. Just add salt to fresh duck blood and let it solidify. Most duck blood on the market is made by mixing duck blood and pig blood, adding anticoagulants and food additives, and sterilizing and coagulating it.

Preparation of duck blood on the market. Duck blood is also called duck blood tofu, and the preparation method is very similar to tofu. Hemoglobin in fresh blood exists in a free form. Adding an appropriate amount of calcium salt or anticoagulant will greatly reduce the solubility of hemoglobin, resulting in smaller interactions between protein molecules and eventually coagulation. First, add anticoagulant to fresh duck blood to prevent it from coagulating. Then use a filter device to filter and sterilize the duck blood. After adding an appropriate amount of calcium salt to the clean duck blood, it will coagulate into blocks. After packaging in a suitable container and a final sterilization process, it is ready for sale. It should be noted here that the refrigerated shelf life of duck blood will not exceed three days.

The production of fake duck blood. The output of duck blood is very low, but the consumption is very high, so many companies use a mixture of pig blood and duck blood, a mixture of duck blood powder and gelatin to replace pure duck blood. Fresh pig blood is darker in color, and an appropriate amount of carmine and other additives and preservatives are added to it, as well as an appropriate amount of calcium salt to make duck blood tofu for sale. Mix the duck blood powder and gelatin thoroughly, and add an appropriate amount of salt to precipitate.

The difference between the two. There is a big difference between normal duck blood and fake duck blood, which can be distinguished by color, structure, flexibility and taste. The surface of duck blood tofu made with fresh duck blood will appear dark red, while the fake duck blood will appear bright red; the size of the pores inside the condensed duck blood is different, while the pores inside the fake duck blood will be uniform in size or there will be no bubbles at all. ; Steamed duck blood is easily broken, while fake duck blood is more flexible and will not melt after being cooked for a long time. In terms of taste, real duck blood tastes like tofu, while fake duck blood tastes like jelly.