I have been thinking about this question for a long time. Is blood safe to eat or Is blood dirty? I will not include explanation about religious belief. Its all about scientific explanations.
Animal blood has become one of the popular street food, the inihaw na dugo. It would be dirty if the process of animal slaughter is unsanitary, including the preparation and cooking.
Let assume that all processes are done in the cleanest way possible. Can we assume that blood is not dirty and safe to it?
What is blood anyway? It is similar to vehicle, carrying passengers from point to point. Blood as a transporter carries different substance through out the body. Blood might really be dirty depending upon the situation or their function:
1) It distribute oxygen to all tissues.
2) Take out carbon dioxide away.
3) Distributes nutrients to all body parts.
4) Take out all harmful substances or unwanted materials.
5) Fight infections and tissue repair (e.g. blood clotting)
The blood might really be dirty when it is doing function number “4” – taking out all harmful substances or unwanted materials. The hard part – we cannot separate blood according to five functions mentioned.
Is blood of some animals cleaner than others? It might be. Cows and goats only feed on clean grass. Grasses has almost no waste substances so their blood will carry less. Other animals feeding on decaying creatures could have a really dirty blood. The same is true for animals grown on commercial feeds.