Blood as Food

There's a scene early in The Name of the Rose involving barrels of pigs' blood. It was autumn, and time to slaughter the pigs, but of course you wouldn't want to waste the blood.

You could not, however, just let the blood pour into a container and sit, because it coagulates quickly and becomes unusable. If you intend to try any recipes using fresh blood, remember that you must immediately stir the fresh blood constantly while it cools (if you've ever made a hollandaise, you'll know how tedious this can be).

Vinegar or wine could also be added to the blood. The acidity in them lowered the pH and slowed bacterial growth, keeping the blood smooth. (Consider this site if you want modern pointers on this process.) None of this is unusual for cultures that used every part of an animal. Blood was a rich source of protein as well as flavoring.

As for the actual use of the preserved blood? It acts as a binder, and could be used to give texture to a broth. It could also thicken a sauce, but blood curdles when heated, so it would be stirred into a sauce just before serving.

Casual reading about life in the Middle Ages will often turn up references to black pudding, made with pork sausage, pigs' blood, and suet. Blood sausage was made by combining blood with oatmeal, suet, breadcrumbs, and spices, then stuffed into casings (cleaned-out intestine), and allowed to cool and "set." Once parboiled then chilled, they could last awhile before being eaten. (The picture here comes from this site with a detailed recipe.)

Tomorrow I'll share some recipes from different medieval cultures.