We have never encountered information that indicates that ketchup contains blood or any other animal-derived ingredient. It is possible that the “natural flavors” in the list of ingredients could be animal-derived. Contact the manufacturer of the brand that you are interested in to inquire about the source of the natural flavors. Organic ketchups are likely to be free of additives that may contain animal-derived products.
According to the Heinz Web site (under “Heinz Products”) “Heinz ketchup has never contained any animal products.” The site goes on to say that “the FDA has set a standard of identity for ketchup that does not permit the use of any animal products. Any deviation from this standard of identity would mean that the product could no longer be called ketchup [or be] sold legally under the name ketchup.”