Personally, I think the reasoning is vastly more prosaic.
The primitive people who are described in the Hebrew scriptures believed that the soul was in the blood. No doubt this was because you could drain the blood from a small wound in a person and that person would die. Thus, the soul, the life, was taken by these simple savages to be in the blood.
Also, remember that Jehovah - the giver of life - was the only being who could demand that life be taken and returned to him. So if you drank blood, you were depriving Jehovah of his due.
Now I suggest that here in the twenty-first century we should have so enlarged our concepts of God as to have abandonded these childish teachings that a) blood contains the soul, and b) God is interested in exercising any sort of property title to five pints of slick red bodily fluid. It would make more sense to say that the soul existed in the sperm of men and the eggs of women would it not? But then that would surely lead literalist biblioators to other absurd teachings.
When I was severely injured three years ago, and almost died from internal hemmorage, I was transfused with three units of whole blood. I felt no guilt, no compunction, no bad vibes from God. But if I even seriously THINK about doing something that my internal knower knows is wrong, like lusting after my next door neighbor's wife, I get special delivery messages from the small still inner voice - like right NOW!!!
That's a good enough indication for me.