In my home country, ground beef is typically made with an assortment of offal and has a relatively high vitamin/mineral content. And a chewy texture that I personally believe requires an acidic spice marinade and grilling to be palatable.

This really isn’t relevant, but your anecdote made me imagine feeding spicy kebabs to guinea pigs and I couldn’t help but feel a mix of horror and confusion at these poor imaginary creatures deriving more nutrition from a hot spice blend than from the kebab itself.