Guess what parts of the animal makes it into your delicious salty hot dog? Well, some researchers, back in 2008, wanted to know if they could find out, based on taking thin slices of various brands of hot dogs and looking at them with a light microscope, an electron microscope, and using various other techniques. And they were successful in identifying most of what goes into the average hot dog.
Package labels indicated that the top-listed ingredient in all 8 brands was meat; the second listed ingredient was water (n = 6) and another type of meat (n = 2). Water comprised 44% to 69% (median, 57%) of the total weight. Meat content determined by microscopic cross-section analysis ranged from 2.9% to 21.2% (median, 5.7%). The cost per hotdog ($0.12-$0.42) roughly correlated with meat content. A variety of tissues were observed besides skeletal muscle including bone (n = 8), collagen (n = 8), blood vessels (n = 8), plant material (n = 8), peripheral nerve (n = 7), adipose (n = 5), cartilage (n = 4), and skin (n = 1).
Plant material? I hope those were not hot dogs that advertised “All Beef” or something similar. Rest assured though, that more expensive brands had more meat, and brain tissue was not found…
In conclusion, hotdog ingredient labels are misleading; most brands are more than 50% water by weight. The amount of meat (skeletal muscle) in most brands comprised less than 10% of the cross-sectional surface area. More expensive brands generally had more meat. All hotdogs contained other tissue types (bone and cartilage) not related to skeletal muscle; brain tissue was not present.
h/t NCBI ROFL