Researchers have discovered the reason cats, which evolved in the desert, love tuna so much. Link to the LiveScience article here.
In a study published in the August issue of the journal Chemical Sense, researchers found that cats, like humans, use taste receptors that detect umami — one of the basic tastes alongside sweet, sour, bitter and salty. But unlike human umami receptors, cats' taste receptors bind to two chemicals found in particularly high concentrations in tuna. These chemicals enhance the umami experience for cats, making them strongly prefer the fishy treat.
Umami is what gives food a savory or meaty flavor, so it makes sense that an obligate carnivore like a cat would prefer its taste.
Tuna contains the nucleotide inosine monophosphate, which bonds very strongly to cats' specific umami binding site. Tuna also contains far greater amounts of the amino acid L-Histidine than other fish and other meat sources, and that is "an essential amino acid for cats, and a strong umami enhancer."
This level of detail, on a molecular level, of cats' taste preferences can drive the formulation of more appealing cat food and even medicines.
This study prompted John Bull (@garius.bsky.social) to post this amusing post to Bluesky: