The video claims the smell is not "entirely unpleasant" but that's a lie. It is the most disgusting smell I have ever encountered. And I used to have to shovel manure and clean chicken coops growing up. Once I even had to dig a dead racoon out of the guts of a square baler after it got run over and jammed up the machinery and then sat for a few days in the summer heat. Garum smells worse.
Fish fertilizer is the worst smell I have ever smelled. Similar to how our dogs smell after they've rolled in rotting salmon carcasses on a stream bank.
On that note, the easiest way to get your hands on some protease is to buy digestive enzymes sold as food supplements (most often they're made out of dried pork pancreas).
You also don't need much equipment: scales and an immersion circulator should do the trick.
For fish sauce definitely, assuming you also use the guts so you can get the enzymes. If you want to make with a protein source that doesn't have the enzymes present, like mushrooms, you can add them separately. Whole fish just fills the protein and protease slots with a single ingredient.
I've been wanting to make my own fish sauce for years at this point. I even found a huge crock to do it in. I've just never gotten it together to go to the fish market super early and source fish. What species do you use?
I've made a few batches of salmon garum that turned out nicely. Just make sure you use raw and not cooked, as the cooked fats will taste rancid. It tastes different than asian fish sauce or colatura but still of use in similar contexts.
