I do not. I didn't make myself clear in first comment. Sorry for that. I was talking about using same water for a whole week. I felt that it is not optional. The residue building at the bottom, open space of messy kitchen with lid open and constant reheating because it cools overnight is what seems little bit off for me.

Oh, I see - yeah I've never heard of a restaurant using the pasta water across days. I don't think that's a thing. In fact it's a whole thing about how the pasta gets better throughout the day, because you start with fresh water each day. And remember that water is constantly being added to the pot as it gets soaked up by the pasta.

Just from a food safety perspective I'm not sure it's legal to reuse across days, given that it's going to take all night to cool, only just in time to be reheated again.

If it’s constantly at a boil I doubt there’s a food safety issue though high volume pasta shops probably don’t need to keep the water more than a day

Ahhhhhh, I also misunderstood your comment. Yeah, I hear you. Maybe you can keep the starch water in airtight container...not sure. I don't keep starch water for the next time I'll cook pasta. I just use the currently made starch water to create a sauce. Highly recommended! But, as mentioned in the research, wait for the water to cool down a bit. Or make a risottata in a pan. <- also highly recommended if you have a pan big enough.

I guess you don't wash flour, but it does need to be disinfected (eg by cooking it) - it's a little unsafe to eat raw, which is the problem with raw cookie dough.

If there was a way to get rid of the insect eggs people would presumably want to do it too, but iirc they're just too small to filter out.