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by pedantsamaritan 2134 days ago
I think most dishwasher detergents switched to enzymes to replace phosphates: https://www.cnet.com/news/appliance-science-how-dishwasher-d...

That article implies the enzymes do some work, so that surfactants/soap can carry away the tougher components (protein and starch)

3 comments

Yes, there can be a lot of additional ingredients added to dishwasher soap and I had heard of enzymes before.

I have to admit I'm a bit skeptical of their effectiveness. Enzymes can usually be denatured pretty easily and if they are in a solution of hot detergent, I'd be amazed they'd stay intact enough to actually do what enzymes do.

That said, there are enzymes that are pretty robust, so I could be completely off base.

Edit: I am off-base, apparently there are super stable amylases that can survive 106C water.[1]

[1]https://www.sciencedirect.com/science/article/pii/S157096391...

I could believe the enzyme bit. Soaps require 3 things to work well: sheer force, concentration and temperature. The higher the better for all 3.

Dishwashers can’t do consistent sheer force unless the sprayer hits your dish just right.

So makes sense that their cleaning agent will use some other mechanism just requiring application/soaking and not sheer force.

Dishwasher powder is also extremely alkaline, i believe. I (cosmetically) ruined an aluminium Moka coffee pot by putting it through a dishwasher.
Nothing cleans quite as good as strong alkaline. In the lab, we'd use a 50% lye bath and it strips off everything.

If you want to add a bit of punch, you can add some 30% hydrogen peroxide as an oxidizer. Caution is needed as mixing a strong oxidizer and organic material is a recipe for fire or an explosion.

> Nothing cleans quite as good as strong alkaline.

Depends on what you are cleaning. Most oven cleaners are strong alkalines, often sodium hydroxide. They work well enough on grease, but neglect it a bit and the heat turns the grease into a char that nothing short of a steel scraper and lot of elbow grease will remove. (On reflection, that char may be a combination of what was grease and protein.) In any case, alkaline cleaners and soaps won't touch it.

But allow to ammonia at it for 12 or so hours (it doesn't have to be wet - just exposed), and it just wipes away. The usual technique is to put the stainless steel fittings in a garbage bag, pour in a cup of cloudy ammonia, and tie off overnight. (If you want to have working nostrils afterwards, open bag outside.)

It even works on the glass door. Open so it's flat, cover with paper towels, soak paper towels in cloudy ammonia, hide outside for an hour so the smell doesn't take you out and burnt on crap wipes off.

I don't the chemistry is, but it's magic. It would be interesting to find out what the chemistry is, actually.

Yah, lye won’t just clean, but also help make new soap from anything fatty!
I speculate that bio laundry powder would be better than dish soap, as that has similar enzymes in. No idea if it's similar enough, or if there are other things in laundry powder that would be a problem.

Oh no, hack trouble:

https://www.idealhome.co.uk/news/washing-machine-hack-242903