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Comment by exabrial | Hacker News Reader

I would probably _not_ do this long term without expertise from someone that understands the 'why' on the ingredient list on commercial detergents... but my limited intuition says it's probably ok in the short term. The hotter the water the better, and always dry as hot as possible. Dishwashers save a ton of water, definitely use them when available

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I have a degree in chemistry. This is probably fine unless used constantly or in excess, or if you water is too hard. Powder dish detergent contains sodium carbonate, which is more basic than sodium bicarbonate (baking soda). Bicarb is less soluble and thus acts as a very mild abrasive, but powder detergents usually are similarly abrasive, though I can't find any hard sources saying bicarb is completely safe.

Biggest issue would be hard water creating gunk buildup in the plumbing. Run the "good stuff" every now and then with drying agent and that should clear it out.

If you swap bicarb with sodium carbonate (washing soda) you literally have dishwasher detergent that might be a bit foamier.

Why dry as hot as possible? I was always told that the dry cycle was a waste of energy unless you need the dishes dry faster.

Sanitization. Your dishwasher spreads dirt and bacteria around and tries to remove as much as possible with a clean water rinse. Bacteria get into every micro-pore and nano-sized crack, where detergent is unlikely to penetrate effectively. Heat doesn't discriminate (unless we're talking prions, but I digress) and will kill everything that remains.

Does it really get to 150°F inside a dishwasher?

Sanitize mode on Bosh gets to 155°F, They claim it kills 99.9% of bacteria.

Korean dishwasher have heat and UV lights.

I can't see how that's true. A quick search tells me that dishwashers can get up to a max of around 60c, that's nowhere enough to kill most bacteria, especially ones hiding deep inside cavities. Maybe you could pasteurize milk in an extra-long run of your hot cycle, but it won't come close to sterilizing stuff.

Fair enough, but let's say the goal isn't to kill everything, but common bacteria that causes problems, such as salmonella and e coli. 60c is enough to handle that.

It's non-issue in any case. Quite a few people on the planet really need to sterilize their plates, spoons, and forks just to have a lunch. And with rare exceptions 60°C + soap is more then enough for all that stuff to be safe.

60°C is enough. I've made chicken at 60°C in a sous vide without any issues

Here's the pasteurization table:

https://www.seriouseats.com/2015/07/the-food-lab-complete-gu...

So you need to hold at 60 degrees for an hour. Even assuming the dishwasher isn’t lying about it’s temperature, it’s unlikely to do that.

Edit: looks like some dishwashers have modes that do this, though they take a very long time.

I haven’t seen any quality evidence that dishwasher dry cycles effectively “sanitize” anything. Really not trying to be a “but actually” dick, but without this information it’s just marketing mumbo jumbo.

Here [1] is a reference of a citizen experiment to test the sanitize cycles. There are also experiments regarding clothes and apples that are quite interesting on this website.

[1]: http://www.dranniesexperiments.com/dishwasher-testing

They get contaminated as soon as you unload the machine.

Instead of using the dry cycle, use hot water to wash and rince and open the door when its done... It dries most stuff for free (except plastic)

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