Dish Washing Question

Has anybody come up with a soap that is suitable for washing dishes whether they are in your sink or in a dishwasher? I realize these are very different washing environments, but presumably there is some middle ground somewhere. From reading thisI get that you might use too much of the low sudsing stuff that works in dishwashers when washing dishes in the sink, but how different can it really be? You’re still just washing dishes. Can someone please fight my ignorance?

No one has, because the conditions of use are significantly different. Maybe you’ll find this more helpful than the site you linked. In a nutshell, dishwasher detergent can damage your hands and dishwashing liquid can damage your dishwasher (machine).

Aw hell, I misread my own link. I’ll try to find a more applicable one later.

The issue is the customers. Customers mistakenly believe suds are the thing that cleans dishes. They don’t. Witness the fact a dishwasher machine makes almost zero suds and cleans just fine.

Any dish detergent that worked well in a dishwasher would make so little suds that the consuming public would be unwilling to believe that it’s working.

Manufacturers have tried packaging mayo in ketchup-shaped bottles and ketchup in mayo-shaped bottles. The public won’t buy it even though it’s the same exact same name brand product.

It is *very *expensive to educate the public to change its habits for something that’s not an obvious major benefit. If somebody invented a totally new gizmo, it’ll catch on. But a slightly different variant with no obvious benefit? Not gonna happen very often.

Thanks everyone. Ignorance fought.

So how to low-foam detergents work, anyhow? For all the detergents I’m familiar with, the chemical properties that make them good detergents are the same that allow foaming. E.g. they’re typically long molecules with a hydrophobic bit on one end and a hydrophilic bit on the other end. This allows them to form micelles in solution that can dissolve greasy molecules, but it also allows them to stabilize the air-water interface in bubbles.

What are the chemical properties of non-foaming detergents and surfactants that lets them dissolve insoluble molecules without also stabilizing bubbles?

I read somewhere (no cite, sorry) that dishwasher detergent is both caustic and abrasive. That’s why you should not put antique china or non-stick pans in a dishwasher; the surface will eventually be etched or abraded away. Also, a dishwasher can use water that is much hotter than your hands could deal with, so some of the cleaning is simply due to high-pressure extremely hot water.

This is a terrible analogy. Ketchup pours. Mayonnaise spreads. They have distinct containers for good reason. Mayo in a glass ketchup bottle would not work at all. It would be like a mean prank. Ketchup in a mayo jar would just suck and be inefficient. Plastic squeeze bottles are the equalizer, but they’re not really equal.

Squeeze bottles are great for mayo as a condiment. I keep one in the fridge at work for sandwiches. They’re terrible for using mayo as an ingredient, and mayo is used as an ingredient far more than ketchup. Ketchup is mostly a condiment, but even when used as an ingredient, it’s much easier to squeeze out of a bottle to fill a cup than it is with mayo.

The fact that mayo in squeeze bottles is more $/oz. is evident proof that Hellman’s/Best Foods know that it’s a niche demand. As far as ketchup goes, I’ve never seen a jar of Heinz. Implying that consumer quirks determine the mostly distinct containers of these products is flat out wrong, in my opinion.

Years ago Heinz DID package their ketchup in squat glass bottles. It was great if you needed large quantities in a hurry, but otherwise it was a disaster. The wider mouth got all gunky, and after awhile it just looked sad and dirty. It disappeared from most shelves.:smiley:

Dishwashing liquids are predominantly detergents- things like sodium lauryl sulfate and sodium laureth sulfate and similar compounds. Dishwasher “detergent” is often not even detergent, strictly speaking, or if it is, the detergent component is a small one.

Here’s the ingredient listing for Cascade Action Pacs Note how none of the “cleaning agents” are actually detergents- the formula is more like a highly modified version of Oxiclean.

This is the ingredient listing for Dawn dishwashing detergent It’s loaded with detergents and solvents, but no enzymes or other particularly interesting stuff.

Part of this is due to the very different mechanisms- hand washing only relies on the detergent to break up and disperse grease so it can be rinsed away, and to penetrate crud on the dishes to allow them to be softened up. Most of the actual crud removal is done by your sponge, brush or cloth using elbow grease. Dishwashers have to do it differently- for the most part, the jets aren’t quite so powerful that they’ll just remove everything by themselves, so the actual detergent product has to be that much more effective (often using enzymes and harsh chemicals), and they have to use higher temperature water and a longer cycle.

No the dish washer is not abrasive. Hydroxide will attack glass and other vitreous stuffs, and the glue layer under the non-stick. Also the high temperature may cause water vapour to form in the non-stick layer… gas pressure will lift off the layer.