Washing yer dishes.

When I use Palmolive, or some other arbitrary dish soap, fill my sink with hot water first then add the detergent rather than add soap while the sink is filling. I find the bubbles annoying because I can see the spots I miss while I scrub. Suddenly I thought… are these bubbles necessary? If I’m not mistaken, the detergent is an emusifier to help break up greases and oils. I don’t think the powdered stuff I put in a machine dishwasher creates bubble like that… though I haven’t put any in sink water to test it out. So whats the straight dope? Does dish soap have an added ingredient that creates bubbles to make us consumers think there’s something greater at play?

Put the soap in after the sink is filled. The water pouring into the sink is what is causing the bubbles to form.

Dish washer soap isn’t bubbly at all. Those bubbles will fuck up your whole operation.

I don’t know about the bubbles doing a better job or not (in the sink) but I swear by Dawn…it doesn’t wear out as fast as Brand X and I use less.

I think the bubbles are an added ingredient to the soap, too.

And I think you’re right, that they aren’t really required for the cleaning process.

Detergents are not all the same. Some are high foaming and some are low foaming. Dishwasher and HE laundry detergents are designed to be low foaming. Hand dish soap is designed with a high foaming detergent, and can also have stabilizers to keep the foam together.

The bubbles are not necessary for cleaning, but they can help you to know when the detergent is all used up. Imagine a dishsoap that makes exactly zero bubbles, it would be difficult to know if you have used enough, or if its cleaning power is spent. Not an issue with your dishwasher or washing machine, since you put a measured amount in and walk away.

Yeah, it’s an emulsifier and wetting agent. It makes your water wetter. I can’t think that bubbles help indicate whether the “cleaning power” of the detergent is gone or not, though. I imagine the “cleaning power” is gone when you can’t wash the dishes anymore. Strictly speaking, soap isn’t required at all if you can get the dishes clean without it. The whole function is assist you in getting the crud off of the dishes, making them clean. Sure, I think some brands brag that they have anti-bacterial additives and so on, but that’s a secondary function and not all that important anyway.

RE: bubbles

Somewhere in the back of my mind I seem to recall a discussion of bubble’s purpose. Something about the shape of the bubble and the chemical properties of the fluid actually had something of a mechanical effect on removing dirt. You can tell from that just how dark and dusty the back of my mind is… but does this ring any bells or am I conflating two ridiculously separate subjects?

My WAG is that, bubbles or no bubbles, putting the detergent in while the water is running helps it to be better distributed throughout the entire volume of water, thus getting on your dishes more evenly.

I guess it depends on how you do dishes. I put soap in the sponge, rather than in a dishpan. When the sponge isn’t making bubbles anymore, I put more soap in. The existance of the bubbles tells me there is still soap in the sponge.

Without that, I’d be washing something, it won’t get clean, and I have to re-wash it with more soap.

There is a cute little gadget that is basically a sponge with a hollow tube attached to it. Liquid soap goes in the tube, and you sponge the dishes with it.

Actually the whole function is removing oil and grease. Water alone can’t remove oil, it needs an emulsifier to get the oil to ‘dissolve’ into the water and wash away. And a given quantity of soap can only emulsify a certain amount of oil; after that, the soap really is all used up, and you need to add more soap. So paying attention to bubbles does make sense as a way to know when you need more soap.

I mean, you can ‘wash’ dishes without soap, but if they had anything oily on them, they’ll still be greasy afterwards. And old grease rotting on dishes isn’t usually good for you.

What if it’s bacon grease?

Mmm, bacon.

The detergent is formulated to make bubbles, because that is what the consumer wants.

It is easy to make a formulation of surfactants that does not foam and has highly detersive properties, but people want to see bubbles.

I have no cite for this.

I remember hearing a lecture on marketing, and one reason that dish soaps were designed to produce lots of bubbles is that it helped hide the “sink full of dirty dishes” and also “showed” the soap doing something. (Lots of bubbles means better soap, right? ((Not so, actually, but marketing and facts are at best a wink away from larceny anyway)) - chemically, it is the detergent disolved in the water which helps to loosen grease from its bind on the surfaces… the “suds” is just more stuff to rinse off…).

By the way, don’t use dishwashing machine detergent to hand wash dishes unless you want chemical irritation/burns to your skin. It is a LOT stronger than regualar dish soap.

Regards
FML