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Author Topic: Is Washing Dishes with Cold Water as Effective as Using Hot Water?  (Read 22531 times)

BJMarshall

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My wife seems to think that one must use hot water to wash dishes, and she disapproves of my using cold water. I am under the impression that it's the scrubbing action with soap and a washcloth that cleans the dishes rather than the temperature of the water. Does anyone know the science behind washing dishes by hand?

Regards,
BJ

graham.d

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Generally speaking heat helps quite a bit. Nearly all chemical actions are more active at higher temperatures and so would aid the detergent action in removing unwanted substances. It also causes fats to soften and melt permitting greater penetration of the water/detergent mix. From personal experience it is definitely easier and much quicker to wash dishes in hot water.

I do note, however, that some washing powders (for washing clothes) are said to be designed for washing cold. Although this may be also a way of saving energy, the detergents may not be so eco-friendly and a main reason is because of the lower risk of leeching colours from fabrics.

Geezer

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It doesn't really apply when you wash dishes by hand, but when you use a dish washing machine, the temperatures are high enough to sterilize the dishes. An even better aspect is that they don't get contaminated with a dish towel while drying.

graham.d

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It doesn't really apply when you wash dishes by hand..

It does in my experience. In particular if you are cleaning baked on fat and carbon off a glass dish that has been in the oven. Your wife is obviously kind to you :-)

Geezer

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Absolutely! Hot water is far more effective when washing dishes by hand, but I don't think the temperature will be high enough to do much sterilization, unless of course you have a pair of asbestos lined rubber gloves like the ones my wife got me to stop me complaining.

 

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