I have read countless articles and posts about alumninum pots and pans becoming black after only boiling some water in them. Most writing focus on ways to clean them. However, I am only interested in knowing WHY do they turn black.

We are not talking about greasy food over-cooking. You only put water in the pot, and after boiling the water the water and/or the pot turns black !!!!!!

It maybe hard water or whatever but I need toi understand this, preferrably in chemical terms. Is the black material dangerous or toxic ?? Are there other aluminum pots that do not turn black ??? etc.

The issue is important for preppring cookware for a BOB. Aluminum is lighter and cheaper , but stainless steel is worry-free in this regard.

Thanks

I wouldn't say "black". Darker, yes, but it's more of a discoloration. I think of black as in cooking over a wood fire. That's black.

I don't think the discoloration is a big deal, at least I've never heard of any issue over it. Maybe others with a chem background can chime in on this...

HJ

A definitive answer to your query requires a real chemist. But do remember that various compounds are dissolved in the water you are boiling. You are probably observing the reaction of that material with the aluminum. I have encountered this on occasion; all I can say is that it cleans up readily. I have used aluminum pots for decades, and all of them are as shiny as when they were new.

Stainless cookware is heavy, strong and cheap; aluminum is light, cheap, and not incredibly strong; titanium is light, strong, and expensive.

Light, strong, cheap - pick any two.

lol. Yep, that's about the size of it.

HJ

The only black I've seen is on the outside where sooty fuels leave deposits. I generally leave it be if its not so thick that it threatens to smear over everything. In that case I wipe the worse of it with sand.

The Coleman Fyrestorm Hard Anodised Cook Kit @ around $10 is great value and is tough, reasonably lightweight and strong

http://www.coleman.com/coleman/ColemanCom/detail.asp?CategoryID=31009&product_id=8552-305

The pots will not darken as they are already hard anodised and are just as tough as Stainless steel. They also come with a very good non stick inner coating. The fit and finish are excellent and the bottom of the pans have grooves so that they don't slide of the top of the gas stove.

I'm pretty sure the blackening effect is just a simple oxidation reaction. My aluminum pots always darkened with use. And when anyone used a aluminum-shafted paddle during a day on the river, they always had black hands. Sure, it's a nuisance, but I sincerely doubt it's in the top 20 things that will kill you.

BTW, anybody who uses anodized/hardened aluminum pots: does this have the same effect on the flavour of food/tea/coffee that the old aluminum pots used to have? Very interested in your experiences.

Hey thanks everyone for the responses

The reason I want an answer in chemical terms is that I have read somewhere ( FWIW ) that LEAD is used in these pots as a prt of aluminum lead alloy. I don't know why lead would be used because aluminum itself is soft enough and can better handle the high temp than lead. It may be just another one of those ( someone said ) very common over the net. But in any case, I wanted to be sure, especially that I have checked the theory of aluminum oxidizing during cooking . I found that the color of aluminum oxide is WHITE !!! So, what is this blackish stuff ??

In addition, I am thinking of buying some of my BOB cookware from $1 stores ... very cheap and almost disposable. Some will go in my survival caches. Also, I am thinking to include those disposable pots made of thick aluminum foil ( can be folded in a kit and better to use for boiling water than a foil) So, does anyone think that those cheap ones may contain lead or any other harmful stuff ?

And while we are at it ...
Many preppers on U-tube and others talk about cooking in cans (like bean cans) , but I have heard one of those ( someone said ) that welding material in those cans have some lead-tin alloys. Anyone can confirm or reject ?

Probably just reaction of aluminum with minerals in water, nothing to worry about.

OK, I can understand that but it chould make sense.

For example, someone said the aluminum reacts with phosphate in the water . But when I checked the color of aluminum phosphate , it was white ?? So, the colored stuff isn't aluminum oxide, not aluminum phospahte. What is it ?

I use anodized aluminum both at home every day, and in my daypack. It does not react or put metallic tastes into food like some of the old shiney aluminum pots did. Heres a link to some information.

http://www.only-cookware.com/what_is_anodized_cookware.html

Bolded for emphasis is mine. When you say stainless steel is cheap, you mean relatively I assume? As in compared to Titanium? I only ask because a few years ago I got a deal on two stainless steel mess kits that were on clearance at a big box store. They were replaced by aluminum mess kits that were about the same price point. Upon searching around trying to find a third stainless set (I don't like the aluminum sets in spite of the weight savings), the price was double what I paid for the clearance sets and what the current rate is on the aluminum sets. I am just too much of a cheapskate for my own good I guess. Probably a big reason why I have not shelled out for any titanium gear to date.

Anodized aluminum doesn't fit in to the quote. It's more expensive than ordinary aluminum but not as expensive as titanium. It's stronger than ordinary aluminum and similar in durability to steel. It is not as light as ordinary aluminum because the cookware tends to be thicker than aluminum pots.

In short it middling of all three adjectives. I use it and love it. It cleans out really well. My 8" fry pan is non-stick as well but it's only big enough for 1 or 2 pan fish. (2 sets of GSI cooksets and 1 GSI fry pan)

The annodizing process itself is not adding significant thickness to the aluminum (~.005" thick at the most). As for strength, the anno will only increase scratch resistance, and the weight gain will will not be measurable. The only reason an annodized pan would be stronger/thicker/heavier is because it was built that way, the annodizing would have no effect.

I prefer stainless but Anodized aluminum is my second choice. Apparently The anodizing gets rid of a bunch of the concerns with aluminum. Just Dont let anodized rub to anodized, its a quick way to loose the finish, Just ask my two streamlights i had in one pocket </3.

I was told years ago that the aluminum we use daily isn't really pure aluminum, it's mixed with other metals. And there are minerals in the water, and in the foods we cook. With all those mixes of minerals, some are sure to react with some of the others.

The guy that told me this (a machinist) also said not to worry about it: if I'm not vomiting within five minutes of eating out of it, it can't be too poisonous.

Sue