6

I want to order a custom-cut steel plate to use like baking steel in the oven, and I read that in common raw steels the trace amount of lead can get up to 0.36%.

If I season the steel like I would cast iron, and only use it to make pizza and bread on it, could that trace amount of lead be harmful?

Edit: I just found out that 0.35% is the allowed amount of added lead to machinable steels. The maximum amount found in common raw steels is limited to 0.1%, and in practice probably a lot lower than that.

user48884
  • 183
  • 4
  • 1
    I'm pretty sure that yes, it will harm you and you should get a food grade steel plate to be on the safe side (anyway, just buy a stone plate, why would you use one made from steel?). – Nobody Aug 01 '17 at 09:48
  • @Nobody because the thermal conductivity of steel is more than ten times that of stone, and the thermal capacity is great as well. Stone does its job in an actual pizza oven, but at the relatively low temperatures achievable in a regular oven, steel is much better. – user48884 Aug 01 '17 at 09:51
  • I've always had great results with a stone plate at 230°C (definitely a regular oven, nothing professional) but that was just an aside. – Nobody Aug 01 '17 at 09:54
  • @Nobody the crust I get from cast iron pans is far superior than what I get from stone, my only complaint about it is that its not flat and only 15 inches. And as to why I don't buy a baking steel; it's a lot of money for a slab of steel... – user48884 Aug 01 '17 at 10:21
  • 2
    This is a non-issue. *How often* and *how much* actual material do you think migrates from the steel plate to the food? And from that 0,1% may be lead... –  Aug 01 '17 at 11:18
  • 4
    Safety is a relative term. Is skydiving safe? Yes...Is it free from risk? No. Is using non-food grade steel 'safe'? probably, but how much are you willing to gamble? Yes, the thermal conductivity of steel is 'greater' but the through put is also much faster. One of the advantages of stone is that it radiates the heat into the dough in a more regulated fashion. I expect the result you would get from cooking pizza on steel is that the bottom of the crust would burn before the cheese on top would melt. You asked about 'safety', and that answer is 'it depends'. Is it a good idea? Probably not. – Cos Callis Aug 01 '17 at 12:40
  • Why don't you contact the company and ask them about the steel? They should know about their products – GdD Aug 01 '17 at 15:23
  • Not sure if it would make it safe or not, but how about a piece of parchment paper between your dough and the steel? At least the dough wouldn't be in direct contact with the steel. – Cindy Aug 02 '17 at 13:50

3 Answers3

6

I, and in general we, cannot answer if something is safe. There are instances where we can say something is clearly unsafe, but when dealing with things like is this piece of metal safe for cooking we are not equipped to give anything but anecdotal answers and partially informed opinions.

The only safety answer that is actually reliable would come from lab testing and that is why we shell out tax dollars and public funding for organizations like UL and USDA in the US and similar organizations in other countries. They do testing and declare metal products, glass, plastics, etc. to be food grade or not food grade according to their composition and reactivity to normal food products. They are not always correct, but their declarations are made from testing results, not guesses and partially informed opinions, mine or anyone else's.

Also an opinion, but one that I think is really the only prudent and reasonable one to make is get a product that is rated food grade, not a custom made item you or others think is safe. The amount of toxins in the metal may well be low, well within standards, but that does not say it is not in a reactive form which will enter you food on first contact with a slightly acid item, and lead may even be one of your least concerns. A piece of steal which was not manufactured under food grade conditions could have many other toxins that are not permitted in food grade manufacturing, permitted because they are in low amounts that are safe for the intended use but become readily transferred to food.

dlb
  • 8,663
  • 17
  • 34
  • Would you know how to find out which steels are food-grade? I have been doing some research for quite a while now, and I can't find anything about which kinds of steel are okay in the EU. – user48884 Aug 02 '17 at 09:02
  • 1
    @user48884 I would think as GdD suggested, the manufacturer should be able to tell you, but really only if you trust the manufacturer. If they cannot tell you, then you have to assume it is not food grade by default. If the manufacture makes other food grade items and use the same base stock for a custom cut, then you are OK. If they make just regular industrial steel item though, not so much. – dlb Aug 02 '17 at 20:28
  • +1 stick to food grade items. There could be other problems than lead to be concerned about. – Wolfgang Aug 03 '17 at 20:10
1

Unless you are paying a premium for "free machining" steel , there is "no " lead in it. Normal steel will have < 0.02 % lead. And "free machining" plate or sheet would be a very unusual product ; free machining is typically bar product , most likely containing sulfur and maybe lead.

blacksmith37
  • 1,095
  • 1
  • 7
  • 12
0

Numbers aside, with the amount of steel that most food comes in contact with during packaging, processing, and shipping, your baking sheet would be the least of your concerns.

ChefAndy
  • 3,053
  • 9
  • 15
  • 5
    But that is specifically 'food grade' metal (stainless steel, aluminum, etc) – Cos Callis Aug 01 '17 at 15:04
  • 1
    Belief with it being OK to use non-food grade in cooking to me is akin with belief in the 5-second rule for items dropped on the floor. – dlb Aug 01 '17 at 18:11
  • 2
    "Food Grade" got my interest , since I have never seen it in a specification. I checked the ASTM index , there are no :food grade" material specifications..( I was on the ASTM steel committee a few years ) .However the 304 and 316 family of stainless totally dominates the food industry. Today duplex stainlesses must have some applications because of the 304/316 Achilles heel of chloride stress corrosion cracking. ASTM A-270 Stainless Sanitary Tubing , intended for food and dairy industries is the only spec with a scope for the food industry. It has no special requirements. – blacksmith37 Aug 03 '17 at 23:35