Kitchen Utensils: Safety, Quality & Design

[Oxygenne]

I was buying some spoons and forks and knives made in China.
Very nice and attractive design and it was written there stainless steel.
After I was using them 1-3 times now I see a reddish-brown-colored under the so called stainless steel and I have no idea what is but I guess is copper and I am scarred copper can be poisonous and even fatal to organisms.

Do you think is good to continue to use them ?

Also if I will buy another how to know are better.

 

[JasonRox]

I was buying some spoons and forks and knives made in China.
Very nice and attractive design and it was written there stainless steel.
After I was using them 1-3 times now I see a reddish-brown-colored under the so called stainless steel and I have no idea what is but I guess is copper and I am scarred copper can be poisonous and even fatal to organisms.

Do you think is good to continue to use them ?

Also if I will buy another how to know are better.

If you're concerned about products from China, why the hell are you buying them?

Sure it said Stainless Steel, but you practical implied that you had doubts. But I guess you bought it because it was cheap. Money overrides everything.

I would say buy some that are from Canada or the US. That should be good.

 

[zoobyshoe]

Do you think is good to continue to use them ?

No.

Also if I will buy another how to know are better.

The kind of stainless steel used in utensils in magnetic. Copper is not. Bring a magnet to the store.

Also, try a magnet on the ones you have. They could be chrome plated steel, in which case the brown is common rust, and the claim you read on the package was actually just "stainless", and not "stainless steel". I would bet this is the case since copper should oxidize as a blue green crust.

 

[Moonbear]

My guess is the reddish brown is rust. If they were cheap, it's unlikely they are solid stainless, but are just plated with it. When it got scratched enough, the exposed metal beneath started rusting.

 

[Moonbear]

They could be chrome plated steel, in which case the brown is common rust, and the claim you read on the package was actually just "stainless", and not "stainless steel".

Ah, yes, that's most likely.

 

[FredGarvin]

I'll give the manufacturer the benefit of the doubt and say that the material was chinced on the chromium. For steel to be considered a stainless steel a minimal amount of chromium as alloying element is 11%. Most likely they tried to get the bare bones minimum and were a little under, hence the rust. It's definitely not copper.

I thought 18-8 was the common material for most utensils. It's one of the 300 series austenitic stainless which is not magnetic. The 400 series is magnetic though.

 

[zoobyshoe]

I'll give the manufacturer the benefit of the doubt and say that the material was chinced on the chromium. For steel to be considered a stainless steel a minimal amount of chromium as alloying element is 11%. Most likely they tried to get the bare bones minimum and were a little under, hence the rust. It's definitely not copper.

I thought 18-8 was the common material for most utensils. It's one of the 300 series austenitic stainless which is not magnetic. The 400 series is magnetic though.

I just tried out the 14 utensils (table knives, forks, table and tea spoons) in the drawer here and 12 out of the 14 stuck to the magnet, (this is a hodgepodge, I don't have a unified set) for whatever that's worth statistically. They're all rust and blemish free, and fairly old.

 

[mgb_phys]

Most are probably stainless steel,
The non-magnetic ones are either silver (common for teaspoons) or Nickel-silver (a copper /nickel alloy - nothing to do with silver) if they are old.

Copper is toxic in large enough doses (just about everything is!) but very expensive saucepans are also copper.
As someone sad the brown stains on the imported stuf is just rust.

Stainless steel isn't the best material to make blades out of - you used to be able to buy carbon/tool steel knife blades before someone decided that it wasn't safe because of the rust. Oddly at the same time everyone started taking iron and mineral supplements.

 

[zoobyshoe]

Most are probably stainless steel,
The non-magnetic ones are either silver (common for teaspoons) or Nickel-silver (a copper /nickel alloy - nothing to do with silver) if they are old.

No, I'm sure they are just the non-magnetic stainless alloy mentioned by Fred Garvin. By "fairly old" I mean ten years or so. Had they been chrome plated non-stainless, the plating would have deteriorated by now. I'm familiar with the particular look of silver utensils and these are clearly not that.

Stainless steel isn't the best material to make blades out of - you used to be able to buy carbon/tool steel knife blades before someone decided that it wasn't safe because of the rust. Oddly at the same time everyone started taking iron and mineral supplements.

Rust in wounds gives you tetanus, no?

 

[mgb_phys]

Rust in wounds gives you tetanus, no?

Nope - tetanus in wounds gives you tetanus! It's just that anny metal you cut yourself on in a farmyard is also liekly to be rusty.

There are 3 main types of stainless:
Austenitic, s highly corrosion resistant, tough and a bugger to machine but doesn't really sharpen well, we use it for making parts for marine enviroments. It's mostly non-magnetic ( except when we made a very sensitive magnetometer out of it).

Ferritic is the most common, it's pretty resistant to corrosion, cheap and easiest to machine. It's magentic and is used for cutelry but isn't hard enough for a really good edge.

Martensitic is the least corrosion resistant and brittle but is the hardest and holds an edge best, it is used for very high quality knife blades. It is magnetic. You can know do clever things to Martensitic to make it tougher and more corrosion resistant but that's expensive.

 

[zoobyshoe]

Nope - tetanus in wounds gives you tetanus! It's just that anny metal you cut yourself on in a farmyard is also liekly to be rusty.

Ah, I understand.

There are 3 main types of stainless:
Austenitic, s highly corrosion resistant, tough and a bugger to machine but doesn't really sharpen well, we use it for making parts for marine enviroments. It's mostly non-magnetic ( except when we made a very sensitive magnetometer out of it).

Ferritic is the most common, it's pretty resistant to corrosion, cheap and easiest to machine. It's magentic and is used for cutelry but isn't hard enough for a really good edge.

Martensitic is the least corrosion resistant and brittle but is the hardest and holds an edge best, it is used for very high quality knife blades. It is magnetic. You can know do clever things to Martensitic to make it tougher and more corrosion resistant but that's expensive.

Yes, I have a stainless folding knife that is probably the second kind because it doesn't take an edge for squat.

I used to be a lathe and mill operator and machined the first and second kinds occasionally, and I hated them both. Give me aluminum or cold-rolled.

 

[mgb_phys]

I used to be a lathe and mill operator and machined the first and second kinds occasionally, and I hated them both.

I'm an astronomer/optical engineer - we make a lot of stuff out of Invar, it's a 36% nickel ss with very low expansivity. But it's evil stuff to machine and eats drills and taps - I still have the scars.

 

[zoobyshoe]

I'm an astronomer/optical engineer - we make a lot of stuff out of Invar, it's a 36% nickel ss with very low expansivity. But it's evil stuff to machine and eats drills and taps - I still have the scars.

I had one run in with invar, and, yeah, I very much disliked it.

 

[edward]

If you're concerned about products from China, why the hell are you buying them?

Sure it said Stainless Steel, but you practical implied that you had doubts. But I guess you bought it because it was cheap. Money overrides everything.

I would say buy some that are from Canada or the US. That should be good.

Without spending an arm and a leg or two ,It is difficult to find anything for the kitchen that is not made in China. Sometimes it is just impossible at any price.

A lot of their spoons ect. are nickle plated steel. The nickle wears off fairly fast.

They are also cranking a lot of counterfeit name brand products.

 

[FredGarvin]

I just tried out the 14 utensils (table knives, forks, table and tea spoons) in the drawer here and 12 out of the 14 stuck to the magnet, (this is a hodgepodge, I don't have a unified set) for whatever that's worth statistically. They're all rust and blemish free, and fairly old.

I think you're going to have to sacrifice and donate your utensils so we can do cross section cuts and do a microscopy investigation. You can get 300 series to take a magnet but you have to do it on purpose. Do you live under really big electrical lines or have a distribution line running behind your utensil drawer?

 

[FredGarvin]

I'm an astronomer/optical engineer - we make a lot of stuff out of Invar, it's a 36% nickel ss with very low expansivity. But it's evil stuff to machine and eats drills and taps - I still have the scars.

Have you ever tried the free machining version of Invar?

 

[Evo]

Has anyone tried ceramic knives?

 

[mgb_phys]

Have you ever tried the free machining version of Invar?

Now they tell me

 

[zoobyshoe]

I think you're going to have to sacrifice and donate your utensils so we can do cross section cuts and do a microscopy investigation. You can get 300 series to take a magnet but you have to do it on purpose. Do you live under really big electrical lines or have a distribution line running behind your utensil drawer?

I don't know what to tell you, Fred. I just remembered I had a bunch of odd stainless utensils I'd bought at the swap meet to make into arrow heads. I just dug them out and tried them as well, and only one out of 33 would not attract the magnet. I think you are overestimating the percentage of utensils that are made from non-magnetic stainless.

 

[mgb_phys]

The only knives I can think of that would be made out of 300series stainless are dive knives.

 

[Oxygenne]

I have got a new set, made in Germany, Solinger.

 

[mgb_phys]

I have got a new set, made in Germany, Solinger.

I just tried my Solinger's they are very magnetic - as I said you wouldn't use 300 series unless anti-corrosion was more important than the blade quality.

Edit- Oh sorry you weren't saying your Solingers were non-magnetic, I misread the thread.

 

[Astronuc]

300 series SS are austenitic, while 400 series SS are ferritic.

304 and 316 are probably the most common 300 SS in use.

The kives in the Gunter Wilhem Professional Series Cutlery set are made with 440 SS. Other sites mention high carbon SS.

Interesting - many dive blades are 304, 420 or 440, but now Ti-alloys and Co-Cr alloys are available. Talonite™ is a Co - 30Cr alloy similar to Stellite.

Several steels and alloys are mentioned here - http://www.alphaknifesupply.com/bladesteel.htm

I would caution against Ni-plated cutlery. Ni is relatively mobile and will get into the food.


Tetanus is caused by a Gram-positive bacterium, Clostridium tetani. Several of this genus produce neuro-toxins, including Clostridium botulinum.


I've used ceramic knives of either silicon nitride or silicon carbide. They work well.

 

[Oxygenne]

I am so tired to worry about many things.
why do they sell toxic products and make us our living unsafe?

 

[mgb_phys]

Don't worry, lots of stuff is banned that our grandparents used everyday of their lives. If everything that is now banned was so harmful you wouldn't be here.
It's mostly to do with lawyers rather than science.
A bit of rust isn't going to hurt you.
Neither is a bit of dirt on your food.

Antibacterial soap is probably going to wipe out humanity but that's another problem.

 

[jmnew51]

Regardless of the type of steel the blade is made out of, there are 3 things I look for to evaluate the quality of the knife.

1. Bend the blade to assess its hardness. Tougher to bend, the harder the steel it is.

2. Blade geometry. The blade should taper from full thickness to a point, handle to tip.
and should have taper from top edge (full thickness) to cutting edge.

3. Knife construction. Should have heavy duty rivets afixxing the blade to the handle.

All of my "quality" cutlery is of this type of construction. I buy no other. Some that I have, has been passed down to me and is much older than I am and still going strong. And that's pretty old.

Jim

 

[Moonbear]

R
3. Knife construction. Should have heavy duty rivets afixxing the blade to the handle.

High quality chef's knives won't have visible rivets. The versions for household use still do, but the ones meant for professional chef's cannot have rivets anymore. I don't know when this was instituted, but the rivets apparently allow a place for bacteria to get inside and grow, so it's part of sanitation code now that knives used in restaurants have to have sealed handles. I'm sure they still have rivets, but they are entirely covered by the grip on the handle now.

 

[mgb_phys]

Commercial kitchens tend to use plastic handled knives that can go through dishwashers and they throw them away regularly rather than use the sort of knives you would buy to last a lifetime at home.

 

[Moonbear]

Commercial kitchens tend to use plastic handled knives that can go through dishwashers and they throw them away regularly rather than use the sort of knives you would buy to last a lifetime at home.

That depends on the type of restaurant. In your average chain restaurant where you have cooks, not chefs, yes, they're not going to get great knives for a bunch of high school kids chopping onions all day. But, in a better restaurant, where there's actually a professional chef, the chef will usually have his/her own set of knives and just has them sent out for sharpening every once in a while. The other prep cooks in the kitchen will still have the cheap, restaurant-owned knives. But, yes, they are all plastic-handled. They can't have wood handles, because those again can hold bacteria and can't be as easily disinfected.

 

[mgb_phys]

They can't have wood handles, because those again can hold bacteria and can't be as easily disinfected.

It's the same with wooden chopping boards.
It makes you wonder how we survived for 1000s of generations before we had all these safety standards!