Galvanised steel varroa floor mesh

[Eyeman]

Hi
Any food regulation concerns over using the above mesh as a cage in an honey extractor?
Thanks

 

[philipm]

Honey is acidic so if you leave it in the extractor it would react with the zinc in the galv.Why not use stainless steel mesh?

 

[B+.]

Hi
Any food regulation concerns over using the above mesh as a cage in an honey extractor?
Thanks

It has to be stainless steel or food grade plastic. Galvanised isnt't good enough

 

[Eyeman]

Thanks for that advice

 

[REDWOOD]

You often see them pop up in auctions and eBay and new Beekeeper's are always pray unfortunately but the gear mechanism is worth keeping for a DIY project


Sent from my iPad using Tapatalk Pro

 

[viridens]

Here goes...
I understand that Zinc is considered non toxic except at extremely high doses, in fact many folks take zinc supplements for the benefits.
Honey is not that acidic, and it is only in contact with the coating for a limited time. I bought an old galvanised extractor second hand, and used it for another 30 odd years. The zinc coating was still intact (i.e. no rusting) when I sold it on.

 

[mikepetty]

Here goes...
I understand that Zinc is considered non toxic except at extremely high doses, in fact many folks take zinc supplements for the benefits.
Honey is not that acidic, and it is only in contact with the coating for a limited time. I bought an old galvanised extractor second hand, and used it for another 30 odd years. The zinc coating was still intact (i.e. no rusting) when I sold it on.

The zinc is there to act as a protective coating over the underlying mild steel, which would otherwise corrode. The zinc is a sacrificial coating, corroding in preference to the iron in the steel. The protective action can persist even with only a partial coating of zinc remaining. So, when the conditions are such that the steel would otherwise corrode, the zinc corrodes a little instead, shedding zinc oxide. A small amount of zinc oxide in your diet is probably not going to do you any harm, but the point is that the honey would then contain an additive, albeit at trace levels. On the other hand, stainless steel normally produces a stable oxide layer and is immune to further corrosion over a wide range of conditions, which is why it is used so extensively in food production.

 

[viridens]

My understanding is that the sacrificial action is only relevant when the coating is scratched through to the base metal. Galvanised steel has a characteristic appearance, especially the thick hot-dipped layer on old extractors. It's pretty clear whether the coating is there or not. Anyhow, none of this concerns potential toxicity.

Has any research shown concerns about high zinc levels in honey from old extractors. or is it just a theoretical concern?
I also understand that there are health concerns about the cobalt and chromium leached from stainless steel utensils, and the phthalates from polythene containers too. Name your poison!

 

[Into the lions den]

Correct. Sacrificial protection is only in action if a galvanic cells occurs and electrical flow can take place.

Zinc is a bit like the more active aluminium. Oxidation with air forms a very tough skin that seals in the iron based metal inside and also the zinc coating itself, even if that skin is not visible to the naked eye. Honey also crystallises against the zinc and creates a further rather hard coating itself.

At a small scale level you will get away with a galvanised extractor, but as soon as you are large enough to attract the attention of the authorities to look at your processing conditions you have issues to contend with. Its not a total no no, but its a significant negative on your report card.

If you ever reach the scale where you get a client audit then its a goner, must be stainless steel and of specific grades too.

 

[mikepetty]

I also understand that there are health concerns about the cobalt and chromium leached from stainless steel utensils, and the phthalates from polythene containers too. Name your poison!

Contrary to popular belief, stainless steel is not immune to corrosion. I’ve seen some horrific examples of stainless corrosion, where you would think that the item was made from mild steel. However, compared to many other materials from which you could manufacture utensils that come into contact with food, stainless steel is usually stable and well behaved.

As others have said, if the zinc coating is complete then the zinc should be fairly stable too. However, in the event of the underlying steel being exposed through the likes of pinhole defects, scratches or abrasions then the zinc is intended to be shed in a sacrificial fashion to protect the steel. This would mean that it then gets into the honey.

 

[Little John]

Food regs can be crazy sometimes. Honey contains pollen, and pollen contains trace elements, i.e. metals. For example, in each kg of willow pollen, you'll find (typically):
80mg of Zinc; 325mg of Iron; 2000mg Magnesium; 3000mg Calcium; 8500mg Potassium - and maybe the odd touch of lead or aluminium too, if there happens to be any in the ground.

But - surprisingly - there's nothing on Tesco's rice packets about how much arsenic the rice contains ... and I reckon that's far more important than the odd mg or two of zinc accidently finding it's way into a jar of honey.

Stainless steel ? Yep - crevice corrosion can be a bitch, even with 316 (A4 grade).
LJ

 

[Eyeman]

The product being discussed is :National Varroa Galvanized Mesh
From:
http://www.simonthebeekeeper.co.uk/our-products/hives-parts/national-varroa-galvanized-mesh,-detail

Thanks

 

[masterBK]

I believe one of the problems of galvanished steel coming into contact with food is that it may contain small amounts of the toxic contaminant Cadmium which can leach out into the food

 

[Gilberdyke John]

The product being discussed is :National Varroa Galvanized Mesh
From:
http://www.simonthebeekeeper.co.uk/our-products/hives-parts/national-varroa-galvanized-mesh,-detail

Thanks

Well done for posting the reality check