Stainless oxidation or rust in Hop Stainers

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Tyler Hurst

Well-Known Member
Mar 30, 2018
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Hi, so I just brewed a beer that I’ve brewed numerous times before. An all galaxy mango Milkshake NEIPA, but when I pulled my hop strainers out I noticed this red buildup that looks like rust or oxidation. My brew does have a slight “metallic” taste to it but I just put it in keg and it’s still only a week old (OG 1.062 FG 1.017). Pretty sure I’m just going to throw the strainer out but, does anyone know what this is?!?! I don’t want to throw out the beer too!!!


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Stainless steel can totally rust if it's contaminated with iron during manufacturing or sometime after and not passivated. If it looks like rust, it probably is.
looks like the screen is copper to me and the plating has come off... it should not be enough to hurt the beer and likely would have been neutralized by the yeast.
I highly doubt that the screen is plated copper. That would be really weird, but it would be simple enough to test with a file. Plus, you can see spot welds. If you look at the pics closely, you'll see that the orangish brown stuff is in the open area of the mesh.
Stainless can definitely rust but I agree that you can't really tell from pictures whether this is the case or the mesh has just captured some gunk.