Zinc Bolt in beer

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Cyclometh

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Hey folks, some insight requested.

I have a batch of pumpkin ale based on a Scotch Ale recipe going. I put it in to ferment on November 1. When I did so, the drilled stopper ended up deep in the neck of the carboy. When I needed to remove it to put on a blowoff tube, I used a small toggle bolt to snake through the drillled stopper and yank it out. It worked, the second time.

The first time, the wings on the toggle bolt snapped off and dropped into the beer. They were sterilized, so I was annoyed but not worried- just grabbed another one, sterilized it and extracted the plug.

A few days later (today) I was browsing another topic and found some discussion of not using zinc-coated steel, which these were. So I went on home at lunch and racked the beer to a secondary (which I'd been thinking of doing soon anyway) and found the pieces of the bolt in the bottom of the yeast cake, totally stripped of their coating. They were dropped in on the second day of fermentation, after the activity had peaked (but I didn't know that at the time).

The beer is at 1.012, and I tasted it- It was bitter, but there was no metallic flavor to it. The bitterness wasn't from hops either, but definitely wasn't a metallic tang; it was more like a raw taste; astringent. I think that's because the beer is so young, not from the zinc. Other than that, it tasted great and damn if it's not high ABV. :rockin:

The parts were pretty small; the total surface area of the pieces would be about equivalent to a 3/8" inside diameter steel washer. The total volume of liquid plus sediment was about 5.5 gallons, of which about 5 or so transferred via racking to secondary. There was a hell of a yeast cake at the bottom, a good inch and a half thick.

So, my question to the HBT peeps: Is the beer safe to drink once I bottle and condition it for a few more weeks? Will the zinc present any type of health hazard? I'm inclined at this point to not worry overmuch, but I wanted to hear from others who may have deeper knowledge, or experience.

Lesson learned, though- no zinc coatings!
 
Well,I would think that once the beer clears,carbonates,& conditions in the bottles/keg it can show up then. Small off flavors can hide till the beer ages a little.
 
I figure I'm running the risk of some bad flavors; I'm OK with that. I'm more concerned about safety. However, I looked into it more and it seems that the recommended amount of zinc daily is about 9-11 mg. The parts in the wort weighed less than 100mg, of which the vast majority was steel.

My rough estimate is that as little as 4 and as much as 10 mg of zinc ended up in the beer. I don't think that's going to be a major problem.
 
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