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Comment by rkhassen9

2 days ago

"Generally I relied on canned goods to supply the bulk of my meals. Each can was protected in double Ziplock bags to prevent rusting. Pinhole leaks in cans caused by rust and corrosion can be lethal to the unsuspecting mariner."

Is a pinhole leak on a can really that dangerous on a 24 day trip. I get ocean air...but wow. That is something I would have underestimated for sure.

wondering if someone in the know can weigh in? is this over cautious or like yeah, good idea?

I recall reading Kay Cottee's account of her solo unassisted circumnavigation in 1988. She was the first woman to do so.

Part of her preparation was removing the labels from all tinned food, and then re-writing what was in the can with a permanent marker on the lid, before fully immersing each can in laquer. Presumably this was done to help deal with corrosion problems.

I can't think of a reason it'd be any more dangerous than if the same food was sitting on your counter for the same time period. But some people won't eat cold pizza that sat out overnight either.

When we can food, sometimes there's a jar that doesn't seal. We just put it in the fridge and use it in the next few days. It'll keep at least as long as if it hadn't been canned.

Having said all that: if I went to open a can of food and saw that it had a leak, I wouldn't eat it, because how could I be sure that it wasn't leaking when I packed it 24 hours ago? A visible leak now might have been too small to see then, so who knows how long it's really been leaking.

  • A pinhole means low oxygen + outside contact which means botulism, which only thrives in almost sealed environments. Botulism toxins kill. Moreso than many other ways your food can spoil open to the air.

  • Rust develops much faster on a boat at sea. A breach from rust can affect a can with enough botulism toxin to have bad effects within 3-4 days. Most cans probably have a plastic liner though but I'm not sure how much of a safeguard it is.

I used to live and work on tall ships.

We never had this issue, but we also likely had better storage conditions in that there was precious little chance of actual seawater reaching our food cans. Cans would sometimes rust on the rim, but I don't think I ever saw a can rust all the way through, despite some of them being likely years old.

This seems like overkill unless you are very convinced that your cans will come in contact with seawater.

  • Tiny boat, probably got considerable water onboard.

    • With admittedly close to zero sailing experience, I would think that if your boat (no matter how big or "tiny") is getting "considerable" water onboard, you have bigger problems than your canned food.

      It doesn't make sense to me either that the size of the vessel has much to do with how watertight it is.

      But like I said, I don't have much experience in this!

      1 reply →

  • >This seems like overkill unless you are very convinced that your cans will come in contact with seawater.

    It seems like a really minor effort layer of protection with almost 0 overhead to protect a person against death. Getting botulism food poisoning at sea by yourself in a tiny boat could very well be a death sentence. Especially if a substantial portion of your food was compromised.

    $20 at costco for bags and an hour bagging all of your cans before your trip is hardly overkill.

    • I guess a more accurate way to say it is that I never heard of doing anything like that in my career on sailboats.

      Its cheap and relatively low effort, but I just don't see the benefit. Modern cans typically already have a plastic coating on the inside that will take care of things getting in through any pinholes, and to preserve flavor.

      I spent close to a decade as a professional sailboat captain, including on long offshore passages. I never saw a single can of suspect food, and it wasn't something that is ever talked about. Even in survival kits you would see canned goods that weren't wrapped in plastic.

      Really, if you are in the business of minimizing risk, you don't undertake an open ocean voyage in a 19 ft. sailboat.

      4 replies →

Bacteria is everywhere.

  • Most is not particularly harmful. Some is really bad and it trives in conditions that are rare (probably because we encounter the common ones enough that not being resistant is an evolutionary dead end). rare dosen't mean never seen though.

  • But double bagging each can for a trip seemed excessive.

    Maybe he’s concerned about cans banging around on a boat.

    Thanks for your thoughts!