When did canned Foods Become Safe to Eat?

[ralph124c]

I was reading about the doomed Franklin nArctic Expedition of 1845. This expedition was the first to feature canned foods …unfortunately, the canning processes of the time were primitive-there is reason to suspect that the foods were contaminated with botulism and lead (from the solder used to seal the lids). This continued to be a problem fopr some time (the Amewrican DeLong Arctic Expedition of the 1880’s) had similar problems-the crew regularly cracked teeth on solder balls presnt in the canned foods.
So, when did the sealing and canning processes evolve (to the point that canned foofds were safe to eat)?

[TriPolar]

From the Wikipedia page on Franklin’s Expedition (bolding mine):

…and three years’ worth of conventionally preserved or tinned preserved food supplies. Unfortunately, the latter was supplied from a cut-rate provisioner, Stephen Goldner, who was awarded the contract on 1 April 1845, just seven weeks before Franklin set sail. Goldner worked in haste on the order of 8,000 tins, which were later found to have lead soldering that was “thick and sloppily done, and dripped like melted candle wax down the inside surface”.

I think the technology was pretty safe from the beginning. People knew how to preserve in glass jars already. The lead was an issue as long as it was used, but when properly done should not have had much contact between the lead and the food. It would have been more of a problem for people who tried to subsist on canned goods. One early problem was in sealing the cans. In some methods the top was partially soldered on leaving a vent hole, then the food was cooked in the can and the vent prevented the can from exploding. After cooking while still hot the vent had to be sealed. This would have been a good way to put the food in direct contact with lead, and to allow contamination after the cooking process which should have halted the growth of toxic bacteria.

[ralph124c]

Thanks-yes, I did read a bout the villain (Goldner)-it also seems that soldering the lids was not a well-known craft then- Goldner’s tinsmiths used arsenic and borax as fluxes (to help the solder flow)!
For such a carefully planned expedition, the awarding of the provisioning contract (to a crook like Goldner) is unbelievable!

[Hail_Ants]

As an aside, the Franklin Expedition was doomed from the start, contaminated canned foodstuffs or not. In true 19[sup]th[/sup] century British stiff-upper-lip style they really thought they could just plow their way thru the northwest passage ice-flows, bending nature to their will via courage, fortitude & a little advanced technology. Even if the food had been okay they still would have gotten hopelessly stuck in the ice and not have had enough provisions to survive a trek on foot back to civilization.

James Burke’s great original Connections series spends some time on the origin of canned food (the French first used champagne bottles).

[ralph124c]

@Hail_Ants

As an aside, the Franklin Expedition was doomed from the start, contaminated canned foodstuffs or not. In true 19[sup]th[/sup] century British stiff-upper-lip style they really thought they could just plow their way thru the northwest passage ice-flows, bending nature to their will via courage, fortitude & a little advanced technology. Even if the food had been okay they still would have gotten hopelessly stuck in the ice and not have had enough provisions to survive a trek on foot back to civilization.

James Burke’s great original Connections series spends some time on the origin of canned food (the French first used champagne bottles).

This I find hard to understand-Franklin himself led an earlier expedition (by land) north from the Great Slave Lake-he knew that the Canadian Archipelago was likely to be icebound through much of tyhe year. Subsequent exploration (down the Fish River) confirmed the hostile nature of the country.
Other explorers warned Franklin about taking such a large party of emn into the Arctic-they knew how hard food was to come by. The canned food was immediately suspect-much of it was found putrified when the cans were opened. Franklin would have doen better to have had the men hunt seals and walrus-at least they would not have suffered from scurvey so soon.

[CalMeacham]

1810. That was the year Nicolas Appert won the prixze offered by the French military for preser ving food in glass bottles, after 15 years of experimentation:

Nicolas Appert

Appert didn’t know why it worked (Pasteur was far in the future), he only knew that it did. He used higher temperatures than Pasteur did, so his stuff should have been safe.
The same year, Peter Durand also patented the idea in Britain, but (as we learn from James Burke), since his family had canning connections, his patent also mentioned storing in cans besides glass bottles.

Problems arose when some manufacturers weren’t careful enough and didn’t completely seal the cans, or heat them high enough or long enough, or used solder that contaminated the food. But you can’t blame Appert for that.

[Isamu]

@ralph124c

This I find hard to understand-Franklin himself led an earlier expedition (by land) north from the Great Slave Lake-he knew that the Canadian Archipelago was likely to be icebound through much of tyhe year. Subsequent exploration (down the Fish River) confirmed the hostile nature of the country.
Other explorers warned Franklin about taking such a large party of emn into the Arctic-they knew how hard food was to come by. The canned food was immediately suspect-much of it was found putrified when the cans were opened. Franklin would have doen better to have had the men hunt seals and walrus-at least they would not have suffered from scurvey so soon.

I just finished reading The Terror by Dan Simmons which is a fictionalized account of the Franklin expedition, but based very much on detailed study of the factual expedition. If you want to understand how it might have been possible for things to go so badly, I recommend it. Bone-chilling reading.

[heathen_earthling]

Aren’t scientists now saying that canned foods were never safe to eat? At least some kinds like soup and tomatoes.

[Michael63129]

@heathen_earthling

Aren’t scientists now saying that canned foods were never safe to eat? At least some kinds like soup and tomatoes.

I presume that you are referring to the BPA scare (I wouldn’t worry unless you ate nothing but canned acidic foods, caution for infants is more warranted). In that case, you should be more concerned if you drink soda since the acidity of the food determines how much BPA leaches out. Also, since when did they stop using tin cans (actually steel with a thin tin coat) and instead coat them with plastic?

Also of note, back in 1968 they tested canned foodrecovered from the Steamboat Bertrand which sank in 1865, and was still safe to eat (if not so palatable) after over 100 years, so by 1865 they presumably had good enough canning practices (if not universally per previous posts).

[ralph124c]

@Michael63129

I presume that you are referring to the BPA scare (I wouldn’t worry unless you ate nothing but canned acidic foods, caution for infants is more warranted). In that case, you should be more concerned if you drink soda since the acidity of the food determines how much BPA leaches out. Also, since when did they stop using tin cans (actually steel with a thin tin coat) and instead coat them with plastic?

Also of note, back in 1968 they tested canned foodrecovered from the Steamboat Bertrand which sank in 1865, and was still safe to eat (if not so palatable) after over 100 years, so by 1865 they presumably had good enough canning practices (if not universally per previous posts).

Interesting link-thanks! I also read that some arctic explorers happened upon some 70 year old salted cod-when cooked (and rinsed of its salt) it was perfectly good