[charliebrown]

I was given several cans of malt extract that had been stored in a fairly cool basement for aproximatly 30 years. the can are not rusty but are slightly bulged.  Are they usable?

[erockrph]

I was given several cans of malt extract that had been stored in a fairly cool basement for aproximatly 30 years. the can are not rusty but are slightly bulged.  Are they usable?

Bulging cans = botulism

Not only would I never use them, I'd double-bag them then throwing them away

[kramerog]

Bulging cans = botulism

Not only would I never use them, I'd double-bag them then throwing them away

IME Malt extract is likely to be too acidic for botulism, but the margin of safety is likely to be small.  Does anyone know what the pH of malt extract is?  Is it below 4.6?

Apparently, botulism would be detoxified by boiling.  https://www.fsai.ie/faqs/botulism.html

Having said all that, I would be concerned that the malt extract simply tastes bad.

[HoosierBrew]

Having said all that, I would be concerned that the malt extract simply tastes bad.

Yeah, for safety's sake I wouldn't use a bulging can of anything. But even if it were botulism free, it has to taste horrendous after that amount of time. In the past I've used cans of just expired LME that tasted stale and off.

[beersk]

I was given several cans of malt extract that had been stored in a fairly cool basement for aproximatly 30 years. the can are not rusty but are slightly bulged.  Are they usable?

Bulging cans = botulism

Not only would I never use them, I'd double-bag them then throwing them away

Really? Man, botulism to me is akin to yelling the word "bomb" in an airport. I wouldn't even bother with these cans of extract if there were even the smallest chance that botulism might've happened. Run away from them as fast as you can.

[Joe Sr.]

My recollection from previous discussions of this is that nothing can grow in the extract as the brix is too high.

No one gets worried about old honey, right?  Pretty much the same thing here.

But, I am not a doctor or a scientist, so take that into account.

Regardless, I doubt it would taste good if you made beer with this extract.  And 30 years is pretty extreme.

[hopfenundmalz]

Those are not good. Malt extract will oxidize and browning reactions make it turn dark. Our club got some that had passed the best by date. They were Pilsen malt extract. Guess what, the extract was brown in color and tasted stale. Some made stale tasting beer from those. I made starters, and decanted off before the pitch.

[charliebrown]

I was given several cans of malt extract that had been stored in a fairly cool basement for aproximatly 30 years. the can are not rusty but are slightly bulged.  Are they usable?

thanks for all the feedback I don't think I'll try using them. again thanks