Is it safe to use old dried malt extract?

Question

I have some dried malt extract that’s been sitting in the basement for mumble years. It’s turned into a brick. Is it safe to use this in brewing a new batch of beer?

I realize that it may have picked up flavors from the basement, but is it otherwise safe to use? Elsewhere I’ve seen references to DME having a shelf life of a year. Why is that? DME is nearly all sugar, isn’t it? Elsewhere I read that DME might have 4–5% protein and a tiny amount of fat. Can anything happen with these to affect the flavor or safety of the beer made from it?

Answer 1

I have tried this myself, using DME that had been stored cool, dry and in airtight barrier packaging, but was three years past its BBE date. The beer tasted weird, but I feel fine. However, it is possible for molds to get into old DME which could potentially be harmful since some molds are toxic, so it depends on what has managed to get into it while it was sitting in a dusty and musty basement. If the packaging is intact you should be fine. DME is hygroscopic and may draw in moisture from the air through the plastic of the packaging (unless it is barrier packaging) but molds etc. won't pass through it. So even if it has turned into a brick you should be fine at long as the packaging is 100% intact.

Old malt extract may acquire some weird flavors when it gets too old. It depends on the quality of the original product, its age and the conditions under which it was stored.

Answer 2

Since it should always be boiled, I don't see why it could not be used. Those bits of protein and fat might decompose, but these will not form harmful compounds.

Take your time to dissolve in hot, but not boiling water.

To improve the taste, you could steep some crushed light fresh caramel/crystal malt and add it to the obtained wort.