Expert: Spencer W Thomas - 3/7/2009

Question
I have been brewing for over 20 years. I recently bought a new 50 lb bag of 2 row pale malt. I mashed at 151 degrees F as usual, and the first two worts from this malt have a much lower SG than I usually get, around 1.048, instead of 1.055 to 1.060. Does malt vary in its sugar content, or change content if it gets old?

Answer
The yield of malt can certainly vary with growing conditions, etc. and with age.  Have you used this particular brand of malt before?  It may have been malted differently than what you are used to.  

If you're measuring the malt by weight, and it has a higher moisture content than you're used to, it will seem to have a lower yield.  It can pick up moisture (or lose it) to the environment if you don't store it in a moisture-proof container.

Another possibility is that the barley grains are a little smaller, and so aren't getting crushed as effectively in the mill, if you grind your own.  (If not, see above about moisture absorption, etc.)