Understanding Malt Analysis Sheets -- How to Become Fluent in Malt Analysis Interpretation - Greg Noonan

"No two batches of malt are alike. The only sure way to predict their effect on your brew is to ask for and know how to read malt analysis sheets.

You are a serious grain brewer. Whether you brew professionally, as a hobby, or as an obsession, you take pride in your beer. You do everything you can do to reproduce each of your recipes accurately from brew to brew. Or do you?

Like most serious brewers, you probably adjust your hopping rates to reflect the alpha-acid content of each new lot of hops you purchase, but do you adjust your grains for changes in color, moisture, and extract potential? Do you know that a mere 2% increase in the moisture content of a new lot of malt accompanied by a matching drop in the extract potential can drag the density of a 12 °Plato (S.G. 1.048) wort down to 11.5 °P (S.G. 1.046) or increase the cost of malt 31/2%? Do you know that the color of dark-roasted malts commonly varies by 25-50 °L from lot to lot, or that one maltster's "dark crystal malt" may be 40-45 °L while another's is 80-90 °L and someone else's is 120-130 °L?

Even slight changes in malt specifications may have perceptible consequences, combinations of lot-to-lot variances in the color, moisture, and extract content of malts can seriously alter a recipe's results. Whether you brew at home or at work, the more you know about the malt you use, the better and more consistent your beer will be. You can enjoy that gain without suffering any pain -- understanding and using malt analysis sheets is neither difficult nor unpleasant." - Greg Noonan

You can read the rest of the article to learn malt analysis here