Improving Your Efficiency

People ask me all the time how to increase their mash efficiency. (For more on what efficiency is check out last weeks blog post). There are several factors that affect efficiency, they all work in conjunction with each other. Let's start with your mash tun. Using a cooler is very efficient because it allows you to maintain temperature throughout the mash. This will keep those enzymes working. The type of false bottom you use in your tun is also important. If you are using a kettle screen you are better off doing a batch sparge instead of a continuous sparge. Water likes to find it's level and with a kettle screen your water will channel towards the screen. If you are continuously sparging this channeling can cause a lot of your grain to not get rinsed leading to lower efficiency. When you batch sparge channeling is not a problem. Continuous sparging is more efficient because sugar in suspension stays in suspension, but you don't want channeling. That is why a perforated false bottom is best for continuous sparging, the water won't channel to one place and you will have a more efficient sparge. But even before you mash there are ways to increase your efficiency. Freshness of your grain is very important. Fresh grain will give you better flavor and better enzymatic conversion. The percentage of diastatic (enzymatic) malt to non-diastatic malt is also important, as is the ˚Lintner of your malts. ˚Lintner is the measure of enzyme power in your malt (not to be confused with ˚Lovibond, which is the measure of grain color). A malt needs at least 35˚Lintner in order to convert its starches to sugar. If you are using a large amount of non diastatic malts in your grist, make sure you have enough ˚Lintner to cover the entire grist .The crush of your grain is also very important. We want as fine a crush as possible so the water can hydrate the starch, and the enzymes can get in there and do their job, but not too fine because we need grain hulls for the lauter/sparge or else the whole thing will get stuck. People who brew in a bag will double crush their grains to increase efficiency because they don't have to worry so much about sparging, but there is a chance of more tannin extraction from the hull if it is crushed too fine. So we have a good mash tun and an excellent fresh crush, what's next? Why, water of course! The malt enzymes need the right water to grain ratio, the right temperature and the right pH to work at their optimal efficiency. The water to grain ratio should be between 1.25-2.5 quarts of water per pound. Brew in a bag is usually a little higher than that since it is a no sparge or mild sparge method. With a mash tun I find 1.3 quarts per pound to beer optimal. Temperature of the mash will depend on what enzymes you are trying to activate. For our saccharification enzymes we want between 140 to 150˚F for beta amylase and 150 to 160˚F for Alpha Amylase enzymes. If you are already doing all grain you should know the math or use calculators to determine your strike water temperature, so I won't go into it. But pH is something that many brewers do not bother with. By adjusting your pH in the mash you can increase your efficiency 5 to 10%. Without getting too deep into water chemistry, most base malts when mashed with distilled water will have a pH of 5.7 to 5.8, from the natural acidifying action of the malt. But beta amylase likes a ph of 5 to 5.6 and alpha amylase like it a little higher, between 5.3 and 5.8. (Remember, ph readings are always assumed to be at room temperature). So a good general overall mash pH is 5.5. New York City water is very soft and does not have enough minerals to lower our mash pH. This is where calcium additions come in. Calcium sulfate (gypsum) and Calcium Chloride will add calcium to the mash that will react with malt phytase and reduce the pH of the mash. Or you can use some acidulated malt (one or two ounces for a five gallon grist should do it) to lower your pH and increase your efficiency. This is obviously a much larger subject but worth looking into as water adjustment can really help with efficiency and overall beer flavor. For more information check out John Palmers book Water. Also check out his water adjustment spreadsheet available on the LaMotte site. The amount of time you mash also affects your efficiency. Although 60 minutes should be enough time to convert all of your starches, do a conversion efficiency reading to make sure you are at 100% before you sparge. If not mash a little longer until everything is converted. As I said before all of this works in harmony. If you're not getting the efficiency you want, go through these suggestions and see what you might be able to improve. Or drop by the store and ask one of us, we are always happy to help you get the best wort possible. Keep it efficient! John