Batch-to-Batch Consistency: Tips from the Pros

Brewer:  Robert Moline
Brewery:  Little Apple Brewing, Manhattan, Kan.
Years of experience:  Eight
House Beers: Wildcat Wheat, Custer’s Gold (American blond ale), Fort Riley Rye, Big Red Ale (amber), Prairie Pale Ale, Pony Express Porter, and Black Angus Stout

One of the best ways to guarantee consistent-tasting beer is by sampling your beer at every stage of the process. As soon as the wort is chilled, I pull off a sample to measure the gravity and then I taste and smell it. Next, I transfer the beer into my secondary for conditioning, have a sip of it, and measure the gravity. I prepare the beer for carbonation — we force carbonate — and have a sip of the beer and check the gravity. When the beer is ready to be put on the line to the customer, I check the gravity and have a sip of it.

Rigorous adherence to your formulas and procedures is very important as well. For example make sure you monitor the pH balance of the mash and sparge water, and check the lot numbers on your bags of grain. When you buy grain, there’s a range for each style. If I buy a bag of two-row malt, I know what range the color will be in.

But when you get the individual bag, it’s got a lot number on it. You can get a sheet from the manufacturer of the malt that lists the lot numbers and their colors. The color will fall within a range, but for each lot it could be a little higher or it could be a little lower. If the color doesn’t match our recipe exactly, we make adjustments up or down. Some manufacturers are very consistent from batch to batch. It helps to find a consistent product to begin with.

The major times we’ve had inconsistencies are when, by accident, we’ve ended up with the wrong bag of grain. We had one such episode recently. The grain bags have colored tags on the ends that specify what they are. For example a blue tag indicates this is a Munich malt with a specific lot number. You might have another bag that’s got a blue tag on it that says this is cara-Munich malt.

One of my assistant brewers thought he was picking up one bag of grain, and he was actually putting in another. As he put the empty bag of grain in the dumpster to get rid of it, he discovered he’d made the mistake and the beer would not have enough color. We had to come up with some plan quickly to get our color back up.

When you run into inconsistent ingredients, compensate for them. The easiest inconsistency to correct is your hop rate. Little variances in your alpha acids can affect flavor, especially in lighter beers.

If you’re used to using a hop, say Galena, that comes in at 10 percent alpha acid and the next batch of Galena you get in is 12.2 percent, then you have to make adjustments.

The easiest way to adjust is to break down into units what you’re used to using. If you’re used to using one pound of Galena with 10 percent alpha acids, you would multiply 16 (16 ounces) by 10, which is 160. So you’re looking at 160 units. The hop you have in now is 12.2 percent. You divide 160 by 12.2, which tells you that you need 13.1 ounces instead of 16 ounces of hops. It works in the opposite direction, too. If you are using 16 ounces of 10 percent alpha acid, still at 160 units, then all of a sudden your hops are down to 9.1 percent. You divide 9.1 into 160, and it tells you you’re going to need 17 or 18 ounces of hops.

As a homebrewer, ensuring consistent-tasting beer also starts with consistent products, including water. If your municipal area can’t supply you with consistent water, then you have to start analyzing your water and adjusting it. I’ve homebrewed in Manhattan, Kan.; Savannah, Ga.; and Tallahassee, Fla. As far as I’m concerned, you can make a good batch of beer as a homebrewer if the water tastes good.

Extracts should be consistent, too. Some liquid extract companies make outstanding products. Others make products that are adulterated with corn sugars and various other things. You need to experiment.

One of the most important principles in creating consistent beers is keeping good records on what you do for every batch. There’s nothing worse than making a jamming beer and realizing you don’t know what you did to make it that way. How much water did you strike in with? At what temperature? I’m talking all-grain, but good record keeping applies to extract brewers, too. At what temperature did you start? At what temperature did you pitch your yeast? What procedures did you use for reconstituting your yeast if you used dried yeast? What chemicals did you add to your water to acidify for sparging or mashing?

Following instructions is important for consistency, but the biggest mistake homebrewers make is following the instructions regarding the addition of dextrose that come with kits. The only thing dextrose should be used for is priming beer. Do that one simple thing and 99 percent of extract beers in this country would improve markedly. It would do so much toward persuading people’s friends to believe that this (homebrew) is a decent product.

The Tips

  • Taste your beer at each stage, starting from the time the wort is chilled to just before serving it.
  • Stick to brands and types of ingredients that are consistent, and always check them against the manufacturer’s description in case you need to adjust them.
  • Calculate adjustments to correct variances in alpha-acid rates and water.
  • Keep detailed records of each batch you make. Include such things as the temperature of water you strike in at and the procedure you use for making a starter culture of yeast.
Issue: January 1997