Article

Adjuncts Explained

It is fashionable among homebrewers to dismiss adjuncts as unworthy ingredients in beer. They often cite the German “Reinheitsgebot,” a purity law promulgated in 1516 that allowed only the use of water, malted barley and hops. Yet adjuncts are viewed differently around the world. Köln and Brussels are both world-famous brewing centers. Although located within 165 miles of each other, the brewing philosophies of these cities are light years apart. While German brewers were restricted for centuries by the Reinheitsgebot, Belgian brewers have long obtained fermentables from a wide variety of sources. In fact, adjuncts play a role in some of the world’s great beer styles.

Not all brewers define adjuncts in the same way. The most common definition is any source of starch that is not malted, but in this article we also will discuss “adjunct” ingredients like malted wheat and rye.

The use of adjuncts has been a popular topic of discussion over the years. “The Practical Brewer,” a classic textbook published by the Master Brewers Association of the Americas, states that “adjunct use results in beers of lighter color with a less satiating, snappier taste, greater brilliancy, enhanced physical stability and superior chill-proof qualities.” In the “Handbook of Brewing,” a chapter on adjuncts written by Graham Stewart of Heriot-Watt University adds this: “Corn gives a fuller flavor than wheat, which imparts a certain dryness. Barley gives a strong, harsher flavor. Both wheat and barley adjuncts can considerably improve head retention. Rice will also give a very characteristic flavor to beer.” Adjuncts not only lend different flavors to homebrews but also improve mouthfeel, head retention and clarity.

Adjuncts can be divided into two broad groups: kettle adjuncts and mashable adjuncts. Kettle adjuncts, like honey or candi sugar, contain fermentable sugar and are added to the kettle in the boil. Mashable adjuncts contain starch. This starch needs to be converted to sugar before it can be used by brewer’s yeast. These starchy adjuncts must be mashed, which means that enzymes degrade the starch to fermentable and unfermentable sugars and dextrins.

Most adjuncts — including rice, corn and kettle sugars — contain very little protein and they are reluctant to yield the protein they do have during mashing. So they also can be considered in terms of their ability to dilute the protein in a wort made from low-protein adjuncts and malted barley. All the protein in this wort comes from the barley, so adding a source of extract that carries no protein effectively dilutes the total protein in the wort. Protein in barley can cause haze. People generally prefer beers to be crystal clear and they expect that clarity to last for months. So by diluting protein with the proper amount of adjuncts, brewers can increase clarity and stave off the onset of chill haze.

When brewing with low-protein adjuncts, brewers must take care not to dilute the malt’s soluble nitrogen too much, or a wort may be produced that lacks enough amino acids. Yeast need simple soluble amino acids in order to grow. Nutrient deficiency can result in poor yeast performance and off-flavors. Most of the precursors to stale flavors in beer are derived from malted barley, so diluting the malt with a non-malt adjunct may reduce stale flavors.

Before the enzymes in the mash can break down the starch in the cereal, whether it’s corn or malted barley, the starch must be gelatinized. Because starch is a mixture of chemical compounds, before it forms a solution it forms a thick gel. The way the starch is packed into the endosperm affects the temperature at which it will form gel.

Some mashable adjuncts have low gelatinization temperatures and some have high gelatinization temperatures. This has a tremendous effect on how we use the adjuncts. The starch in unmalted barley will gelatinize at 140° to 143.5° F, with the starch in malt slightly higher at 147° to 152.5° F. The starch in wheat gelatinizes at 125.5° to 147° F, so when it is added to a malt mash it will gelatinize along with the malt starch. Both corn (at 143.5° to 165° F) and rice (at 142° to 172° F) have high gelatinization temperatures and require a separate heat treatment. Usually corn and rice are mashed separately, along with some malted barley (10 percent), and then boiled in a cereal cooker. They are held for a while as they are heated at a temperature of 158° F to allow malt enzymes to act on the starch and make it less viscous. The cereal mash is then added back to the main malt mash at a controlled rate to raise the temperature of the main mash to its various enzyme rests.

Mashable Adjuncts

Mashable adjuncts can be further divided into two groups, depending on whether the adjunct has the enzymes it needs to break down starch. Malted adjuncts, like malted wheat or malted rye, contain enzymes; other adjuncts, like corn or rice, lack them. They rely on the fact that malted barley has a surplus of enzymes, enough to convert the starch of both barley and adjunct.

The degree to which we can use unmalted adjuncts without experiencing difficulties depends on the base malt and the mashing regime. With a multiple-temperature mash, American six-row malts can tolerate up to 50 percent adjunct, and American two-row can tolerate up to 30 percent. British malt used in a single-infusion mash can tolerate up to 20 percent.

Flaked and torrified grains are not malted and do not contain the necessary enzymes to convert starch. Flaked grains are made by treating the cereal with steam and then crushing the grain between hot rollers. Common brewing grains in flaked form are oats, rye, corn and rice. Torrified grains are made by heating grains to a temperature of 500 degrees until they “pop,” like puffed wheat.

Rice

Rice is the first mashable adjunct that comes to mind, perhaps due to the fact that the world’s biggest-selling beer, Budweiser, proudly advertises its use on the label. Rice is a staple food for over 50 percent of the world’s population and comes in many aromatic and non-aromatic varieties. The non-aromatic varieties are used for brewing. The brown rice harvested from the paddy fields is milled to remove the bran and germ and the whole kernels are sold for domestic consumption. The kernels that get broken are sold at a lower price to brewers.

Rice has a high gelatinization temperature and must be boiled prior to use. Some brewers boil the rice under pressure to increase the temperature. Rice has the highest starch content of all the cereal adjuncts and may yield as much as 90 percent extract efficiency.

Corn

Corn is used by brewers in two main forms: milled grits or flakes. Corn grits are the most widely used adjunct by commercial brewers in the United States and are an important adjunct in Great Britain, where it is called maize. Grits are produced from yellow and white corn (mostly yellow), which is milled to remove the bran and germ. Grits are widely available and require a cereal cooker and separate boiling step similar to brewing with rice. Corn flakes resemble the breakfast cereal and can be used directly in the mash. They can be milled with the malt or crushed by hand and mixed with the grain. Though a box of Kellogg’s contains additives that are best left out of homebrew, you can find bulk corn flakes at health-food stores or homebrew shops that are additive-free and sometimes sweetened with malt extract.

Corn and rice are both used in the production of American pilsners. In some of these lagers, the cereal may represent up to 50% percent of the total extract. If you are trying to brew a light-colored beer, using corn or rice will allow you to brew a beer that is lighter in flavor and color than an all-barley malt version of that beer. Typically, brewers use up to 30 percent of these adjuncts.

Unmalted barley

Unmalted barley is used as an adjunct in several major breweries around the world. It is significantly cheaper than malted barley and can be blended at up to 50 percent, provided the enzyme levels are high and an extensive temperature-profile mashing schedule is used. It is difficult to mill as the kernels are extremely hard. It contributes a large amount of beta glucan to the wort, because this troublesome compound is reduced during malting. Beta glucan can improve foam stability, but in excess it impedes lautering.

Sorghum

Sorghum, also called millet, is the fifth most popular cereal crop in the world. It is used as the base grain in several native African fermented beverages and is used by brewers in Africa and Mexico as part of the grist in their lager-style beers. Sorghum was used in American breweries in the 1940s when traditional ingredients were scarce due to the war, but quality problems led to it being abandoned.

Unmalted wheat

Unmalted wheat is used in some recipes that require its specific attributes; namely, the raw grain flavor and cloudy appearance associated with Belgian white beer. It requires a multiple-temperature mashing regime with temperature rests at 120° F (beta glucan rest), 150° F (beta amylase rest) and 170° F (alpha amylase rest). The gelatinization temperature is lower than barley so it can be mixed into the mash directly.

Oats

Oats are low in starch, high in oil and protein and extremely high in beta glucans. As a result, they are not used as a major substitute for malt in the grist. However, they add a smoothness and increased mouthfeel to beers and have become popular as an additive to stouts. One of my favorite brewing stories involves a famous English brewer who was planning an oatmeal stout. He ordered the finest oats for his masterpiece only to find that, when they were delivered, an uninformed gate guard had directed the delivery vehicle to the brewery’s stables.

Rye

Rye is another grain that is used for its flavor, rather than as a malt replacement. It has a strong distinctive bite but is difficult to lauter, so extract recovery is difficult and slow. Rye is known to impart an orange tinge and a spicy character to beer.

Brewing with malted grains

Wheat, rye and oats are all available as malted grains. These adjuncts should be used for specific flavor or quality contributions.

Malted wheat may be 50 to 75 percent of the grist in a German wheat beer. Since wheat has no husk, brewing with malted wheat can be tough. Many brewers use rice hulls to establish a good filter bed in the mash. Rice hulls replicate the role of barley husk in the lautering stage and hence aid wort seperation. Commercial brewers are unlikely to need rice hulls even with malted wheat concentrations as high as 50%, since lauter tuns are well designed for effective wort seperation. On homebrew equipment, a handful of rice hulls will go a long way to improving matters. Wheat adds a tangy character and improves head formation and retention.

Malted rye is used in rye whisky and can be used to make distinctive beers. Rye malt makes up to 10 percent of the grain bill in rye beers. Rye cannot be used in larger quantities because it contributes to stuck mashes.

Some stouts are brewed with up to 25 percent malted oats. Oats, with their high oil content, add a creaminess to beer.

To use malted adjuncts, all-grain brewers simply crush the grains along with the malted barley and add it to the mash. Extract brewers must do a partial mash. Malted adjuncts contain amylase enzymes, so they can convert their own starch into sugars without the addition of malted barley to the partial mash.

To do a partial mash, the grain must be crushed and placed in a nylon grain bag. Steep the grain in water at a temperature of 150° to 158° F for 30 minutes. Make sure you have enough water to completely submerge the grains. During this time, the starch will be solubilized and the amylase enzymes will chop the starch molecules into sugar molecules. After mashing for 30 minutes, remove the grain bag with a large kitchen strainer. Rinse the grains with a few cups of 168° F water to extract sugars still clinging to the grains. Next heat the mash water to boiling, add your malt extract and finish brewing as you normally do.

Brewing with flaked grains

All-grain brewers can simply add flaked grains to their mash. Although flaked grains have no amylase enzymes, excess enzymes from the barley can degrade the starch. When using over 20 percent flaked corn or rice, it is preferable to use six-row malt for the remainder of the grain bill. Six-row malt has more enzymes than two-row  and is better able to convert the extra starch load. And the low protein of the adjunct helps dilute the extra protein from the 6-row malt.

As with malted grains, extract brewers must perform a partial mash if they wish to use flaked grains. When mashing these flaked grains, the brewer must also add barley malt to supply enzymes. A 1:1 mixture of flaked grains and six-row barley malt is usually sufficient. Crush the barley malt and place it in a grain bag with the flaked grain. The flaked grain does not need to be crushed but it helps to break it up. Once the grains are mixed, steep the grain in 150° to 158° F water for 30 minutes, rinse the grains and proceed.

Kettle adjuncts

Many adjuncts already contain soluble sugar and do not need to be mashed. These adjuncts are added to the wort during the boil and are called kettle adjuncts. This group includes a wide variety of sugars and syrups. Syrups may be produced directly from sugar beet or cane, or extracted from corn or wheat starch. They may be pure glucose (dextrose) or a mixture of glucose and fructose (invert sugar). Or they may contain maltose, maltotriose and large dextrins. Kettle adjuncts are used in small amounts, typically less than 10 percent of the grain bill, although like cereal adjuncts they can be used in much higher amounts.

An excellent lager produced in Asia called Singha contains a lot of brown sugar. In the UK, I once used a completely non-fermentable dextrin syrup as a solvent to add a fresh ginger character to an alcoholic ginger beer. Some kettle adjuncts — like honey and molasses —  add flavor to beer.

Most types of honey have a delicate flavor, so adding small amounts — less than 5 percent of the fermentables — will have little effect. If you want a big honey flavor in your homebrew, you can add up to 30 percent honey. If you use over 15 percent, however, add some yeast nutrients. If you are brewing with molasses or maple sugar for the first time, go easy. Both are available in a variety of forms that are more or less flavorful.

Other adjuncts mainly just boost the strength of the beer. Cane sugar, corn sugar, Belgian candi sugar, corn syrup and rice syrup add little flavor when used in small quantities (around 10%). They boost the amount of fermentable sugar in the wort without adding protein and color to the beer. Over about 10 percent, these sugars can lend a solvent-like, highly alcoholic taste. Over 30 percent and yeast nutrition can suffer, especially in beers made from malt extract.

When I brewed in England I would often use sugar to increase the original gravity of the wort, including a couple of medal-winning barleywines that included 25% sucrose. For my lighter beers, I used an invert sugar, as a straight replacement for malt, that was delivered in solid blocks of paste. Invert sugar is produced when a more complex sugar, such as sucrose, is treated with acid or an enzyme to split it into its component molecules. This changes the rotation of light when viewed through a special instrument and the change is referred to as an inversion.

Brewing with kettle adjuncts

Handling kettle adjuncts is simple. Once the wort has come to a boil, shut off the heat and stir the adjunct into the wort. If you do not shut off the heat, the thick, sugary solution can fall to the bottom of the kettle and scorch. When the adjunct is dissolved, resume the boil. You can add kettle adjuncts at any time during the boil, but they should be boiled long enough to ensure the wort is sterile. One factor to consider is that increasing wort gravity reduces the efficiency of hop utilization. To improve hop efficiency it may be wiser to add syrups near the end of the boil. I usually add kettle adjuncts for the final 15 minutes of the boil.

Adjunct Recipe File

Condoleeza Lager
(5 gallons, extract with rice syrup)
OG = 1.045 FG = 1.010 IBU = 11

4 lbs. dried malt extract
(light, unhopped)
16 oz. rice syrup
3.52 AAU Hallertau hops
(0.88 oz. hops at 4% alpha acid)
1 tsp. yeast nutrient
Wyeast 2007 or White Labs WLP840

Bring 4 gal. of water to a boil. Turn off heat and add extract and rice syrup. Stir to dissolve, then boil wort for 1 hour. Add hops at beginning of boil. Add yeast nutrient for final 15 min. Cool and transfer wort to fermenter. Aerate wort and pitch two-liter yeast starter. Ferment 1 week at 52° F. Transfer to secondary and  lager for 90 days. Keg or prime and bottle.

Older but Wiser Rice Beer
(5 gallons, all-grain with rice)
OG = 1.044 FG = 1.008 IBU = 11

6.5 lbs. pale malt (6-row)
1.5 lbs. rice
3 AAU Hallertau hops
(0.75 oz. hops at 4% alpha acid)
Wyeast 2007 or White Labs WLP840

Mix rice with 1/4 lb. crushed pale malt and 1 gal. water and hold mini-mash at 158° F for 15 min. Boil mini-mash for 30 to 45 min. Add 2.25 gal. water at 110° F to the mini-mash, along with all remaining malt, to bring temperature to 122° F. Hold mash for 15 min., then raise temperature to 150° F for an hour. Heat to 158° F for 5 min., then mash out to 168° F. Recirculate wort for 20 min., then collect 4.5 gal. of wort. Sparge water should be at 168° F. Add 1.5 gal. of water to wort to make 6 gal. Boil wort vigorously for 1 hour. Add hops when boiling starts. Cool wort. Siphon to fermenter. Aerate wort and pitch one-gallon yeast starter. Ferment for 7 days at 52° F. Rack to secondary fermenter and lager beer for 90 days. Keg or prime and bottle.

RMS Corn-Fed Lager
(5 gallons, extract with corn syrup)
OG = 1.045 FG = 1.010 IBU = 13

3.5 lbs. dried malt extract
(light, unhopped)
24 oz. corn syrup (no preservatives)
4.24 AAU Hallertau hops
(1.06 oz. hops at 4% alpha acid)
1 tsp. yeast nutrient
Wyeast 2007 or White Labs WLP840

Boil 4 gallons of water. Turn off the heat, then add the malt extract and corn syrup. Stir thoroughly. Boil wort for 1 hour, adding hops as soon as the wort begins to boil. Add yeast nutrient for last 15 minutes. Cool wort. Transfer wort to fermenter and aerate. Pitch two-liter yeast starter. Top fermenter up to 5 gallons with boiled and cooled water. Ferment for 1 week at 52° F. Transfer beer to secondary fermenter and lager for 90 days. Keg or prime and bottle.

Iowa City Maize Lager
(5 gallons, all-grain with flaked maize)
OG = 1.044 FG = 1.008 IBU = 13

6 lbs. pale malt (6-row)
2 lbs. flaked maize (corn)
3.52 AAU Hallertau hops
(0.88 oz. hops at 4% alpha acid)
Wyeast 2007 or White Labs WLP840

Mash malt and flaked maize using a step mash. Mash for 15 minutes at 122° F followed by 45 minutes at 152° F. Mash out by raising the mash temperature to 168° F. Recirculate wort for 20 mins. Run-off and sparge wort; sparge water should 170° F. Collect 4.5 gallons of wort. Add 1.5 gallons of water, making 6 gallons of wort. Boil wort vigorously for 1 hour. Add hops as soon as wort begins boiling. After boiling, cool wort, then siphon to primary fermenter. Aerate wort thoroughly and pitch sediment from one-gallon yeast starter. Ferment for 7 days at 52° F, then rack to secondary. Lager beer for 90 days, then keg or prime and bottle.

Big Daddy Dry Stout
(5 gallons, all-grain and flaked barley)
OG = 1.040 FG = 1.008 IBU = 45

5 lbs. pale malt (2-row)
1.5 lbs. flaked barley
0.7 lb. roasted barley
12 AAU Fuggle hops
(2.4 oz. hops at 5% alpha acid)
Wyeast 1968 or White Labs WLP002

Combine pale malt with roasted barley and flaked barley and mash at 150° F for an hour. Heat to 158° F for 5 minutes. Recirculate wort for 20 minutes and collect 4 gallons of wort. Sparge water should be at 168° F. Add 2 gallons of water to make 6 gallons. Boil for 1 hour. Add hops immediately after boiling starts. Cool wort.  Siphon to primary fermenter. Aerate wort and pitch yeast from one-gallon starter. Ferment for 7 days at 68° F. Rack to secondary and ferment for an additional 7 days.
Partial-mash option: Replace 2-row pale malt with 2 lbs. 6-row pale malt and 2 lbs. dried malt extract (light, unhopped). Make a partial mash of the malted, flaked and roasted barley. Hold partial mash at 150° F for 30 minutes. Rinse the grains with 1 qt. of water at 170° F, then bring wort to a boil. Add extract when boil  begins.

Forgotten Carboy Lambic
(5 gallons, all-grain and raw wheat)
OG = 1.055 FG = 1.005 IBU = almost 0

6 lbs. pale malt (2-row)
3 lbs. wheat
3.08 AAU Tettnang hops (aged 3 years)
(0.88 oz. hops at 3.5% alpha acid)
Wyeast 3273 (no starter)

Make mini-mash of wheat and 1/3 lb. pale malt. Hold at 158° F for 15 minutes, then boil for 30–60 minutes. Combine remaining pale malt with wheat mini-mash. Step mash all grains at 120° F for 15 minutes followed by 150° F for 45 minutes. Heat mash to 168°F and hold for 5 minutes. Recirculate wort for 20 min. and collect 5 gallons. Sparge water should be at 168° F. Add 1 gallon of water to make 6 gallons. Boil wort  for 1 hour. Add hops immediately after boiling starts. Hops should be aged. Cool wort.  Siphon to primary fermenter and pitch yeast (no starter). Ferment for 7 days at 68°F.  Rack to secondary and ferment for 3 months to 3 years. Package beer and serve.

The Kurgan’s Scottish Ale
(5 gallons, extract with brown sugar)
OG = 1.060 FG = 1.020 IBU = 20

5.5 lbs. dried malt extract
(light, unhopped)
1 lb. brown sugar
0.75 lb. roasted barley
7 AAU East Kent Goldings hops
(1.4 oz. hops at 5% alpha acid)
Wyeast 1728

Heat 3 gallons of water to 160° F. Crush barley and place in a nylon grain bag. Steep barley in heated water for 30 minutes. Do not allow the water temperature to drop below 150° F. After steeping, heat the water to a boil. Shut off heat and add extract. Stir thoroughly and bring to a boil. Boil for 1 hour, adding the hops immediately after the boil begins. Add the brown sugar with 15 minutes left. Make sure to stir well. When the boil is finished, add 1 gallon of cold, aerated water to your fermenter. Pour wort into fermenter. Cool wort to between 60° and 65° F. Pitch two-liter yeast starter and top up to 5 gallons with water. Ferment for 7 days at 60° F. Rack to secondary. Ferment for 14 days. Bottle condition for 14 days, then serve.
53rd  and 3rd Rye Brown Ale
(5 gallons, all-grain and flaked rye)
OG = 1.050 FG = 1.012 IBU = 34

6 lbs. pale malt (2-row)
0.75 lb. flaked rye
0.75 lb. chocolate malt
10 AAU Cascades hops
(2 oz. hops at 5% alpha acid)
Wyeast 1056 or White Labs WLP001

Combine pale malt, flaked rye and chocolate malt. Mash grains at 152° F for one hour. Raise mash temperature to 168° F for 5 minutes then recirculate wort for 15 minutes. Collect 4.5 gallons. Sparge water should be at 168°F. Add 1.75 gallons of water to make 5.75 gallons. Boil the wort for an hour. Add hops immediately after boiling starts. Cool wort and siphon to the primary fermenter. Aerate wort and pitch two-liter yeast starter. Ferment for 7 days at 68°F. Rack to secondary fermenter for an additional 7 days. Bottle beer and condition 2 weeks.
Partial-mash option: Replace 2-row pale malt with 1.5 lbs. 6-row pale malt and 3 lbs. dried malt extract (light, unhopped). Make a partial mash of the pale malt, chocolate malt and flaked oats. Hold mash at 152° F for 30 min. Rinse grains with 1 qt. hot water (170° F). Bring wort to a boil, add extract.

Sorghum Porter
(5 gallons, all-grain with sorghum)
OG = 1.052 FG = 1.012 IBU = 40

4 lbs. pale malt (2-row)
2 lbs. Munich malt
1 lb. sorghum
1 lb. crystal malt (30–40° L)
0.5 lb. chocolate malt
0.5 lb. roasted barley
12 AAU Northern Brewer hops
(1.2 oz. hops at 10% alpha acid)
Wyeast 1272

Crush barley malts and sorghum separately. Mix sorghum with 1/4 lb. pale to make a mini-mash. Hold mini-mash at 158° F for 15 minutes, then boil for 45 minutes. Combine mini-mash with the crushed barley and barley malts. Hold mash at 122° F for 15 min. Raise mash temperature to 150° F for an hour. Heat to 158° F for 5 minutes and mash out to 168° F. Recirculate wort for 20 minutes, then collect 5 gallons of wort using sparge water at 168°F. Add 1 gallon of water to make 6 gallons. Boil wort for 1 hour, adding the hops right after the boiling starts. When finished boiling, cool wort and siphon to a primary fermenter. Aerate and pitch two-liter yeast starter. Ferment for 7 days at 70°F. Rack to secondary and ferment for 7 more days. Bottle, condition for 3 weeks and serve.