Replacing Part of the Malt: Alpha and Beta Amylase for Adjunct and Barley Mashes

During malting, barley builds up its own hydrolytic enzymes, and in the mash those enzymes, or added ones, break starch and protein down into soluble small molecules. With a normal malt grist, the extract rate can reach about 80 percent. Some plants replace more than half of the malt with raw barley and add enzyme preparations instead; the extract rate on that route is only 67 to 69 percent, but the beer shows good foam and higher non-biological stability.

As enzyme supply has grown, more brewhouses saccharify with added enzymes, because the cycle is shorter, extract recovery rises and stability is easier to control. Added enzymes are used mainly to treat adjuncts and to make up for activities the malt is short of. The enzymes in common use are an alpha-type liquefying enzyme, beta-amylase, beta-glucanase, neutral protease and compound blends.

For a buyer the decision is a trade: cheaper grain against lost extract, so the enzyme program is priced against the extract and stability your own trial delivers.

Beta amylase is most valuable when the mash needs additional saccharifying power after starch has been made accessible. In adjunct brewing, raw material pre-treatment and gelatinization are often the limiting steps; beta amylase cannot efficiently convert ungelatinized starch or bypass alpha-1,6 branch points. A thermostable alpha amylase may be used earlier for liquefaction, followed by a beta-amylase rest to increase maltose. In high-gravity brewing, the goal may be higher fermentable extract without excessive viscosity or unpredictable attenuation. The enzyme program should match yeast capability, beer style, and downstream filtration or separation limits. For malt extract and syrup production connected to brewing supply chains, beta amylase can support maltose-rich profiles, but specifications should state target DE, maltose percentage, solids, color, and flavor constraints before enzyme selection.

Use alpha amylase where liquefaction or viscosity control is limiting. • Use beta amylase where maltose formation and fermentability are limiting. • Define sugar-profile targets before locking dosage and mash schedule. • Validate adjunct pre-treatment before blaming enzyme performance.

Beta-amylase dosage must be set against the supplier's declared activity, process temperature, grist composition, residence time, and target fermentability. Product weight alone is not comparable between suppliers, so ask for the screening band in activity units on the TDS. Start with a control mash, then run at least three dosages under identical mash thickness, pH, calcium level, and rest time. Measure wort gravity, maltose, glucose, maltotriose, limit dextrins, viscosity, iodine reaction, and fermentation attenuation. The best dose is not the highest conversion result; it is the lowest reliable dose that reaches the beer specification without negative flavor, filtration, or cost impact.

Confirm dosage on an activity-unit basis. • Run control, low, medium, and high enzyme treatments. • Calculate cost-in-use per hectoliter or per metric ton of grist. • Avoid overdosing if fermentability and filtration targets are already met.

Adjunct type and share of the grist (raw barley, rice, corn grits or other), and whether it is cooked before mashing. • Malt quality and grind for the current lot. • Target extract, fermentability and wort strength for the beer or malt extract you sell. • Mash schedule: thickness, beta-amylase rest length, the hotter step and mash pH. • Which enzymes the grist is short of: liquefying, saccharifying, beta-glucanase or protease. • Activity definition and screening band from the TDS, so offers can be compared per unit of activity. • For the quote: product or grade, quantity per order or per month, and destination country.