Medium- vs High-Temperature Alpha-Amylase: Choosing a Grade

Select the alpha-amylase grade around the temperature at which it must remain active. A medium-temperature grade can suit a cooled, cooked slurry; a high-temperature grade is the candidate when liquefaction must overlap with hotter processing.

Match the full temperature history

Record the addition temperature, heating ramp, maximum temperature, holding time and cooling period. The vessel set point can hide local hot spots or slow heating in thick starch. The most useful question is whether sufficient activity remains throughout that history, rather than whether a nominal optimum overlaps one measurement.

What the current product listings say

Scientific & Technical lists its medium-temperature alpha-amylase at a minimum of 2,300 FAU/g with an operating range of 15–65°C. The high-temperature listing states 30,000 U/mL and 15–99°C. These are catalogue specifications checked on 23 September 2026; confirm the current technical sheet and batch certificate before developing a production recipe.

Do not compare the activity numbers directly

FAU/g and U/mL differ in both assay definition and concentration basis. Dividing 30,000 by 2,300 does not establish an equivalent dose. Compare the products in the actual substrate using the same endpoint, or obtain a validated conversion for equivalent assays. Density alone cannot reconcile different activity methods.

Treat starch preparation as a separate variable

A high-temperature enzyme does not remove the need for suitable dispersion or adequate starch accessibility. Prepare each trial with consistent solids, particle size and cooking history. Record mixing torque or viscosity so a dispersion problem is not mistaken for low enzyme activity.

Frequently asked questions

Is the high-temperature grade always better?

No. A lower-temperature process may not benefit from heat tolerance, and the stopping step may be easier with a different grade.

Does the upper listed temperature mean indefinite stability?

No. Temperature tolerance depends on holding time and the process matrix; obtain a stability recommendation for your conditions.

Troubleshooting

• Thick patches remain: inspect dispersion and local heating before escalating the dose.
• Viscosity changes after the stopping step: test residual amylase activity through the actual cooling and storage profile.

Evidence and scope

These are proposed development comparisons, not validated production recipes or guaranteed performance results. Use current grade-specific technical data for the starting dose and operating conditions. Record the enzyme lot and assay definition, and confirm performance in the finished process before scale-up.

Related technical guides

Alpha-Amylase vs Beta-Amylase vs Glucoamylase: Which Do I Need?

What Does Pullulanase Do in Starch Saccharification?

Alpha-Amylase for Oat Milk: Liquefaction and Viscosity Control

Process development and supply

Share your feedstock, batch size, temperature and pH profile, treatment time and target specification with Scientific & Technical. Select a relevant product below to see current pack sizes, price and availability, and buy online. For blends and kits, confirm the component selection and conditions against your intended application.

Follow each preparation’s technical and safety data sheets, including storage and handling instructions. Avoid generating enzyme dust or aerosols.