Alpha Amylase for Glucose Syrup Production — Industrial Liquefaction
Thermostable Bacillus-derived alpha amylase converts 30–35% DS starch slurry into low-viscosity dextrins at 85–95°C, setting up efficient glucoamylase saccharification for glucose and HFCS syrup.
Glucose syrup and high-fructose corn syrup (HFCS) are produced in two distinct enzymatic stages: liquefaction and saccharification. Liquefaction — the first stage — relies entirely on thermostable alpha amylase. The enzyme must rapidly hydrolyse gelatinised corn, wheat, or tapioca starch slurry at 30–35% dry solids (DS), collapsing viscosity from thousands of mPa·s to below 100 mPa·s, and generating dextrins with a dextrose equivalent (DE) of 10–15. Without effective liquefaction at the correct DE, downstream glucoamylase saccharification is impaired, filtration backs up, and final syrup glucose purity falls short of target.
Thermostable alpha amylase from Bacillus amyloliquefaciens and Bacillus licheniformis is the correct grade for glucose syrup liquefaction. Our alpha amylase at 50,000–200,000 U/g operates stably at 85–95°C and pH 5.5–7.0, surviving the thermal profile of jet-cook (105–110°C, 5 min) and main liquefaction hold (90–95°C, 60–90 min) with calcium stabilisation at 50–100 ppm Ca²⁺. The result is a consistent low-DE dextrin stream that enters the saccharification stage with predictable viscosity, colour, and substrate distribution.
Dosage in glucose syrup production is typically 0.5–0.8 kg enzyme per tonne of dry starch solids, split-dosed at slurry preparation (20–30% of dose) and post-jet-cook at the main holding temperature (70–80% of dose). pH is adjusted to 5.8–6.2 using sodium hydroxide or hydrochloric acid before the enzyme addition stage. After the liquefaction hold, the dextrin stream is cooled to 55–60°C and pH adjusted to 4.2–4.5 for glucoamylase saccharification, which converts DE 10–15 dextrins into 95–98% glucose over 24–72 hours depending on system design.
For syrup plant procurement teams, key selection criteria are thermostability profile, consistent lot activity, compatibility with jet-cook calcium requirements, and food-grade documentation. We supply COA, TDS, ISO 9001, HALAL, KOSHER, and food-grade certificates per lot. MOQ 25 kg; container-load pricing is available for continuous glucose syrup operations.
Corn Starch Glucose Syrup Liquefaction
Wet-milled corn starch at 30–33% DS is pre-slurried, pH adjusted to 5.8–6.2, calcium verified at 50–100 ppm Ca²⁺, and alpha amylase dosed at 0.15–0.20 kg/t DS before jet cooking at 105–110°C. Post-flash-cool at 90°C, the remaining 70–80% of the enzyme dose is added for the main hold (60–90 min), achieving DE 12–15. The resulting corn dextrin stream has viscosity below 80 mPa·s and is suitable for direct transfer to saccharification tanks. This process is standard in US and Chinese glucose syrup plants.
Tapioca Starch Glucose Syrup
Tapioca starch from cassava roots gelatinises at 65–70°C, lower than corn. In Southeast Asian syrup plants, tapioca at 28–32% DS is processed through jet cookers at 100–105°C with alpha amylase at 0.4–0.6 kg/t DS. The lower gelatinisation temperature allows slightly milder jet-cook conditions, reducing energy cost. The resulting tapioca dextrin stream is characteristically clearer than corn liquefact, producing glucose syrup with better colour and lower colour formation during saccharification.
HFCS-42 and HFCS-55 Feedstock Preparation
High-fructose corn syrup production requires glucose syrup of 95–97% DE as input to the isomerisation step. This demands a well-controlled liquefaction step with alpha amylase to achieve precisely DE 12–15 — the optimal window for glucoamylase efficiency. Underdosing amylase produces high-viscosity liquefact with residual starch; overdosing creates too many short oligomers that reduce glucoamylase yield. Consistent alpha amylase dosing is the foundation of consistent HFCS production economics.
Continuous Liquefaction Reactor Systems
Large-volume glucose syrup plants operating continuous liquefaction reactors (CLR) require liquid alpha amylase for precise inline dosing via metering pumps. Activity per mL specifications (rather than per gram of powder) enable accurate flow-proportional dosing calibrated to starch feed rate. Our liquid alpha amylase grades are supplied in 30 kg jerricans for pump connection and maintain activity stability in the storage conditions typical of industrial syrup plant enzyme tanks (5–15°C).
| Parameter | Value |
| Activity range | 50,000 – 200,000 U/g (multiple grades) |
| Optimal pH | 5.5 – 7.0 |
| Optimal temperature | 85°C – 95°C (thermostable grade) |
| Form | Light brown powder or amber liquid |
| Shelf life | 12 months (sealed, cool, dry place) |
| Packaging | 25 kg drums / 30 kg jerricans |
Frequently Asked Questions
What is the correct dosage of alpha amylase for glucose syrup liquefaction?
Standard dosage is 0.5–0.8 kg of enzyme per tonne of dry starch solids, applied as a split dose: 20–30% added at slurry preparation before the jet cooker, and 70–80% dosed post-jet-cook at the main holding temperature (90–95°C). This split-dose approach ensures enzyme reaches the starch before gelatinisation and provides continuous activity during the holding step. Tapioca starch may require slightly lower dosage; wheat starch at higher protein levels may require the upper end of the range. Calibrate against actual DE measurement in your process.
Why is calcium required for alpha amylase in syrup production?
Calcium ions (Ca²⁺) at 50–100 ppm are essential cofactors that stabilise thermostable alpha amylase at jet-cook and holding temperatures. Without adequate calcium, the enzyme undergoes thermal denaturation faster than the liquefaction hold period requires, resulting in incomplete starch hydrolysis and high-viscosity liquefact that impairs filtration and saccharification. Most syrup plants use calcium chloride addition as a standard process step and monitor calcium levels as part of quality control.
What DE range should liquefaction target for glucose syrup production?
The target DE after liquefaction is 10–15 for glucose syrup and HFCS production. Within this range, DE 12–14 is optimal for glucoamylase saccharification efficiency. DE below 10 retains excessive viscosity and reduces glucoamylase accessibility to substrate; DE above 16 begins to generate glucose that can inhibit glucoamylase activity slightly and increases Maillard browning in subsequent processing. Your glucoamylase supplier will specify the preferred DE window for their product.
Is your alpha amylase compatible with food-grade syrup production standards?
Yes. Our thermostable alpha amylase for glucose syrup production is supplied with full food-grade documentation, ISO 9001 quality certification, and HALAL and KOSHER certificates available per lot. COA and TDS are provided with each shipment. For syrup producers supplying food manufacturers or operating under FSSC 22000 or BRC schemes, these documents satisfy standard ingredient QA review. Non-GMO options are available on request for organic or non-GMO certified syrup programmes.
Request Alpha Amylase Pricing for Your Syrup Plant
Specify substrate (flour, mash, starch slurry, fabric, coating), process temperature, pH, and target DE or dosage. We will advise on powder vs liquid and standard vs thermostable grade, ship a free 100 g sample with COA, and quote bulk pricing within 24 hours.
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