Jet Cooker for Starch Processing

A starch jet cooker is designed specifically for heating high solids slurries derived from starches, such as potato, wheat, tapioca, rice, and corn. Industrial starch cooking is an important chemical process for starch wet milling, grain ethanol production, and other industrial starch processing applications.

The ProSonix C- Series starch jet cooker delivers rapid cooking of the starch with precise temperature control. Steam is continuously injected into the flowing starch slurry through an injector coaxial to a starch condensing tube. The steam and slurry are mixed completely which delivers a superior end product as compared to traditional heat exchangers, steam spargers, and steam eductors. Steam mixing valves and steam sparging when done incorrectly can lead to steam hammer, poor starch cook-out, and poor temperature control.

Because starch and steam are flowing continuously, there is no plugging or fouling of the heating surfaces to hinder the heating process. Most importantly, the starch slurry is intimately mixed with the steam. This results in rapid and complete starch hydrolyzation and more complete cookout of the starch.

Starch cook temperatures can be precisely maintained, allowing the process to be fine tuned to the needs of the final starch product. Cook temperatures from 160°F to 300°F (71°C-149°C) are common. Starch can be cooked at dry solids levels up to 40%. This reduces water use and saves energy by reducing evaporative costs.

C-Series Features

PSX Jet Cooker Technology

  • Co-axial Jet Cooker design assures optimized starch slurry heating & complete starch cook-out
  • Unique PSX Jet Cooker drive system assures concentric slurry gap
  • Adjustable starch slurry gap for variable pressure drop control
  • High gear drive turndown allows for repeatable performance
  • Precise temperature control of +/- 1 deg F
  • Integral Actuator eliminates steam control valve requirements
  • Positional steam inlet simplifies installation
  • Wear resistant coatings available for abrasive starch slurries
  • Suitable for a wide variety of starches such as corn, rice, tapioca, etc


PSX C-Series Jet Cooker with OptiShear Auto Drive

In Starch cooking, proper agitation or “shear” is required to optimize the thermal effect of the steam on the starch particles. The OptiShear Jet Cooker is equipped with an adjustable Condensing Tube (CT). The adjustable CT can be positioned to vary the gap relative to the steam nozzle, creating a narrow slurry gap. This narrow gap between the CT and steam nozzle, optimizes the steam exposure to the thin ribbon of starch slurry, as it enters the CT. By changing the position of the CT relative to the face of the steam nozzle, back pressure inside of the OptiShear can be optimized to reduce uncooked starch and enzyme usage. The OptiShear™ is a unique method of automatically controlling the gap the starch slurry passes through between the condensing tube and the steam injector. The OptiShear is operated electrically from the customers control system.

  • PSX Jet Cooker adjustable slurry gap allows for variable pressure drop
  • OptiShear drive allows for remote auto positioning & control of starch slurry gap
  • High gear drive turndown improves maintenance reliability
  • AC Motor Drive
  • Forward/Reverse control along with optional Position Feedback
  • No proprietary software or controls required
  • Gives Starch Processors ability to seamlessly integrate auto control of Jet Cooker into existing Plant control system

Industrial Design Drive Assembly for Reliable Starch Slurry Gap Adjustment

Radial Slurry Flow

In the OptiShear design, the condensing tube and steam nozzle interface is truly coaxial, insuring the starch slurry gap is uniform throughout the full 360° flow path. The tube rests on multiple bearing surfaces so there is no movement of the tube relative to the injector except to adjust the gap.

Advanced Drive System

The tube movement in the ProSonix heater to adjust the starch gap is accomplished using a threaded engagement. The tube is rotated and an external thread moves the tube towards or away from the injector (nozzle). Moving the tube in this way changes the orientation of the tube inside the heater, causing any wear spots of the tube to move as well. This has the beneficial effect of evening out the wear of the internal parts and extending their operating life.

Jet Cooker Available for Pilot Lab Applications

ProSonix offers a lab scale jet cooker that allows for small scale operation that mimics the performance of the production scale jet cookers. The lab cooker runs a jet cooker in lab scale conditions with very low flow rates. Our pilot cooker is unique in that is designed for the low flow rates.


Internal Steam Modulation

The ProSonix OptiShear Jet Cooker is designed for starch cooking, wet mill processing of starch, ethanol production, and fructose and alcohol production. ProSonix unique method of direct steam injection utilizes via an integral Pneumatic Actuator and variable position steam plug, to accurately meter the mass flow of steam, through choked flow conditions. Choked flow is the phenomenon of accelerating a vapor to maximum velocity by creating a pressure differential through an engineered opening. By establishing choked flow, the steam mass flow can be metered to precisely control the heating of the liquid. This produces predictable results based on position of the stem plug. Through a variable-area steam diffuser, steam flow is metered at the point where steam and liquid first contact and mix.


  • Corn wet milling
  • Fructose production
  • Ethanol production
  • Wet end starch cooking
ProSonix Improves Starch Jet Cooker Performance
A starch jet cooker utilizes steam injection heating for starch cooking applications. Typical applications include starch liquefaction to produce sugar based products such as corn syrup, glucose, fructose and other products. Next stage products are the production of alcohol for fuel-based ethanol production. Designs of jet cookers vary with steam injection heating being a core function. Most critical function of a jet cooker is a variable flow steam injector and adjustable position steam condensing tube. Both features insure proper mixing of steam and starch slurry for improved starch conversion yield. Jet cookers are sometimes referred to by common generic brand names such as hydroheater jet cooker or pick heater. Using a generic brand name to select your jet cooker may limit your options. When selecting your starch jet cooker, make sure you specify the brand name you are looking for. The ProSonix jet cooker offers starch jet cooker design with and integral internally modulated steam control flow design. This design assures complete mixing of steam in the starch slurry for complete hydrolyzation of the starch for improved starch cook-out yields. Precise temperature control and can eliminate rough operation from steam hammer (also referred to as water hammer) for trouble free operation. Just searching for or requesting a hydroheater jet cooker or pick heater may lead to selecting the wrong heater. Our ProSonix jet cooker is a good choice for grain (corn, rice, tapioca, etc.) starch processing and fuel ethanol production.