Steam Infusion Vaction Unit

The Steam Infusion Vaction™ Unit is a disruptive device that sits within a cooking vessel and uses steam as the motive force to heat, mix and pump liquids with and without particulates.

OAL acquired the PDX Sonic technology developed by Pursuit Dynamics in 2013 and have since successfully commercialised the Steam Infusion Vaction™ unit.

A full understanding of the operating parameters was gained under a £978,236 Innovate UK  project with the University of Lincoln and a leading UK food manufacturer.

The combination of a growing commercial install base and scientific research have allowed us to idenifty the cooking applications where Steam Infusion offers the most value in terms of product quality and operational efficiency.

 
 

How Steam Infusion works?

Ian Beauchamp, OAL Head of Process, explains how the Vaction™ Unit operates in the video below:

The fluid to be processed enters the OAL Vaction™ Pump and once flooded, culinary steam is introduced into the unit. Special profiling within the steam chamber accelerates the velocity of the steam to above the speed of sound. The steam passes into the mixing chamber through an annular nozzle, disrupting the fluid flow and breaking it into small droplets, referred to as the vapour phase.

The small droplets within the low pressure vapour phase offer a significantly increased product surface area for the steam to condense into, generally resulting in a temperature gradient in the order of 12oC. This provides for no hot surface contact / hot spots so preserving the quality of the product and minimising Maillard Reaction and caramelisation of certain sugars. 

As the steam condenses into the fluid droplets, the pressure rises. This is referred to as the condensation shock-wave and generates a pumping effect.

The low pressure vapour area within the reactor assists in the transfer of flavours and the effective hydration of starch granulates providing the opportunity to potentially reduce ingredient additions whilst still maintaining similar taste and mouth feel for the products produced.

Reduced hot contact surface areas diminish occurrences of product burn-on and hence the need for aggressive CIP regimes. This assists in reducing CIP chemical usage, cleaning operations and waste water disposal.  

 
 

Condense More Steam into your product...

The disruptive nature of the Steam Infusion process means food manufacturers can get more energy into their products faster; shortening cooking times and stopping the compromise between speed and product quality.

Traditional steam injection relies on contact time between the steam and the product to condense into it. If the pressure were to be increased, the contact time would be reduced as flow rates increase and steam could fail to fully condense remaining in a gaseous state and exiting the system as steam. This inefficiency will increase as
the product temperature and temperature difference between the product and steam reduces. Steam injection, therefore, leads to an inversely proportional relationship between efficiency and heat up times as steam pressure is changed leading to compromises.

While increasing pressure in a steam jacket could increase heat transfer into the vessel, the product would be more susceptible to burn on damaging the product and requiring a more thorough clean. It would also demand a higher pressure rated, more expensive jacket.

With the annular design of the Vaction™ Unit allowing steam to condense within the unit itself, the heating process does not rely on contact time between the steam and the product and it has the ability to run at comparatively higher steam pressures without compromising on efficiency.

The results are shown in the graph below that compares the heat up times of different steam cooking technologies.

 
 

No Exposure to high temperatures...

The Steam Infusion Vaction™ unit eliminates burn on contamination by preventing exposure to excess high temperatures. The technology cooks from the centre of the vessel and the low pressure vapour phase coupled with the short residence times mean the ingredients do not see excess temperatures whilst processing.

The images below show the state of the cooking vessel following bechamel sauce trials during our Innovate UK project trials. 

Steam Jacket Dairy Sauce Cook

Steam Infusion Dairy Sauce Cook