Metering Liquid Food Products in Extruded Foods

This application note provides an overview of the successful use of seal-less gear pumps for the metering of food products in the extruded food products industry.

THE INDUSTRY

A long established manufacturer of processed foods incorporates new technologies in the production of extruded, pressed, preformed and otherwise processed foods, such as cereal, biscuits, cereal bars, puffed cereal and other snacks. Extrusion techniques allow the processed food manufacturer to work with brittle materials and to provide products with complex cross-sections and precise finished surfaces. Food extruders are used to combine liquor (oils or malt), water, flavorings and coloring with dry products, such as wheat, maize and rice flour, in a continuous production scheme to produce the finished products.

THE APPLICATION

Dry food products are fed into a twin-screw extruder from a hopper unit. Liquid food products (liquor, water, flavorings and/or coloring agents) are metered into the food extruder where the combined liquid and dry products are cooked at predetermined temperatures, cut into desired shapes and sizes and then processed to produce a range of snack food products. This stage of processing includes drying, toasting, crimping and forming the products.

THE PUMP SOLUTION

Micropump magnetically coupled cavity plate design gear pumps as well as Liquiflo MAX and 4 Series magnetically coupled gear pumps are direct coupled to three-phase inverter rated A/C motors with stainless steel motor bodies to pump the food products accurately into the extruder.

FEATURE	ADVANTAGE	BENEFIT
External Gear Pump Design	Smooth, accurate pulse-free flow	Consistent application of liquid cooking ingredients
	Simple to service and maintain	Reduced downtime and less production lost
Magnetic Coupling	Containment of the pumped fluid	Reduced chemical and environmental hazards - no leakage in the plant
	No rotating seals to fail	Extended pump operation between servicing means reduced downtime
	Leak free pumping	No cross contamination of the pumped liquids
Inverter Controlled AC Motors and Permanent Magnet DC Motors	Motor output speed can be easily adjusted	Amount of liquid can be adjusted automatically
Choice of Wetted Materials	Compatibility with the pumped liquid	Suitable for pumping a variety of food products