Description of a typical tomato ketchup processing operation. The process described herein is a “batch type” i.e. non continuous.
Normally tomato ketchup is being produced from existing tomato paste during the off season, rarely is produced on-line from fresh tomatoes.
Tomato paste at 30/32°Brix Hot Break type is being pumped from aseptic storage tanks or from 200 L aseptic bags-in-drums into the first mix tank. Drinkable/softened water is being added in a volume such to reduce the solids content down at 15 –16°Brix. The quantity of paste is controlled by a weighing station where the drums are placed.
In a separate tank the sugar syrup preparaton takes place. Sugar powder is added by a warm screw conveyor and pre-warmed water is fed and controlled by magnetic flowmeter. The two products are mixed in the tank up to a concentration of 50/55°Brix and then sent to a storage tank previous filtration through paper filters.
In other two tanks the sturch and salt are prepared.
Storage tanks are forseen for vinegar and demineralized water. Finally all these ingredients are added in the quantity required by the recipies in the mixer/heater where are put directly also the microelements, such as spice, peppers ecc.
After a suitable mixing and cooking time the final product is discharged into an insulated storage tank.
The final mixture (ketchup) can now be pumped by an homogenizer through a tube-in-tube heat exchanger in order to be pasteurized at 99/104°. After this, the ketchup is deaerated into an under vacuum deaerator from which product will come out at about 88-90°C ready for hot fill into the final container (glass bottles, plastic bottles, etc).
If the chosen container for final product cannot be hot filled at 88-90°C cold filling process shall then be used. In this case ketchup from deaerator shall be cooled down at 32-37°C by an aseptic tube-in-tube heat exchanger then pumped to the “clean room” for filling into the appropriate containers.
It is recommended that all heat exchangers are made of special stainless steel of titanium alloy or high molybdenum content due to the severe corrosion properties of the ketchup.
There are a lot of different recipes for ketchup, FENCO can provide custom-made recipes to its clients according to the taste of consumers of that particular market.
Very common is the packaging in bottles which can be plastic or glass.
In case of plastic, multi layer polyester/polypropylene containers are advisable, more expensive, but performing better filling at temperature up to 95°C and providing better oxygen barrier.
The filling is performed by a specific volumetric filler equipped with recirculation system in order to keep at the right temperature the product during production. After the capping phase the bottles go to a tunnel pasteurizer where it is reccomended to hold at about 80 – 85°C for 7 – 8 minutes and then cooled at 45°C and dried ready for labeling and for final packaging in carton or shrink-wrapped film.