Description of a typical tomato “passata” processing operation made from fresh tomatoes.
Production of passata normally takes place during the prime time of the tomato season, when fresh tomatoes offer their best quality; a suitable variety of tomatoes shall be used in order to obtain: high cellulose content, high pectin content, high pulp content and low seeds content. Harvest shall take place only when tomatoes are fully ripe, bright red and sound. Passata must be made only from 100% fresh tomatoes (as far as the Italian law is concerned); the only added ingredients allowed are salt, basil and citric acid. However, several producers do not permit addition of citric acid, and this marketing choice forces them to use only tomatoes having a natural pH lower than 4.4.
Passata processing essentially follows the same steps used for other tomato products, such as:
· Unloading of fresh tomatoes from 300 / 450 kg bins into the feeding flume; it is advisable not to transport tomatoes in bulk in order to protect the fruits from mechanical damage.
· Washing and sorting tomatoes in order to eliminate rotten fruits and all fruits not suitable for good quality production; in the production of passata the sorting operation is a key factor in order to reduce the presence of moulds and improve the quality of the finished product; sorting can be performed not only by hand, but also by electronic/optical devices too.
· The selected tomatoes are then chopped and rapidly heated in the hot-break system. The chopped product shall be heated as fast as possible up to 95/100°C in order to maintain the natural viscosity of the product by deactivation of the enzymes .
· The chopped tomatoes can go now to the twin stage unit pulper-finisher.
· This product can be partially concentrated or as it is to the packaging section. Among the most common packaging types we just mention, the one in brick or in glass bottles. Both of them are made by the hot filling technology.
· Verification of vacuum inside each container with automatic removal of defective containers;
· Final packaging into cardboard boxes or into trays with shrinkwrapping film.