The diagram illustrates several processes involved in a commercial production of frozen fish pies. Overall, potato, fish, sauce, and peas are the main ingredients which are prepared separately.
To begin with, the potatoes, which have been delivered up to a month, are cleaned, peeled, and cut into slices. Next, the slices are boiled, then chilled before being stored until needed.
On the other hand, it is noticeable that the production of the salmon is more complicated than the potatoes. To start with, within 12 hours or less of being delivered to the factory, the fresh salmon is cooked by being steamed with a mix of lemon juice and salt. Then, the skins and bones are removed by hands before the inspection process.
After that, it is added peas and sauce to the pies respectively which were prepared before, then the salmon pies are covered by potatoes slices. Finally, after freezing the pies, they are read to being stored or to dispatched.