Complaint
Canned foods are a significant component of the diet of most individuals in developed countries, offering food in a convenient form with year-round availability. The canning process relies on heat treatment for the destruction of microorganisms and preservation of the food, which is then generally considered to have an indefinite microbiological shelf-life providing that pack integrity is maintained. The extent of the thermal processing, in terms of both temperature and duration of the treatment, is dependent upon the chemical and physical composition of the product. Both physical and chemical changes occur during processing and, to a lesser extent, during storage, and it is these that determine the product quality in terms of its sensory properties and nutrient content. These changes, which can be either desirable or undesirable, are influenced by the time and temperature of the process, the composition and properties of the food, the canning medium, and the conditions of storage.
This article will consider the changes that can occur during canning and their effect on the quality of the product.
First, fresh produce such fruit, vegetables, meat or fish is picked and caught at its prime and taken directly to canning factory.
Produce is washed under fast water jets and then peeled, trimmed, cored and sliced as appropriate before it is packed into empty cans moving fast along a conveyor belt.
Liquid such as brine, water, oil, syrup or fruit juice is added to fill the can.
The lid is sealed on top and tested for air tightness.
Each can is sent to be cooked. The cans are stacked in large cookers that heat them to right temperature and under the right pressure for the type of food being cooked. As cans are sealed beforehand, any micro-organisms are killed off in the cooking stage. Through this process, cans remain fresh with the nutrients locked in until opened.
When the cans have cooled, they are labelled and sent on their way to shops up and down the land and then finally to your kitchen cupboard.
