Canning

In this video, we show you how one of the most common food processing technologies is carried out – preserving food in metal cans.

Tinned tomatoes

Tinned or canned tomatoes are a staple item in many kitchen cupboards. All canned tomatoes are one of two tomato varieties: standard garden vine tomatoes and plum tomatoes, both of which are peeled before canning in juice or purée. The structural strength of plum tomatoes makes them ideal for canning. They are meaty and contain less juice and fewer seeds, which means they maintain their shape in the can. Garden vine tomatoes function nearly as well but have a different flavour profile and a different shape. All canned tomatoes are cooked in the can during the sterilization process, which ensures their safety and long shelf life. One drawback of canned tomatoes is that with prolonged exposure to the aluminium of the can, the acid from the tomatoes interacts to cause tomatoes to adopt a ‘tinny’ taste. This can be avoided by coating of the inside of the can to prevent direct contact. This used to be mainly through use of an epoxy resin, but these coatings contained bisphenols, including bisphenol A (BPA), which was linked to health concerns. Food can linings are now typically made from acrylic and polyester.

The journey to canned tomatoes. ©EUFIC Source