Tuna

Tuna is a type of fish. It is part of the Scombridae family of fish, which also includes mackerels. People are often surprised by how large tuna are, because they are often consumed from cans (and in sandwiches), and if you're not really a 'foodie' you may never see one whole. A fully grown bluefin tuna can grow up to over 10 feet (3 metres) in length. They can be found in most of the world's seas, apart from those at the poles. Tuna are migratory fish, and migrate once a year, according to the warm and cold seasons. Unfortunately, the popularity of tuna and mayonnaise sandwiches (among other uses for tuna) has contributed to over-fishing and the decline of the species. There are various varieties of tuna, the most popular for eating being the yellowfin, bigeye and bluefin tunas.

If the tuna is from a can it may be stored in brine (salt water) or some type of vegetable oil, mainly sunflower. In a sandwich, the tuna is often mixed with mayonnaise, as it can be quite dry on its own. If you buy tuna, it is important to only buy tuna that is marked as 'dolphin friendly'. This tuna has been caught using methods that do not harm dolphins.

Mayonnaise

Mayonnaise¹ is a mixture of egg yolk, vegetable oil, mustard and vinegar. You may wish to make your own mayonnaise, but it is available from all supermarkets, in either glass jars or squeezy plastic bottles. It is easier to get mayonnaise out of jars, even though the squeezy bottles are supposed to be more convenient to use. You may need to employ a long handled spoon or knife in order to retrieve the mayonnaise, especially if you are coming near to the end of the jar. You may also wish to take materials recycling into consideration when purchasing your jar or bottle of mayonnaise.

Bread

It is important to choose the right sort of bread for your sandwich. The bread you choose will depend on personal preference to some extent, but you should also try to bear in mind that a tuna and mayonnaise sandwich can become rather soggy over time, so it is best made on a substantial bread, such as a seeded brown loaf, rather than a white sliced processed bread.

How to make your sandwich

There are two ways in which you could make your tuna and mayonnaise sandwich. The first is the classic mix method, where the tuna and mayonnaise are pre-mixed in a bowl before being spread on the bread. In the second method the mayonnaise is spread on the bread first, followed by a layer of tuna on top. It is up to the indivdual as to which method is used.

Possibly the most important thing to remember when making a tuna and mayonnaise sandwich is that you must drain the tin of tuna. Failure to do so will result in an extremely soggy and possibly inedible sandwich. Once the tuna is drained you can follow either of the methods described above: spreading the mayonnaise on the bread first or mixing the mayonnaise and tuna together and then spreading it on the bread.

You will also need to decide whether or not you are also going to spread some kind of margarine or butter on your bread, before adding the tuna and mayonnaise. If you choose to use a spread this will make a difference to the calorie content of your sandwich. Although butter or margarine are usually used to stop a sandwich from becoming dry, it is probably unecessary to add either of these to your sandwich, as the mayonnaise should keep the sandwich nice and moist.

If you plan to add sweetcorn to the sandwich it can be added to the tuna or tuna and mayonnaise mix at this stage.

The sandwich maker must decide on the tuna:mayonnaise ratio. Factors that may influence his or her decision include dietary requirements, like or dislike of mayonnaise/tuna, how long the sandwich will remain before being eaten (mayonnaise can help prevent sandwiches drying out), and how much mayonnaise there is left in the jar.

Now for the easy bit: spread your mayonnaise and tuna however you choose onto your bread, add salad if appropriate, and either fold over (if using only one slice of bread) or place another slice of bread on top if using more than one slice. If using the two-slice method you may wish to cut your sandwich in half, into triangles or rectangles, depending on preference. Some sandwich eaters prefer to cut their sandwiches into quarters, creating smaller triangles, or squares. When offering sandwiches to children or elderly people it may be best to cut them into smaller portions.

Once the sandwiches have been cut according to preference or need, serve them up and enjoy them!