Traditional crafts- up in smoke

Though the science of smoking food has evolved, the practicality has barely changed over hundreds of years.

Smoking food is one of the oldest forms of food preservation – and has likely been used by Mankind almost as long as we have used fire for cooking. Used for meat and fish, it would mean that a successful hunt would provide meat for far longer – and it was used all over the world, in varying forms, alongside air drying.

There are three smoking processes: cold smoking, which gives a long preserve without cooking the meat; hot smoking, which will help with a bit of preservation, and cooks the meat; and smoke roasting – cooking over a fairly fierce heat with smoke, which doesn't preserve the meat. In this piece, we'll look at cold-smoking.

Cold smoking was, alongside brining (the use of salt) and drying our only way of preserving protein. Essential for our hunter-gatherer ancestors, it also became essential for our farming ancestors when an animal was slaughtered. The process involves brining and sometimes air-drying for a period of time before smoking. Along with the smoke, the salt will help to inhibit the development of bacteria that could spoil the meat or fish. During the smoking process, the meat or fish will lose weight – and the more weight – or liquid – lost, the longer the ingredient will keep. So the brining is an essential part of that, too, helping to reduce the water in the meat or fish and thus reduce the humidity during the smoking.

A dry or wet brine can be used, and other ingredients can be added at the brining stage for flavour – sugar, bay leaves, juniper for example. Once the ingredient has been brined, it might be washed or wiped and then likely dried for at least a few hours to remove any residual dampness before being smoked.

The cold smoking process doesn't cook the meat or fish – it is done over indirect smoke, reaching temperatures between 10 and 29C. Many cold-smoked ingredients are then eaten "raw", such as smoked salmon, cod's roe and beef filet, but others, such as kippers and cod fillets, need cooking in the kitchen.

In Europe, alder was always the traditional wood used for smoking, though oak and beech are more widely used today. The North Americas used hickory, mesquite, oak, pecan, maple and fruit tree woods such as apple and cherry or even burning corn cobs. The Chinese use uncooked rice and sugar to smoke tea, while peat was dried and used to smoke barley malt to make whiskey. Probably the least tempting is the Icelandic tradition of using dried sheep dung for fish, lamb, mutton and whale.

For centuries, many fishing villages and farms would have had a smoke house, or at the very least a nook in a chimney, it wasn't until the 1930s that an effective kiln for mass-smoking was invented – the Torry Kiln. It was developed at the Torry Research Station in Scotland (the Department of Scientific and Industrial Research, set up near Aberdeen to research how to preserve fish and avoid wastage) and is the prototype for all large-scale smokers today.

Though the science behind smoking is much better understood, the practicality of it hasn't changed – meat and fish, salted, then dried, then smoked, will taste delicious and keep for much longer – so it's a winner all round.