Smokey says... Use fire wisely!

This week we are conducting a new class--Fire Materials Identification Class--and later in September is the 2nd Annual Fire Palooza class where friction fire methods are king.

So, what are we doing here on the EC-Blog to prepare you for these classes? Did you know where there is fire, there is smoke? Have you considered the value of the smoke that fire produces? Despite the bad reputation smoke has gotten, it is the source of our first food preservation technique. Who has not tasted and subsequently enjoyed the smoky flavor of smoked meat or fish like salmon--right?

Smoke preservation originated in early societies and is still used today to preserve mainly fish, meats and grains. It works by drying and dehydrating the food, as well as by neutralizing harmful elements with chemicals such as tars and phenols, that attach themselves to the food and are toxic to microbes and insects. These chemicals can also become harmful (carcinogenic) to humans if consumed in too large amounts. (See the Pryolysis Products of Wood below)

There is archaeological evidence that smoking was known as a method of food preservation at an early date. An archaeological site near the River Bann, Ireland that is thought to have been a fishing camp used in the second millennium B.C. The site bears the remains of several hearths over which their fish are thought to have been smoked. Evidence exists that the Romans probably used smoke to preserve food and to enhance its flavor (Wilson 1991, pp. 15-6).In colonial times, many households had smokehouses which were used to smoke beef, ham, and bacon (Earle 1899, p. 150). Smoking is still sometimes used to preserve fish and meat (Forbes 1955, p. 185).

In developing countries today, it is common to find grain bags hanging from the ceiling in a primitive hut near central fire. The heat and smoke from the open fire can then preserve the stored grains in a cheap manner. Smoked food often has a unique and robust flavor, and is still widely produced because in many situations is the fastest way to preserve food without the use of specialized equipment that may also need sources of energy that requires cash payment, such as gas or electricity.


Pyrolysis Products of Wood
Product - Percent in Mixture

• Acetaldehyde - 2.3%
• Furan - 1.6%
• Acetone - 1.5%
• Propenal - 3.2 %
• Methanol - 2.1%
• 2,3-Butanedione - 2.0%
• 1-Hydroxy-2-propanone - 2.1%
• Glyoxal - 2.2%
• Acetic acid - 6.7%
• 5-Methyl-2-furaldehyde - 0.7%
• Formic acid - 0.9%
• 2-Furfuryl alcohol - 0.5%
• Carbon dioxide - 12.0%
• Water - 18.0%
• Char - 15.0%
• Tar (at 600˚C) - 28.0%

References:
Earle, Alice Morse. Home Life in Colonial Days. New York: The Macmillan Company, 1899.
Forbes, R.J. Studies in Ancient Technology. Vol. III. Leiden: E.J. Brill, 1955.
Wilson, C. Anne, ed. Waste Not, Want Not: Food Preservation from Early Times to the Present Day. Edinburgh University Press, 1991.