By Jerri Cook – No one can argue that in the long run, we all benefit from food preservation methods. We do it to save money and conserve resources. For the sake of self-sustaining living, we grow as much of our own food as we can, what we can’t grow we buy in bulk, all with the goal of filling our pantries without emptying our pockets.
Every culture that has ever existed on Earth has employed food preservation methods in some form. However, until the 19th century, your options for preserving food included: drying, fermenting and salting food preservation. This made for some slim vittles during the dark months of winter, until Napoleon came along.
A Tale of Two Frenchmen
The Napoleonic Wars were a series of conflicts that threatened the rule of Napoleon Bonaparte from 1804-1814. Known as one of the world’s greatest strategists, Napoleon knew the biggest challenge in keeping insurgents at bay was to ensure his army was always ready. “An army marches on its stomach,” claimed Napoleon.
In order to keep the French army fit and fed, the government offered 12,000 francs to anyone who could come up with a food preservation method that would allow an army on the move to eat well. This meant preserving and transporting large amounts of food.
Nicolas Appert, a baker living in Paris, claimed the 12,000 francs in January of 1810, 50 years before Louis Pasteur would discover that heat kills harmful bacteria. Appert’s process involved packing food into glass jars, sealing them tightly with cork, and boiling the sealed jars for a period of time. Even though Appert could not explain why the process worked, the French government was convinced that it would aid the military in squashing the increasing number of uprisings by keeping the troops fed and healthy.
Although transporting glass was an issue, it would only be a few more years, after Napoleon’s defeat at Waterloo, until the metal can was invented, allowing the world’s armies to march further and fight longer on full stomachs. The process of storing food in cans led to the “Type C Ration,” or c-rations as the canned meals were called by American soldiers. Containing inexpensive, high-calorie food designed to meet the nutritional needs of soldiers in combat situations, the instant meals would later become an iconic piece of American military history. While the tin can eventually replaced the glass jar in European and American food processing plants, glass jars remained the choice of home food preservers.
Big Mouths and a Steaming Hot Bath
The jars used by Appert were glass bottles with large mouths. The food was placed into the bottles which were then sealed with cork and wax for processing in hot water. The process worked, to be sure, but it was messy and the equipment was cumbersome. It wasn’t until 1858 when John Landis Mason patented a new jar with a screw-on zinc lid that home-canning became common. Other inventors and other jar designs soon followed. Atlas, Ball, and Kerr became household names alongside Mason. With each improvement in design, the jars and lids became easier to use, and canning became a widely accepted practice, but it had its limits.
While boiling sealed jars did kill some harmful bacteria, it didn’t always kill all of the harmful bacteria. As a result of “bathing” sealed jars in hot water, the bacteria Clostridium botulinum often thrived. Botulism is a fatal form of food poisoning that arises from improperly canned meat, vegetables, and fruit. Leaving the jars in the hot water for hours would destroy the consistency and quality of the food before it would destroy the botulism. People became leery of eating home-canned food for fear of becoming deathly ill. It seemed that Appert’s process was suited only to high-acid fruits and vegetables. Meat and lower acid foods were best preserved by curing or drying, not canning.
The first pressure canners intended for home use were introduced near the turn of the 20th century. They were large, bulky and not always the safest contraptions, but by the end of WW II food technology had advanced, and home pressure canners became less burdensome and much safer. The new aluminum models were lighter, heated more evenly, and used less water than the older ones.
The trend after the War was away from dial gauges to weighted pressure gauges that made reaching and maintaining the correct pressure a simple proposition. No more trying to tweak the heat to get to just the right reading on the dial. It was now as simple as placing a weight over the petcock and listening for the smooth rhythm of pressure escaping.
Even as we begin the 21st century, food science is changing the way we use pressure canners. Today’s pressure canners are sleek as well as functional. Standard safety features such as hidden locks prevent users from inadvertently opening the canner before it fully depressurizes, decreasing the number of severe burns caused by the premature opening of a pressure canner. Modern pressure canners are taking some of the fear out of home food preservation methods.
If you’ve never canned before, or have one of those old reliable canners that works just fine, but you have to babysit all the time, you might want to consider buying a new pressure canner as your preferred food preservation method. Not that you can’t find perfectly good and functional pre-WW II canners. You can, and many have. But the newer ones are much easier to work with, not to mention safer. Just remember that a pressure canner and a pressure cooker are two different things. Pressure cookers are for preparing meals, and pressure canners are used for preserving food in glass jars. Make sure you purchase the right type.
Practice Makes Perfect
Like any other homestead art, perfecting pressure canning recipes requires that you spend some time getting to know your equipment and becoming comfortable with how it operates. There’s no shortcut for this. Spend some time with the manual that is included with your pressure canner. Discovering how this food preservation method works and how you fit into it is the first step to a successful experience. The last thing anyone wants is a traumatic experience brought about by insufficient planning and unfamiliarity with the equipment.
In addition to buying the wrong type of pressure vessel (a cooker instead of a canner), people make other common mistakes that can seriously impair the outcome of their attempts at canning. The most serious of these mistakes is not doing a “dry” run with the new pressure canner. While it may seem like a lot of work to set up the canner with only empty jars and then proceed to run the full gamut of pressurizing and de-pressurizing the canner, this is a crucial step that should never be skipped and should be performed each year before you start canning in earnest. This preliminary process will not only familiarize you with a new canner, it will also expose gasket problems and other issues that could cause you or your family serious injury.
No Rocket Science Required
Canning as a food preservation method isn’t rocket science. We know that for a fact. A rocket scientist didn’t invent it; a baker in Paris did that. Like Appert, you don’t have to know why canning works. You just have to know how to use your equipment as safely as possible. Once you’re ready, you’ll find recipes for canning just about everything you can imagine (and a few things you would never imagine) in the pages of COUNTRYSIDE. If it can be preserved in a pressure canner, our readers have done it. Over the decades, readers have shared food preservation methods and recipes for everything from canning soups to canning cake. Both Napoleon Bonaparte and Nicolas Appert would be impressed.
Originally published in 2011 and regularly vetted for accuracy.