All kinds of rewards – be aware of the risks.
Like many things, the process of super-heating wine for preservation purposes had been known in China for millennia before discovery in the west.
However, the Chinese had no idea what micro-organisms were or consequently why this process worked until Antonie Van Leeuwenhoek first observed the little friggers in 1665.
Microorganisms continued to ruin people’s food until the French chef Nicholas Appert pioneered the modern canning process. Appert would take foodstuff like jellies, syrups, and soups and seal them in bottles with cork and wax and then boil them. The end result was a remarkable food product that could be shipped and held for extended periods of time without spoiling. He did this to win a prize from Napoleon.
It’s hard to overstate the importance that this discovery had on the industrial world considering it is in use in basically every food retail outlet on the planet, virtually unchanged. Appert then converted his workshop into a bottling plant and made all kinds of wacky bottled products, including an entire bottled sheep. Science.
The main opponent to today’s home bottler is: Botulism.
This bacterium produces a neurotoxin that will kill you like it did 4 people last year who probably never READ THE INSTRUCTIONS.
Botulism is found in soil and is on pretty much every piece of produce that comes from underneath the ground.
Botulism is anaerobic. This means it only lives in conditions with little or no oxygen. Until it reaches these conditions, it lives as a spore (think seed). These spores are very difficult to destroy – regular boiling requires upwards of 8 hours. If not properly destroyed, these spores come to life in the oxygen-less environment of the bottle and start producing toxins.
Bottling foods can be divided into two categories: Low acidity foods (PH > 4.6) and High Acidity Foods (PH <4.6). High acidity foods are too acidic to allow the growth of Botulism. They allow you to use regular boiling water to sterilize and seal your jars.
Low acidity foods ARE NOT acidic enough to kill Botulism. In order to safely bottle these foods, you must either lower the PH to below 4.6 OR process them in a pressure canner at above 10PSIG.
Pressure canners create high-pressure environments that allow the temperature of steam to get much higher than 100 degrees Celsius. Without this additional pressure, regular boiling requires up to 7 constant hours of boiling.
Some of the easiest things to bottle at home are the classics: pickled beets or mustard pickles. With a brine of 50% vinegar, they are WAY too acidic to be bothered by botulism and can be done in a regular, flat-bottomed stockpot.
I will not list the whole procedure here; every step in bottling is crucial and is unique to the material that you are bottling. Go online and follow the steps exactly.
The real purpose for bottling in a modern context is that some things are just too precious to throw away – seasonal produce, game meat, or a way-too-big pot of pea soup.