Know your altitude!
Knowing what altitude you are at and how to change your processing times based on this is an important aspect of home canning.
Your altitude is simply the height above sea level in which you are canning at. If you’re not sure what your altitude is a quick google search should be able to let you know.
In some of my recipes i provide a ‘processing time table’ which shows you the different processing times for different altitudes. If you are making one of my recipes that uses a processing time table and you are unsure how to read it then head over to my tutorial on reading processing time tables.
If you are making one of my recipes that does not have a processing time table and simply states ‘adjust for altitude’ then continue reading to find out how.
Why do you need to adjust for your altitude when canning?
It is important to adjust for your altitude because barometric pressure is reduced at high altitudes, meaning that it affects the temperature at which your water will boil.
This means that boiling-water and pressure processing canning methods must be adjusted to ensure the safety of home-canned foods. Additional processing time must be added when using the boiling water canning method and an increased temperature is required when using the pressure canning method.
My recipes that do not provide and processing time table are based on canning at an altitude of at or below 1000 feet above sea level. If you live at or below 1000 feet altitude then you can use the processing times that i state in my canning recipes.
However, if you live above 1000 feet above sea level then you must use the tables below to work out how much time or temperature to add onto the initial processing time.
Boiling Water Canning
The processing times that I give on my blog for high-acid foods are based on canning at or below 1000 feet above sea level using the boiling-water method. When processing times at altitudes higher than 1000 feet above seal level, adjust the processing time according to this boiling-water canner chart below.
|Boiling-Water Canner Altitude Adjustments|
|Altitude in feet||Increase processing time|
|1001 - 3000||5 minutes|
|3001 - 6000||10 minutes|
|6001 - 8000||15 minutes|
|8001 - 10000||20 minutes|
The pressure method is used for low-acid foods. There are two types of pressure canners currently available, weighted gauge and dial gauge. Refer to your canner instructions to determine which one yours is. It is possible to get a pressure canner that has both. When processing at altitudes higher than 1000 feet above sea level, adjust pounds pressure according to this pressure canner chart below.
|Pressure Canner Altitude Adjustments|
|Altitude in feet||Weighted gauge||Dial guage|
|0 - 1000||10||11|
|1001 - 2000||15||11|
|2001 - 4000||15||12|
|4001 - 6000||15||13|
|6001 - 8000||15||14|
|8001 - 10000||15||15|