What’s Your Elevation? Does It Matter?

While residents of most Midwestern States usually don’t think about their elevation, elevation affects cooking and baking as well as home canning.  As elevation rises, air pressure falls and water boils at lower temperatures.

Boiling water at 1014 Ft of elevation

When it comes to everyday cooking and baking, there are few noticeable effects of elevation until one reaches 3000 ft.  Higher altitudes present several challenges when preparing some foods. At higher altitudes, leavened products using yeast, baking powder/soda, egg whites, or steam rise more rapidly, may collapse, and may not be fully cooked. Because water boils at a lower temperature at higher elevations, foods that are prepared by boiling or simmering will cook at a lower temperature, and it will take longer to cook. High altitude areas are also prone to low humidity, which can cause the moisture in foods to evaporate more quickly during cooking. At altitudes above 3,000 feet, preparation of food may require changes in time, temperature or recipe.  For those that find themselves at higher elevations, Colorado State University and New Mexico State University have excellent tips and guidelines for successful baking and cooking.

Because water boils at 212°F at sea level and decreases about 1°F for each 500-ft increase in altitude, adjustments must be made when canning foods at home to ensure home-canned foods are processed safely. The amount of time that jars are held at a certain temperature during canning is important to producing a safe product. Processing times for most recipes are based on elevations of 0-1000 ft unless stated otherwise. When elevations are above 1000 ft, extra time is added for food processed in a water-bath canner.  For food processed in a pressure canner, extra pressure is added.  Both adjustments are needed to get to their respective safe processing temperatures for high acid and low acid foods. 

Each USDA process has an altitude table with it. In this example for Crushed Tomatoes from the USDA Compete Guide to Home Canning, 2015 edition, note that time is increased in 5 minute increments as altitude increases for boiling water canning and pounds of pressure is increased for pressure canning. (Crushed Tomatoes is one example a food that can be processed by either boiling-water bath or pressure.)

While time is adjusted for water-bath canning, pressure regulation differs by the type of pressure canning equipment used—dial- or weighted-gauge canner as noted in the chart. (To be considered a pressure canner, the USDA recommends that a canner be large enough to hold at least 4 quart jars.) Pressure canners have either a dial gauge to indicate the pressure or a weighted gauge to indicate and regulate the pressure. Weighted gauges are designed to “jiggle” several times a minute or to rock gently when they are maintaining the correct pressure. If a dial-gauge canner is used, the gauge needs to be checked each year for accuracy.  If the gauge reads high or low by more than two pounds at 5, 10 or 15 pounds pressure, it should be replaced. If it is less than two pounds off in accuracy, adjustments can be made to be sure you have the required pressure in your canner [NCHFP]. Gauge testing is available at some county extension offices; contact your local extension office for testing availability. See Testing dial pressure canner gauges for more information [University of Minnesota Extension].

Elevation does matter in all aspects of food preparation, but especially so in home canning. Before beginning the canning process, it should be a priority to find and know your elevation.  It is quite easy to find your elevation using one of these sources:

  1. Visit a web page about your town or city;
  2. Use an online tool such as https://whatismyelevation.com;
  3. Use a smartphone app such as My Elevation;
  4. Refer to an elevation map for your state showing approximate elevations such as this one by Iowa State University Extension and Outreach from the Preserve the Taste of Summer series.

To learn more about elevation, watch this YouTube video by UnL Extension Food & Fitness.

To learn more about safe water-bath or pressure canning practices, watch these videos produced by South Dakota State University:

How to Use a Water Bath Canner video
How to Use a Pressure Canner video

Marlene Geiger

I am a graduate of the University of Nebraska-Lincoln with a BS in Home Economics Education and Extension and from Colorado State University with a MS in Textiles and Clothing. I enjoy spending time with family and friends, gardening, quilting, cooking, sewing, and sharing knowledge and experience with others.

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