Canning:  preserving the harvest

courtesy of Colleen Joice, P.Dt

Long sunny days, cool evening breezes and night time showers are characteristic of Nova Scotia summers and provide the perfect climate that fosters our rich agriculture heritage. Farms and fields are busy as vegetable and berry plots emerge from our rich Nova Scotia soil.1


Summer and fall is a time to eat fresh and to think about how best to preserve the goodness of our fields and orchards and to enjoy the freshness of our bountiful harvest throughout the remainder of the year. The idea of extending the availability of vegetables and fruits throughout the year, beyond their season, is a perfect fit with the eat local movement that is becoming part of our Nova Scotia lifestyle.


So, how can we best preserve the harvest? Looking back into our Nova Scotia history, canning has long been a method of food preservation that is linked to our heritage and traditions. Canning is a skill, which can easily be performed in the home kitchen. However home canners need to recognize that canning is a scientific process and that a safe and high quality outcome depends on following a set of definite procedures. Furthermore, in recent years, standard canning procedures have become stricter to prevent episodes of food borne illness. So let’s take a look at home canning from the perspective of safety, enjoyment and a means of providing vegetables and fruits to our families throughout the whole year!


First of all, home canners need to understand the two different methods of canning;


1.  Boiling Water Bath Canning

  • Suited for high acid foods like fruits and tomatoes, pickles, relishes, jams and jellies.

  • Temperature in the canner as the water boils is 100 o C and is high enough to kill bacteria, yeasts and molds.


2.  Pressure Canning

  • Suited for low acid foods like vegetables.

  • Temperature in the pressurized canner is 116 o C and is high enough to kill the spores of the Clostridia Botulism bacteria.


Clostridium botulism spores


Can grow in low acid foods like vegetables, they do not grow on high acid foods like fruits and tomatoes.

Are destroyed by heat that reaches a higher temperature in a pressure canner (116 o C).





The boiling water bath process

  • Kills spoilage organisms such as bacteria, yeasts and molds.

  • Drives the air out of the canning jars to create an airtight seal. This airtight seal keeps both the air and bacteria from re-entering the jar.



Every recipe has its own canning time. Canning time is measured after the water in the boiling water bath comes to a boil over the jars. Even the difference of one minute could cause the food to spoil.


*Larger jars need more time in the boiling water bath

*Each fruit and tomatoes have their own canning time, this will be included as part of the recipe.





Canning supplies are available at hardware stores or grocery stores.  Some of the equipment, like the jars and screw bands, may be used from year to year, only the canning lid needs to be replaced.


Boiling Water Bath Canner

Non-metallic Funnel

Tongs to lift jars

Canning jars

2 cups (500 mL) or 4 cups (1 L) size

Canning lids and

Screw bands for lids



If you are new to canning, it is easiest to think of it as following a series of steps:


  • Find a recipe. Many of our best recipes are the ones that have been handed down from family or friends, assemble your equipment and ingredients. Measure dry ingredients and prepare the fruit or tomatoes.


  • Fill the home canner with fresh water and heat it. It will take longer than you think to come to a boil!


  • Check all the canning jars for nicks, cracks, uneven rims or sharp edges that may prevent sealing or cause breakage.   Wash jars (even if new) and place on a rack in a boiling water canner.  Cover jars with water heat water to simmer.  Keep jars hot until ready to use.


  • Set screw caps aside, place the canning LIDS in small pot of hot but not boiling water.


  • Set up an area close to the canner as your  "filling station", and have your funnel, ladle, paper towels, tongs and screw bands ready.   Fill jars, top with a lid and screw band.  Once the water comes to a full boil start to measure the time.


  • Set up an area close to the canner as your  "resting station", and set clean tea towels in a place near the canner. Once the time is up, transfer the jars to the towels. Let the jars rest, undisturbed, for 24 hours.


  • Check all the lids for a safe and airtight seal.  The lid should be pulled down into the jar or concave in appearance and does not move when pressed in the middle. Jars that do not seal properly should be placed in the refrigerator and eaten as soon as possible.


It is important to recognize all the steps of the Boiling Water Bath method of canning.  Unfortunately, not all home canners recognize all the steps and many people still follow ‘the open kettle’ method of canning, which involves putting hot food into sterilized jars without immersing the jars into the boiling water bath. Many years ago, it was commonly used for pickles, jams and jellies, and sometimes used for tomatoes and applesauce.  Open kettle canning is not recommended, as the food is not heated adequately to destroy the spoilage organisms, molds and yeasts that can enter the jar while you are filling the jar, and it does not produce a safe airtight seal on the jar.


So have fun putting the harvest away to savour and enjoy during the cold winter months! For further information the following links may be helpful:


1 A Cookbook for Families, Adapted from Strive for Five at School!  2013. Annapolis Valley Health, Public Health Services.

Our blog this week is provided courtesy of Colleen Joice. Colleen is a Nutrition Consultant living in Nova Scotia.  Colleen received a Bachelor of Science with a Major in Dietetics from McDonald College of McGill University in 1974.  In 1996 she completed a postgraduate Certificate in Adult and Continuing Education from the University of Manitoba. She is currently a member of the Nova Scotia Dietetic Association.  


Colleen has done extensive recipe, cookbook and workshop development along with train the trainer facilitator guides for various programs including the projects Strive for Five and Goodness in Many Ways. She has lead many people through workshops to teach cooking skills and share her passion and knowledge for food and food culture.  Colleen also instructed in the School of Nutrition at Acadia University from 1997 through 2001.  


Colleen had the opportunity to live in Europe for many years.   This experience has fueled her passion and knowledge of food and food culture.  Participation in European food preparation classes has enhanced the value that she places on the availability, preparation, consumption and enjoyment of whole foods.  



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