Fruit is typically a high-acid food that can be home-canned using the water-bath method.
Fruit chosen for canning as fruit should be at its peak in quality. Visual imperfections are fine, as long as they do not indicate a degradation in quality. The canning process won’t improve the quality of fruit. Above all, do not attempt to can mouldy fruit. The processing times might not be enough to sterilize the food properly, as they were developed assuming wholesome fruit. If you have a lot of bruised or blemished fruit, it is probably best suited for jam or other preserves after those imperfect bits are cut off.
If you have to delay canning fruit, if it’s at all possible to fit it all into your refrigerator, it’s best to do so, with the exception of fruit such as apples.
Directions for home-canning fruit typically call for a ½ inch (2 cm) headspace, but if a lab-tested recipe specifies otherwise, do what it says.
Fruit floating in jars after canning is a frequent complaint. Hot packing the fruit (see: Pack types for home canning) can alleviate this, but it will still sometimes occur anyway.
While it is true that tomatoes botanically are fruit, they are of course treated as a vegetable, and an entirely separate sub-set of home canning directions have been created for them. (See: Canning tomatoes)
Peeling fruits for home canning
If a lab-tested home canning recipe for a given fruit directs you to peel the fruit, then you need to do that. The skin of produce can host bacteria that the recipes methodology and processing times are counting on you having removed by peeling.
To paraphrase what the The National Center for Home Food Preservation says about tomatoes:
“Peeling… may seem like an unimportant extra step, but the texture of the skin was determined to be undesirable and product testing did not include considerations of how the skin would alter the final product safety. So… peel… as described in the procedure. Our canning recommendations are meant to be followed as written, since that is how they were developed and changing ingredients or steps may influence not only the quality but also the safety of the final product.” [1]National Center for Home Food Preservation. Preserving Food at Home Blog. Try It: Tomato Jam. 19 August 2015.
Wash the fruit before peeling, so that the act of peeling doesn’t drive surface bacteria into the flesh.
Peeling can seem like a thankless chore, but there are a few tricks to make it a bit easier. The Ball / Bernardin Complete Book offers a couple:
“To peel fruits such as peaches and apricots, place them in a pot of boiling water for 30 to 60 seconds or until the skins start to crack. Immediately dip in cold water. The skins will slip off easily.” [2]Kingry, Judi and Lauren Devine. Ball / Bernardin Complete Book of Home Preserving. Toronto: Robert Rose. 2015. Page 140.
Typically, canning directions for smaller fruit such as berries, cherries or grapes are developed for them unpeeled.
When some fruit being canned is not peeled, such as plums or whole crabapples, directions will typically call for the fruit to be pricked with a fork to allow air out to prevent the fruit bursting.
Pack type choices for fruit
For good quality home canned fruit, the pack type is more important than the type of canning liquid. “Pack” refers to the way fruit is prepared and placed in a container preparatory to canning.
The pack type choices are raw pack, or hot pack. Raw pack is faster. The fruit is washed, and sometimes peeled, cut and seeded as well, but not heated. A hot pack takes more time, as the prepared fruit is also heated before being packed into the jars, but it drives air out of the fruit which otherwise can lead to faster degradation of quality on the shelf.
Every single canning authority advises that hot pack of home canned fruit is typically a better choice than a raw pack.
Bernardin says that hot pack is superior:
“Fruit has very porous tissues. While these pores contain the juice we love, they also hold air that, if not exhausted from the fruit, can cause discolouration as well as floatation. Hot packing fruit helps exhaust this air. Hot packing requires prepared fruit to be heated to a boil in the hot canning liquid. Raw packing skips this step and often results in an inferior product. One of the goals of home canning is the removal of excess air… [this] also prevents fruit from floating to the top of the jar, increases the vacuum in sealed jars and improves shelf-life.” [3] Bernardin Guide to Home Preserving. Toronto, Canada: Bernardin Ltd. 2013. Page 36.
Still, raw pack is conceded as a valid choice in a few rare cases for “more delicate fruit” that would not survive initial simmering in water to heat it: [4]Ball Canning Back to Basics. New York: Oxmoor House. 2017. Page 96. for instance, very soft berries.
The Ball / Bernardin Complete says:
“Use the raw-pack method for red and black raspberries and other berries, such as blackberries, that don’t hold their shape well when heated. Use the hot-pack method for firmer berries, such as blueberries, currants, elderberries, gooseberries and buckleberries.” [5]Kingry, Judi and Lauren Devine. Ball / Bernardin Complete Book of Home Preserving. Toronto: Robert Rose. 2015. Page 146 [6][Note 2022: do not attempt to home can elderberries. It’s been realized since the above was written in 2015 that some varieties can be lower in acid, and testing is required to ascertain safe acidification levels. (For what it’s worth, note they don’t include strawberries in the list of soft berries for which they suggest a raw pack.)
A sugar syrup is required for the raw pack of any fruit. Water or juice are not options when raw packing. The raw pack method must always be accompanied by a sugar syrup. [7] Bernardin Guide to Home Preserving. Toronto, Canada: Bernardin Ltd. 2013. Page 37.
For some fruits, such as whole berries, the processing time may be longer for raw pack than it would be for hot pack. [8] See whole berries at NCHFP
For a deeper discussion, see: Pack Types for Home Canning.
University of Georgia video
Pressure canning versus water bathing home canned fruits
All home canned fruits from which there are lab-tested recipes can be safely water-bathed, with the right directions.
Some may optionally be pressure canned using special directions for pressure canning.
The Presto manual says,
“Fruits may be safely processed using the boiling water method. However, you may use, and some prefer, the pressure canning method.” [9] Pressure Canning: Canning Fruits. Presto. Accessed March 2015 at https://www.gopresto.com/content/canning/canning-fruits
The USDA gives guidelines for pressure canning apples, applesauce, apricots, berries (except strawberries), cherries, grapefruit, nectarines, oranges, peaches, pears, plums, and rhubarb. [10] United States Department of Agriculture (USDA). Complete guide to home canning. Agriculture information bulletin No. 539. 2015. pp 2-31 to 2-32
Some people feel that a pressure canning process cooks fruits (other than perhaps apples or peaches) to smithereens, particularly people who live 300 metres (1000 feet) above sea level, and are therefore required to run at higher pressures. For those at sea level and less than 300 metres (1000 feet), the pressure required is only 5 pounds.
Pressure canning fruit does not deliver any safety advantages over water bathing. The safety comes from the acidity of the fruit and normal heat processing. The pressure canning process is simply an accelerated equivalent of the water bathing: compare processing times of apple slices at 20 minutes in a boiling-water bath, versus 8 minutes in a pressure canner. However, there’s also heat-up and cool-down times to be taken into account, which could easily evaporate any time savings.
Special procedures for low-acid fruits
Low-acid fruits require special handling, regardless of whether there is added sugar or not. It is the acidity of the fruit that makes fruit safe for canning; not the sugar.
Some low-acid fruits, such as melons (including cantaloupe and watermelon) cannot be canned safely on their own, ever, as no safe, tested procedures have been developed for them. The University of California says,
“Cantaloupe and other melons should not be canned. Cantaloupe and other melons are nonacidic (have a high pH), with pH values ranging from 6.1 to 6.6. Nonacidic canned fruits support the growth to the bacterium that causes botulism when given the right conditions, which include moisture, room temperatures, lack of oxygen, and low-acid conditions. The high pH means that the product would need to be canned using a pressure canner rather than a water bath canner to ensure product safety. Safe processing times have not been determined because the high temperatures that would be needed leave the melon mushy and inedible. Cantaloup preserves or pickle recipes from reliable sources can be safely processed using a water bath canner because the addition of acids or acidic ingredients safely lowers the pH… Do not alter the proportion of fruit to lemon juice or other acids such as vinegar in preserve or pickle recipes containing cantaloupe [Ed: or any melon].” [11] Parnell, Tracy L. et al. Cantaloupe: Safe Methods to Store, Preserve, and Enjoy. University of California, Division of Agriculture and Natural Resources. Publication 8095. 2003. Page 3 – 4. Accessed March 2015 at http://anrcatalog.ucdavis.edu/pdf/8095.pdf .
Note particularly that people have got botulism from watermelon jelly made using home-made guesswork recipes. As of 2022, we know of only a few lab-tested recipes for a melon jam or jelly, which are Melon Jam in the Ball All New Book (2016), page 44 and Zesty Watermelon Jelly in the Ball / Bernardin Complete (2015), page 117. The Ball Blue Book and the Ball / Bernardin Complete also have safe, tested recipes for melon and watermelon rind pickle.
Other low-acid fruits include Asian pears, banana, coconut, figs, ripe mango and papaya. They cannot be safely canned on their own. They need to be used in lab-tested recipes which have enough added acid to make them safe.
For instance, special procedures have been developed for the home canning of Asian Pears and figs on their own, which require the packing liquid be acidified enough to make them safe:
“Guidelines for acidification and water bathing of Asian Pears and figs were added to the USDA guide based on work done by researchers Woodburn, Raab, Hilderbrand at Oregon State.” [12] Andress, Elizabeth. “History, Science and Current Practice in Home Food Preservation.” Webinar. 27 February 2013. Accessed January 2015 at https://nchfp.uga.edu/multimedia/video/nchfp.wmv
Do not attempt to home can elderberries. It’s been realized that some varieties can be lower in acid, and research testing is still required as of 2022 to ascertain safe acidification levels.
Do not attempt to home can white peaches for the same reason.
See also: Home-Canning Low Acid Fruits
Canning fruit topics
Approximate Yields for Canned Fruits
Canning liquids for fruit
Home canning fruit sugar-free
Home-canning low-acid fruits
References