Clever Solutions for Common Canning Challenges

Foodborne illness or death can result from improperly home-canned food. Unfortunately, many unsafe canning recipes and practices are passed down from family or sourced online. While the recommendation to only follow research-tested recipes when canning may sound restrictive, there are safe ways to achieve the desired end product.

Safety Concerns

When canning food at home, only follow recipes that have been tested for safety in a laboratory. Obtain recipes from reputable sources such as the USDA or the National Center for Home Food Preservation. Safe recipes are included in Penn State Extension's "Let's Preserve" and "Preserving Food at Home" publications.

The biggest food safety concern is controlling the growth of the bacteria Clostridium botulinum in canned foods, which can cause botulism poisoning. This bacteria is difficult to control because it produces spores, which are like little survival pods, that are very heat-stable and require temperatures over 220°F to be destroyed. Water generally boils at a temperature too low for this, at 212°F.

Clostridium botulinum can be controlled in home canning in one of two ways: controlling acidity and/or ensuring the adequate transfer of heat. Some foods are naturally acidic including jam, jelly, fruit pie fillings, and sauerkraut. Other foods are acidified by the addition of an acid, such as vinegar when making pickles.

Testing recipes for safety includes careful measurement of the pH of the food being canned. The pH reflects the level of acidity. High-acid foods (with a pH of 4.6 or lower) may be safely canned using a boiling water bath. Low-acid foods (with a pH of 4.7 or higher) must be processed in a pressure canner.

Testing also measures how evenly heat is transferred throughout the canning jar during processing. Even heat transfer ensures there are no pockets of lower-temperature food inside the jar where illness-causing bacteria could survive processing. It is not possible to can thick foods at home because thorough heat transfer cannot be achieved.

Let’s look at a few common canning challenges and ideas to overcome them:

Pumpkin Pie Filling

Some people think that because canned pumpkin pie filling is sold at the grocery store that it may be safely canned at home. However, the conditions in a commercial processing facility cannot be replicated at home, even in a pressure canner. You cannot safely can pumpkin pie filling at home because it is too thick.

Solution

Homemade pumpkin puree can be safely frozen. Alternatively, cubes of pumpkin in water may be safely pressure canned. The water surrounding the cubes moves as it boils inside the jar, which enables even heat transfer. Then, just before baking, the jar is opened and the cubes are pureed. Extension's fact sheet, "Let's Preserve: Squash and Pumpkins," provides detailed directions on pressure canning pumpkin cubes.

Chicken Noodle Soup

Pasta cannot be included in foods canned at home because the starch slows the transfer of heat.

Solution

A chicken broth base with chunks of chicken and vegetables may be safely pressure canned. When you are ready to eat your soup, reheat the canned base and add noodles or pasta (cooked separately) before serving. Extension's fact sheet, "Let's Preserve: Soup," provides detailed directions for canning a chicken, vegetable, and broth soup base.

Creamy Tomato Soup

Some tomato soup recipes call for cream, milk, cheese, flour, or cornstarch. Those ingredients yield a deliciously creamy soup. However, those ingredients are unsafe for home canning because they are thickeners.

Solution

Can plain tomato sauce or tomato juice to use as the base for creamy tomato soup. Reheat the base and add the thickeners before serving. Canned tomato products require the addition of acid, like lemon juice, to ensure safety. Extension's fact sheet, "Let's Preserve: Tomatoes," provides detailed directions for canning tomato sauce and juice and their acidification.

Beef Stroganoff

Common ingredients include sour cream, butter, milk, flour, and noodles. It is not safe to can beef stroganoff because those ingredients are thickeners.

Solution

Hot-packed beef cubes may be safely pressure canned in broth. When you're ready to make beef stroganoff, use the canned beef; thicken the broth into a gravy; add sour cream, Dijon mustard and any other desired ingredients; and serve it over noodles. Penn State Extension's fact sheet, "Let's Preserve: Meat and Poultry," provides detailed canning directions for beef cubes.

Grandma's Tomato Sauce Recipe

Tomatoes are a borderline acidic food. Additional acid, such as bottled lemon juice, powdered citric acid or vinegar, must be added for safety.

Vegetables such as onions, mushrooms, carrots, and celery are low in acid. Adding those to tomatoes makes the resulting sauce less acidic. The proportion of ingredients in a tested recipe must be followed exactly to ensure the sauce remains acidic enough to be safely canned in a boiling water bath.

Solution

Follow a tested recipe that is either close to a family recipe or for plain tomato sauce, and add any additional ingredients when serving. A family tomato sauce recipe may also be safely frozen. Extension's fact sheet, "Let's Preserve: Tomatoes," provides detailed directions.

Meals in a Jar

Some people like the idea of canning an entire ready-to-eat meal in a jar that can be reheated with a minimum preparation time. Examples include casseroles, meat and vegetables in sauce, and other combination foods. These meals are often thick. When laboratory testing has not been performed on a specific combination of foods, it is unknown if sufficient heat transfer during processing is possible at home, and/or whether it is acidic enough to be safely canned in a boiling water bath.

Solution

Preserve individual foods at their peak freshness and use them as ingredients in the meals you prepare later. Use a pressure canner to can vegetables harvested from your garden or from the farmers market. The vegetables are cooked during canning and will only have to be reheated when making a meal, reducing the preparation time. Extension's fact sheets, "Let's Preserve: Root Vegetables," "Let's Preserve: Sweet Corn" and "Let's Preserve: Snap Beans," provide detailed directions for canning these common ingredients to use in meals.

Additional Resources

Copies of the "Preserving Food at Home Resource Guide," which includes tips for canning, drying, freezing, pickling, fermenting, and freeze-drying, as well as nutrition and storage information, are available online or by calling Customer Service at 877-345-0691. Penn State Extension also offers, at no cost, "Let's Preserve" fact sheets. If you have specific questions about preserving fruits, vegetables, and meats, you can call your local Extension office to speak with a food safety educator. Customer Service can provide the phone number for your local Penn State Extension office.

References

Bucknavage, M. & Cutter, C. (2025). Let's Preserve: Meat and Poultry. Penn State Extension.

Hirneisen, A., LaBorde, L., & Zepp, M. (2023). Let's Preserve: Root Vegetables – Beets, Carrots, Turnips, and Rutabagas. Penn State Extension.

Hirneisen, A., LaBorde, L., & Zepp, M. (2023). Let's Preserve: Snap Beans. Penn State Extension.

Hirneisen, A., LaBorde, & Zepp, M. (2023). Let's Preserve: Soup. Penn State Extension.

Hirneisen, A., LaBorde, L., Reed, S., & Zepp, M. (2023). Let's Preserve: Squash and Pumpkins. Penn State Extension. 

Hirneisen, A., LaBorde, & Zepp, M. (2023). Let's Preserve: Sweet Corn. Penn State Extension. 

Hirneisen, A., LaBorde, & Zepp, M. (2023). Let's Preserve: Tomatoes. Penn State Extension.