Ask The County Agent: Is the Water Bath Method okay to can green beans?

Photo Credit: Georgia Grown

Olivia Handley

By OLIVIA HANDLEY, Family and Consumer Sciences Agent, Coweta County Cooperative Extension

Question: Can I use the water bath method to can my green beans?

Agent: Great question and a very important topic in food processing safety – which foods can be water bathed and which foods need to be pressure canned? The quick answer to the question is, No. You cannot water bath process green beans, and it doesn’t matter how long your recipe calls for, they’re not going to be safe to eat. Let’s look at the reasons why.

Certain foods are perfectly fine using the water bath method of canning. This method is putting food into jars and then the jars into a large pot of water until they are covered by at least one inch over the tops of the jars and the water is brought to a hard boil for a set time. A rack is needed on the bottom of the pot to prevent breakage as the jars are boiled. During this water bath, the food inside the jar is heated to a temperature of 212°F. Then the jars are removed and allowed to cool at room temperature for 12 to 24 hours before the seals are tested. This process creates a vacuum seal that keeps moisture in and contaminants out.

This method of canning is acceptable for jams, jellies, and preserves which have a high sugar content. The sugar content helps to preserve the food and inhibits bacterial growth. It is also acceptable for acidified foods such as pickles or salsas which have an added acid (5% vinegar, bottled lemon juice, or citric acid) which can lower the acidity to a level that inhibits bacterial growth. Acid foods, like most fruits, can also be canned in a water bath. The acidity of tomatoes is borderline, and the addition of acid allows them to be safely canned using a water bath canner.

All other low-acid foods need to be pressure canned. This includes vegetables, meats and seafoods. Pressure canning involves a different type of canner which can be sealed up to increase the internal temperature above the boiling point of water. Pressure canners can be dial gauges or weighted gauges. The jars are added to the canner, and it is sealed up. Once the canner is under pressure to a certain level, the timing of the recipe starts. The internal temperature of a pressure canner can reach 240° -250°F (10-15 pounds of pressure at sea level). This is the only way that foods are heated to a high enough temperature to destroy harmful bacteria.

Therefore, given that green beans are a low-acid food, they must be pressure canned. No matter how long they are in a water bath canner, the temperature will never get above 212°F. The exception to water bath canning green beans would be to pickle the beans, therefore making them an acidified food. And then they could be processed in a water bath canner.

Beware of online recipes from sources that are not research-based. The last thing you would want is to get sick from a bad recipe or even simply lose the food because it spoiled, and you had to throw it out. Make sure you are using tested and approved recipes from reputable sources.

The National Center for Home Food Preservation is a great resource for all the home preservation methods and recipes. Happy canning and eat safe!!

For more information on canning or home food preservation, visit or contact the Coweta County Extension office at 770-254-2620.

The University of Georgia College of Agricultural & Environmental Sciences is an equal opportunity, affirmative action organization.

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