Are retort pouches safe for pressure canning?

Retort pouches, which are flexible and made of layered plastics and foil, are commonly used for pressure processing low acid foods in commercial canneries, but there are no researched techniques or recipes for safely using these pouches at home.

For safe canning of low acid foods like meats, seafood and vegetables at home, you should always use canning jars with two-piece lids, a pressure canner with an accurate gauge, and a researched process for pressure canning the specific food you are preserving. OSU Extension has many recipes available on our website.

The U.S. Food and Drug Administration has long approved of retort pouches for commercial canning. The pouches are arranged in very large pressure processing kettles, called retorts, and heated in controlled conditions to hotter-than-boiling temperatures required to kill bacterial spores and other pathogens.

Commercial canneries must use a processing time and recipe approved by a food scientist, and they keep detailed records on each batch that they produce. The commercial process of using retort pouches is safe because of the accurate and powerful temperature control achieved in the retort and the adequate spacing and circulation of heat around the pouches. Unfortunately, these same conditions aren’t possible in home pressure canners.

The home pressure canning process was researched by the U.S. Department of Agriculture to guarantee safe canning of low acid foods with equipment available to most home cooks. USDA and OSU Extension processing recipes assume the use of a standard home cooktop, a pressure canner large enough to hold four one-quart jars, an accurate gauge — either a dial gauge tested annually, or a weighted gauge — and standard canning jars with two-piece lids.

The use of standard jars is important to the safety of the process, because the circulation of steam heat around these jars is uniform and predictable. The USDA scientists conducting the research measure the length of time it takes for the coldest spot in a canning jar to reach the temperature required to kill pathogens using home kitchen equipment.

If you were to use retort pouches in a home canner, the circulation of heat around the pouches wouldn’t be the same as the commercial process. It would also be very different from the process tested by USDA for home canning in jars. You would have no guarantee that the temperature inside the pouch would reach the required 240 to 250 degrees Fahrenheit for the right amount of time, and the result could be an unsafe food. Improperly canned low acid foods are a leading cause of botulism poisoning in the United States.

Commercially processed foods in retort pouches are safe and convenient, but for safe home canning, stick with mason jars and tested procedures.

For more information on how to properly use a pressure canner at home, check out the Extension publication Use, Care, and Operation of Your Pressure Canner.