Preserve it! Series: Canning Breads is Unsafe
Cake and quick bread should never be "canned."
Pretty pictures and recipes for quick breads and cakes canned or baked in canning jars (aka mason jars) often circulate on the Internet, especially around the holidays. Despite what some well-intentioned bloggers may say, the practice of canning breads and cakes in mason jars, either by conventional boiling water canning or “oven canning,” and then storing the jars at room temperature is unsafe.
Cake and quick bread recipes are usually low in acid and high in moisture. Together with creating a vacuum seal during canning (thus removing most of the oxygen), a perfect environment is created for some microorganisms to grow – including Clostridium botulinum, the pathogen responsible for forming the toxin that causes botulism. This pathogen requires very high heat to be destroyed, which cannot be obtained in a boiling water (or atmospheric steam) canner.
Low acid-high moisture is a dangerous combination
Oven canning, which is often used in these quick bread and cake recipes, is not a true canning method. Even if a seal is achieved, it may not be a good seal, and enough air could be left in the jar to allow oxygen-dependent microorganisms (such as mold) to grow. Also, the lids of poorly-sealed jars are known to come unsealed during storage. Putting a lid on a jar after the contents have cooled does not help either: the growth risk of C. botulinum may be eliminated, but air still gets trapped in the jar, allowing mold and other microorganisms to grow. Further, canning/mason jars are not tempered for the dry heat of an oven, and they could break. Putting these jars in a hot oven is not recommended.
There has been much research done to determine if there is a process for home-canning cakes and breads, and to date there is no recipe that is safe (and palatable). Therefore, these products should not be canned at home, via any canning method.
For further information on canning visit the National Center for Home Food Preservation (NCHFP) or contact your local Cooperative Extension office.
Brought to you by the UC Master Food Preservers of El Dorado County
Last updated July 2025