Holiday baking is a staple for many gift givers, but bread makers should take caution: Making bread in canning jars creates a readymade package, but poses life-threatening risks.

According to the National Center for Home Food Preservation, some bread and cake recipes call for baking in canning jars and then closing with a canning lid. However, these recipes have very little or no acid, providing the perfect habitat for the growth of Clostridium botulinum and its toxin that causes botulism poisoning. Botulism is a sometimes fatal foodborne illness that paralyzes muscles, including respiratory muscles.

“When breads and cakes in jars are made for sale commercially by reputable companies, additives, preservatives and processing controls (that are) not available for home recipes are used,” according to University Extension Food Specialists from the University of Georgia. “Safety tests would have been conducted for each specific recipe for commercial products.”

The National Center for Home Food Preservation also reminds consumers that canning jar manufacturers do not endorse baking in their canning jars, for a variety of reasons.

Additionally, there is a risk of consuming broken glass from bread and cakes baked jars. Since canning jars are intended for use with moist heat, in boiling water baths or pressure canners, they are not made to withstand the “thermal stresses” that dry oven heat inflicts during baking.

The UGA Extension report concluded that because “no reliable, safe recipes for baking and sealing cakes or breads in jars for room temperature storage are available to the home cook, it is best to say these products are not recommended at this time.”

Also, frozen recipes should always be chosen over their room-temperature counterparts to help eliminate the growth of dangerous bacteria. Kick the canning jars to the curb and keep freshly baked bread and cakes a food safe gift this season of giving.

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