PETE (polyethylene terephthalate) plastic containers are a good option for dry packing dry foods for food storage. The plastic blocks 99.9% of oxygen transfer thus protecting the food from oxidation once the oxygen in the container is removed. PETE containers are also often “free.”
PETE containers used for dry packing (and for water storage) are typically recycled juice bottles, large water bottles, and carbonated drink bottles. There are, however, PETE containers used for other foods. Applesauce, peanut butter, and mayonnaise are three of those foods.
I wrote about using PETE applesauce jars for dry packing last December. (See “Dry Packing in Applesauce Jars) Peanut butter jars cannot be used for dry packing because the lid is not airtight. It doesn’t have the soft rubbery compound (plastisol) around the inside of the lid that makes it water and airtight. Instead, a piece of plastic or foil covered cardboard is sealed to the jar before the lid is put on. Mayonnaise is packaged in the same kind of containers with the same kind of lids.
Mayonnaise jars are different from peanut butter jars in one significant way – a canning lid and ring will fit on them. When I realized that, I wondered if PETE mayonnaise jars could be used for dry packing. I wanted to find out.
I made sure my empty mayonnaise jar was cleaned well, especially the rim. Then, I made sure the canning lid and ring would screw on tightly. I filled the jar with rice and a 100cc oxygen absorber. The canning lid was warmed in hot water to soften the sealing compound, thoroughly dried, and put on the jar with the ring. I then let the jar sit. And sit. And sit while I waited for the lid to seal.
The jar never sealed. I suspect that the problem is the rim of the jar. It’s not smooth like a glass jar and probably leaks. It was worth a try but now we know. Sadly, PETE mayonnaise jars are not an option for dry packing dry foods for food storage.
(BTW, don’t get rid of those peanut butter jars! They make great gift containers for soup mixes!)
