I have read that drying oil and storing it without refrigeration is not safe. I have a recipe to dehydrate tomato sauce and add it to a dehydrated meal. The person who provides the recipe says it is OK to dehydrate the tiny amount of olive oil in the sauce. Is that true? Will a tiny amount of olive oil go rancid in a dehydrated meal? If so, how long. Would it keep for 1 month?
The small amount of oil in a tomato sauce should be safe to dry and store for a few weeks. Rancidity results when oils react with air/oxygen. The process of drying, which involves lots of air flow, speeds up the likelihood of that happening. Rancidity isn't immediately unsafe, but results in a change in flavor. The tomato sauce may mask the flavor change. There is ongoing research into the long term impacts of consuming significant quantities of rancid oils, but no clear answers yet.
To slow any flavor changes as much as possible, use up the dried tomato sauce on a timely basis and store it in a sealed package and cool place to slow any further quality changes after drying.