MU Extension MU Extension       University of Missouri    ●    Columbia    ●    Kansas City       Rolla     ●    St. Louis - Food Safety


Quick Answers



I prefer strawberry jam made in the microwave. How long can these spreads (including the butter) be kept in the refrigerator/freezer. What kinds of directions should I give if I give these as gifts?

These refrigerator/freezer jams have a very long shelf-life. Frozen, it would be almost indefinite. In the refrigerator, you would be limited only by mold or yeast growth - neither of which would be harmful but might make the jam taste a bit “funny.”

For gifts, I would recommend that you give the product frozen, with an instruction card that states something like:

“To preserve the delicate flavor of this homemade jam (syrup), please store refrigerated. Product stored in the refrigerator should be consumed within a few weeks. For longer storage, you can freeze the jam (syrup). Discard if any mold appears on the surface.”

As far as I know, you do not significantly change the acid level in a fruit by pureeing it. The acid level in reasonably ripe fruit is sufficient that only spoilage microorganisms will grow. By adding sugar, you make it even more difficult for any microorganisms to grow. The butter you add will not change the safety characteristics of the final product very much. By heating, you kill even more microorganisms. So if you take care to use good sanitation during processing, put the product in clean containers and seal promptly, store frozen or keep refrigerated, you should get several months of high quality product from your efforts.


Source: Douglas Holt, Ph.D., Chair of Food Science Program & State Extension Specialist for Food Safety, University of Missouri-Columbia






Last update: Tuesday, May 05, 2009



University of Missouri logo links to

Site Administrator:
Copyright  ADA  Equal Opportunity

MissouriFamilies is produced by the College of Human Environmental Sciences,
Extension Division, University of Missouri