Preserving Jam Without Sugar – That’s How it Works

Jam without sugar – long-lasting with the right fruit

If you use sweet fruits, the high fructose content ensures a long shelf life.

• You don’t need any sugar to make long-life jam from plums or mirabelle plums.
• To do this, however, you have to cook the fruit for a long time. Washed and chopped up, the fruit is then placed in a pot and boiled until the fruit has boiled down to a spreadable mass.
• That takes time: with one kilogram of fruit, you have to reckon with a cooking time of around ten hours.
• The fructose is then so concentrated that you don’t have to add any more sugar.

Alcohol protects the food

In the past, neither screw-top jars nor jars were used. Still, the jam didn’t go bad.

• You don’t even need a sealable jar for your homemade jam. In earlier times, only cellophane was stretched over the edge of the glass with a rubber band.
• Nevertheless, the shelf life of the jam was not limited. The reason for this is a simple trick: a piece of cellophane the size of glass is dipped in high-proof alcohol – rum works well here – and placed directly on the surface of the jam.
• If this alcohol film covers the entire surface, germs and mold don’t stand a chance. It is important that the jam is filled hot into boiled jars and covered directly with the alcohol foil.
• In addition, the film should be pulled tightly and wrinkle-free over the edge of the glass immediately after filling and fixed securely with a rubber band.
• When the jam cools down, a negative pressure forms in the jar. You can tell by the fact that the foil curves down a little. The negative pressure also ensures that the jam has a longer shelf life.