Tips for Preserving Vegetables and Making Homemade Jam

In this guide, you will find proven tips for preserving vegetables and making homemade jam. It covers the correct selection and pasteurization of jars, safe use of lids, and simple recipes for plum jam and pickled peppers.

Cleaning Jars and Lids and Pasteurization

Before preserving vegetables or preparing jam, it is essential to use suitable jars and lids. Glass is an excellent reusable material, so previously used jars can be washed and reused for food storage. It is important to check that the jars are not physically damaged, cracked, or chipped.

Lids are generally intended for single use. Although reusing them may sometimes work, there is a risk that the sealing compound on the inside of the lid has aged and hardened. This can result in improper sealing of the jar. In addition, lids may become deformed if they have been attached to jars in storage for a long time, which prevents reliable food preservation.

Jars and lids are not sterile and must be washed and pasteurized before use. The Slovenian National Institute of Public Health (NIJZ) recommends washing jars and lids in a dishwasher and then heating them in an oven at a temperature of at least 100 °C for a few minutes, or boiling them in water for approximately 10 minutes.

How to Preserve Food Properly at Home

The choice of recipe for preserving vegetables or making jam is left to the individual. Recipes can be taken from cookbooks, online sources, or traditional family recipes. Below are two recipes adapted from the book Recepti sestre Nikoline.

Plum Jam

Ingredients

  • 1 kg plums
  • 300 g sugar

Preparation method
Remove the pits from ripe plums and soften them by steaming them in their own juice. Then mash the plums, add sugar, and slowly cook the mixture for about one and a half hours until the desired thickness is achieved. During cooking, stir the jam regularly and ensure cleanliness and good hygiene to prevent contamination with microorganisms [1].

Filling the Jars

Pour the hot plum jam into preheated jars, filling them to about 1 cm below the rim. As the jars cool, a vacuum forms, visible as the lid button being pulled inward or the lid bending downward.
The rim of the jar must be clean and dry, so any jam residue should be wiped off with a paper towel to ensure proper sealing.

Close the jar using moderate hand pressure – using three fingers. Excessive force may cause the lid to slip and prevent further proper sealing. Cover the closed jars and allow them to cool slowly, then store them in a cool, dark pantry.

Jars can also be labeled with stickers showing plums, peaches, apricots, etc. Such labels are available from our company and allow you to note the type of fruit as well as the month and year of production.

Pickled Peppers – A Homemade Preserving Recipe

  • Ingredients
  • 5 kg peppers
  • 2 l pickling vinegar
  • 4 l water
  • 70 g salt
  • 200 g sugar
  • bay leaves
  • whole peppercorns

Preparation method
Bring all ingredients except the peppers to a boil in a large pot. Add the cleaned and halved peppers to the hot liquid and cook them for about two minutes, until they soften slightly and change color. Remove the peppers from the liquid and arrange them in jars. Evenly pour the remaining liquid over the peppers [1].

Sealing and Storage

The peppers must be completely submerged in the liquid. If necessary, canning nets can be used to keep the vegetables below the surface. At Avacom, we have been producing and selling such canning grids for almost 40 years. They are placed on top of the preserved vegetables with the legs facing upward and push the vegetables under the liquid when the jar is closed.

Fill the jars to approximately 1 cm below the rim and make sure the rim is dry, wiping it with a paper towel if necessary.
Seal the jars immediately after filling, cover them, and allow them to cool slowly. Close the lids using moderate hand pressure – with three fingers – as excessive force may damage the lid.

Once cooled, store the preserved food in a cool, dark pantry. The jars can be labeled with the contents and the date of preserving – AVACOM offers attractive labeling stickers for this purpose.

[1] N. Rop (2021): Recepti sestre Nikoline. Družina