In order for a gel to happen with jams and jellies, acidity, pectin and sugar must be present. The USDA Complete Guide to Home Canning says, “For proper texture, jellied fruit products require the correct combination of fruit, pectin, acid, and sugar. The fruit gives each spread its unique flavor and color. It also supplies the water to dissolve the rest of the necessary ingredients and furnishes some or all of the pectin and acid.” United States Department of Agriculture (USDA). Complete guide to home canning. Agriculture information bulletin No. 539. 2015. Page 1-29.
Some varieties also contain sorbic acid to help act as a preservative for the preserve you are making.
Low-carb and sugar-free varieties are also available now, using replacements such as erythritol and powdered stevia for the sweetness. (See here for more information on sugar-free jams and marmalades. We have not seen the ingredient list for these products, but it may be that they use a low-methoxyl pectin, which allows a gel to occur even in the absence of actual sugar.
Do not use it in jam or jelly recipes that call for sugar and pectin to be added separately.
Where is jam sugar used
Jam sugar is primarily used in Europe and places such as South Africa, Australia and New Zealand. In North America, most home preserving recipes are written for pectin being added separately to the recipe.
Occasionally, you may see it in the U.S. or Canada. If you come across a jam recipe calling for jam sugar where it is not said, then really the best course of action is to look for another recipe that calls for sugar and pectin to be added separately. Two good sources of such recipes will be the jams sections of the National Center for Home Food Preservation, as well as of course of our satellite site, Healthy Canning.
Jam sugar ratio numbers
Some jam sugars will have ratio numbers on them. Most German jam sugars do; Tate and Lyle sells a jam sugar labelled “1:1” (as of 2020.)
The ratio numbers indicate the proportion of fruit to jam sugar you should use.
- 1:1 – For recipes with equal weights of fruit and jam sugar;
- 2:1 – For recipes with twice as much fruit by weight as jam sugar;
- 3:1 – For recipes with three times as much fruit by weight as jam sugar;
Some jam sugars will be sold with no ratio numbers on the package; in that case, follow directions that will be on the package.
Note that (as of 2020) the manufacturer Dan Sukker also makes, in addition to their jam sugars, a sugar specifically labelled separately as “jelly sugar”:
“Fruit tarts with decorative jelly, mousse, pannacotta and pudding – now you can quickly and easily make all of these yourself. Jelly Sugar Multi can be used to make jelly itself or e.g. pannacotta. The product contains only vegetable gelling agent, which means that it can be used for a vast range of desserts where you would otherwise have to add gelatine. Jelly Sugar Multi gives good consistency together with water, fruit juices and dairy products – simple and convenient to use! Accessed July 2020 at https://www.dansukker.co.uk/uk/products/all-products/jelly-sugar-multi.aspx
Jam sugar has a shorter storage life than regular sugar owing to the added pectin and citric acid.