Jam and marmalade
Jam/marmalade is berries or fruit (whole or in small bites) boiled with sugar.
Marmalade has a firmer texture and is more or less jelly-like. The texture of the jam/marmalade is affected by pectin, sugar, acid and water. In home-made products, pectin, acid and sugar come from the fruit. In the food industry, the composition is regulated by adding extra pectin and fruit acid.
Under the EU fruit jams, jellies and marmalade directive, and subject to certain exceptions, a berry content of at least 35% is required for a manufacturer to be allowed to call a product jam. For products labelled "extra jam" or "extra prima" the requirement is a berry content of at least 45%. Formerly it was an EU requirement that the sugar content in jam was at least 60% if the product was intended for export.
Sugar has an impact on
Taste – sugar adds sweetness and enhances, preserves and balances the natural taste and flavour of fruit/berries.
Texture – sugar can combine with pectin and acids in fruit and berries to form a jelly. Often extra pectin and fruit acid must be added to achieve the right texture.
Colour – the fruit maintains its colour because the sugar prevents it from absorbing water.
Keeping qualities – sugar binds water and thus prevents the growth of microorganisms.
Fruit and berries have a certain natural sugar content – equivalent to 3-20%. Sugar is added in the manufacturing process, so the sugar content in jam and marmalade is typically 45%.