Recently there have been press reports about an EU regulation which stipulates a sugar content ratio of 60g per 100g in jam. The regulation refers to jam that is made using fruit, sugar and water or fruit and sugar.
“The Regulations require as a general rule that jam, extra jam, jelly, extra jelly, marmalade, jelly marmalade and sweetened chestnut puree have a sugars content (expressed as soluble dry matter content) of at least 60%.” They also state that “ For products labelled as “reduced sugar”: the product must have a soluble dry matter content of not less than 25%, and not more than 50%.” (1)
In Denmark, France and Germany, the regulation is not enforced and jam with a ratio of 55g per 100g is sold.
The role of sugar in jam should not be seen as merely about the ratio. In the UK the 60g per 100g EU regulation has its origins in the UK as far back as the 1920s. As part of their work during that decade, researchers at Long Ashton Research Station, Bristol investigated the role of sugar in prolonging the shelf-life of jam. The recommendation was 60% sugar to 40% fruit for jam made in a domestic kitchen.
It is the correct proportions of pectin, acid and sugar that produce the characteristic gel in jam. Different fruits vary in their amounts of pectin and acid. Cooking apples, black currants and damsons, for instance have a high ratio whereas strawberries have little. The acid helps to give the bright colour to jam and also prevents crystallization of the sugar. The ratio of these three substances determines the consistency of the jam. This ideally should be spreadable rather than stiff or glutinous.
My home made jams that keep well have up to 5% of the weight added from natural sugars found in the fruit. A further 60% of the finished weight of jam comes from the addition of granulated sugar. If the total percentage is less than 60% the jam may ferment and if the percentage is much more than 65% there is a danger that the jam will crystallise in storage. For most fruits, 2.25kg (5lb) of jam should be obtained from every 1.4kg (3lb) of sugar used.
Granulated cane or beet sugar is best for jam. Cane seems to give a better colour and flavour than beet. I avoid jam sugar (with added pectin) as it interferes with the flavour of the jam. The measured amount of sugar contributes to the flavour of the jam- not too sweet and not too fruity.
Alternatives to sugar such as honey upset the fruit favour of the jam. Glucose and glycerine do not
taste the same as cane sugar. Saccharine, a sweetening agent does not form a gel with the acid and fruit so does not preserve the jam.
The jam-season beckons. It is time for me to stock up with cane sugar to ensure the very best jam for the year ahead.
(1.) Food Standards Agency. The Jam and Similar Products Regulations 2003. Guidance Notes : http://www.food.gov.uk/multimedia/pdfs/jamregguid_rev.pdf