Jam Today preserves are pretty old fashioned when it comes to ingredients.
I do not use preservatives, thickeners, gelling agents, flavour enhancers or any of the other mystifying ingredients found in many commercial preserves today.
As an example my ingredients list for Damson Jam reads: Damsons & Sugar.
The methods are also essentially old fashioned. In my jam kitchen you will see knives, chopping boards, vegetable peelers and traditional preserving pans. (My most powerful machine is a slightly scary juice extractor designed for the domestic American market.) The preserves are finished by traditional open batch boiling and potted by hand.