I have a new early morning snack this week - toast and jam, but after putting the (fridge temp) jam on the toast, I put the whole plate of toast and jam in the microwave for 20 seconds to warm the jam. It's delicious, but some of the jams in my fridge are just way too sweet for me this way. That got me thinking - hundreds of years ago, jams were eaten at room temperature. But now they are eaten cold from the fridge as often as not. I wonder if the sugar level has been increased as a result.
Has anyone compared modern and very old jam recipes to see if this is a real trend? Or the sugar levels in supermarket jam compared to jam recipes in older books?