About two weeks ago I wrote to Ball to ask about using their Real Fruit Pectin for microwave jam. I got a reply back saying that the product had not been tested for that.
Well, there is only one way to find out. I made some strawberry jam that was surprisingly good. This afternoon, I made peach jam with finely diced candied ginger in it.
I used the proportions in the drop down menu from Ball on its web site that is labeled "How much Pectin." You actually get complete fruit recipes. But I followed the microwave procedure from a recipe I got off the net for microwave peach jam.
In brief, prepare the fruit and mix with lemon juice (and whatever else you add--be it amaretto or ginger or whatever). Cook it on high for about four minutes, stir it and cook it until it comes to a full boil. About eight minutes total. Gradually stir in the pectin(so it doesn't clump) and bring back to a full boil for a minute. Add all the sugar at once and bring back to a full boil and boil hard for a minute. I think this took about an additional six minutes. I tested by letting it sheet off a spoon.
I used four cups of fruit, which Ball's recipe indicated was for six jars of jam. But I only got five. Duh. If you reduce the sugar by two cups total, you are going to get a cup less jam. So I think Ball needs to re-edit that page. Still, it is good to know it works.
I water bath sealed mine. But one could easily make a small batch with only a jar or two of jam and keep it in the fridge.