A long-time canner and blog reader, Ramona, wrote in the other day with a good question about why jams tend to separate – meaning the fruit goes to the top of the jam rather than being evenly distributed through the jell.
Here’s her question:
I noticed on the mixed berry and rhubarb jam recipe you suggested letting the jam set before putting into jars and the water bath canner. You said this will help keep the fruit mixed. Does this help with other jam recipes? I have done canning for years, I am 76 years old and started canning with my Grandmother when I was a child. I have had several different jams to separate after the canning process. Would it help to let it set a few minutes before putting into jars? Pepper jelly especially separates.
Here’s something to consider …
While it may not completely solve the problem of the fruit going to the top of the jam, allowing the cooked product to sit a bit and then stirring it will help keep the fruit suspended in the jell. There are other factors that are in the mix such as unripe fruit, watery fruit, and many others and sometimes the floating fruit just cannot be eliminated. In that case, I stir the jam before serving.
Hope this helps.