When Is Jam Set?

[gracewriter]

I've made jam a few times now for canning. Just actually canned my first batch a few minutes ago.

This is really confusing. Not worried about the canning part, but when do you know the jam has set VISUALLY while still inside the pot?

I've done all kinds of tests, drip, put in freezer, etc.

But it seems to me, there is a point when the bubbles get really big, and then the color of the jam gets really dark right after.

When it went dark on my blueberry, it turned into blueberry bubble gum. I put it back on the stove and added some apple juice and it came back to a good consistency.

I've so far made, blackberry, blueberry, strawberry, raspberry.

Problem is, I am making about a pint at a time and there are no recipes for such small amounts. So I'm winging it. Most have come out pretty good using 1:1 ratio by weight of sugar and fruit. No pectin, lemon, apple, etc. needed. They all have jelled using the guidelines I found. Some have over-jelled, but none under-jelled.

Can anyone help me out as to what to look for while it's still boiling in the pot? Do I look for really big bubbles? Do I wait until the really big bubbles get smaller and the color of the juice turns darker?

Thanks!

 

[taxlady]

I usually use two parts fruit to one part sugar (no added pectin), but sometimes I have to cook it for a lonnnnng time

I test like this: I put a plate in the fridge. I take it out and drip a small amount of the jam on it. I turn the plate sideways, so the jam drips down the vertical surface of the plate. Then I turn the plate 90 degrees, while keeping it vertical. If the jam doesn't drip again, it's ready. Put the plate back in the fridge. I made some fairly stiff jams on occasion before I realized that the plate had to be cold. o_0

 

[mcnerd]

If you have an instant-read thermometer, make sure your jam reaches 220°F before you remove it from the heat. That's the gelling temperature (at sea level) and is referenced only when you do NOT use commercial pectin. If using a recipe with pectin, follow its requirements of hard rolling boil for 1 minute after the sugar is added.

 

[gracewriter]

Thank you, but...

Thanks very much for getting back to me. I don't mean to be disrespectful, but I have tried all these methods.

My thermometer doesn't really work all that well. I'm 980 ft above seal level. Not quite 1000, but suspect I'm a few feet higher.

Anyway, I was reading someone's post where she was talking about what the boiling bubbles LOOK like when it has jelled.

It was hard for her to explain. Something like they get big and spurt? Not sure

Was also wondering about the color of the jam when it goes dark.

I appreciate all your help.

Thing is, when you are learning, it's a lot cheaper to just do one pint at a time.

My bubbles get really big, then get smaller, then the jam gets a darker shade. I only really ruined one batch of blackberries. But was able to use apple juice to thin it back out. Tastes pretty good.


I wish I had someone standing next to me who knew what they were doing. Tough trying to teach myself how to do this. But at least with the smaller batches, it's a bit more economical.

Also with the smaller (tiny) batches, seems it cooks up a lot quicker than the recipes for larger amounts.

I have another question about raspberries, so I'll start another thread.

Thanks a million!

 

[CharlieD]

I usually use one to one ratio and at the end I add some citric acid as a preservative. To answer your question, I use drip check. I put just a tiny drop on my thumb nail and turn it around if it doesn't drip it is done. Another tip I use the amount of jam should decrease approximately by half.

 

[mcnerd]

If you are not at sea level you can find your particular 'gel temperature' by bringing water to a rolling boil and measure the temperature and add 8° to it.

Not all fruit is equal with the amount of natural pectin in them. The whole reason for commercial pectin is to avoid the necessity to overcook some fruits in order to reach a gel state.

Making jams and jellies is still an "art" in understanding chemistry, so I would stick to tested and approved recipes and especially avoid making large batches which almost guarantees an inability to reach a gel state.

If all else fails buy Pomona Pectin.

 

[gracewriter]

Thanks!