Depends on the water level in the berries, and the humidity in the house...I'd say atleast 30 minutes..

Oh here's something for you...

Here is a link that might be useful: Pectin Free Blueberry Jam

This may be even easier..I'd store extras in the freezer...and make it in small containers because with small amounts of sugar it won't be a very long term keeper..

Here is a link that might be useful: Microwave Blueberry Jam

I also make blueberry jam without certo or sure jell because I don't like that much sugar in any of my jams. I've always added fresh lemon juice, just because it is so sweet and the lemon cuts that a bit, but I've never had problems with it thickening.

In fact, I made a blueberry syrup on purpose for pancakes and it jelled too!

Annie

thank you all. will do it next time...

I've stopped using pectins in all my jams/jellies whatevers, and I've cut way back on the sugar. I don't measure...but once in a while I will do the frozen plate test to see if enough water has evaporated. I also use opened jars up as fast as I can (within a 3-4 weeks) because of the low sugar, and I warn friends likewise when I give them away.

Jessica, as you know I've also given up using commercial pectin in an effort to cut down on the sugar. An added bonus is that I can often double a recipe, which is not a suggested proposition with commercial pectins.

You are right, the jams don't keep as long, but they still keep relatively well, at least long enough for me to eat them. Of course, I package everything in half pint jars, so they get used up.

Annie

I never even thought about Certo or Sure-Jell affecting the sugar levels! Guess I thought they were just Pectin.... do they have corn syrup in them?

My favorite BB Jam recipe is in the Ball Canning Book and is BB Lime Jam. The addition of the lime juice and zest make it so good.

How do you compensate for taking out the Certo/Sure-Jell from a recipe?

Grace

I hardly use pectin any more, either. I do use a thermometer, and it took me years to figure out the reason my jam was always hard was that I needed to adjust for altitude (water boils @ 206F here).

Grace, it takes way more sugar to make pectin jell. It takes longer to come to jell (gel?) point with no pectin, and the color may not be as bright. But at the fair my no-pectin apricot pineapple jam blew the prettier pectin jam out of the water once the judges tasted them.

I've made that BB Lime Jam...yum. I was thinking I'd use my no-pectin recipe and sub lime for lemon juice. The Ball Complete Book of Home Canning has a chart for Old Fashioned Jams.

I found about two dozen blueberries on our baby plants...can't wait 'til next year.

Grace, the pectin doesn't have sugar in it, it just requires a certain ratio of sugar to form a jell and if you cut down the sugar you could compromise the jell.

With no-pectin jams they are cooked to jell stage instead of relying on pectin to jell. I have cut the sugar down so far that instead of become a jelly or jam it becomes more like a fruit butter, LOL, but it always thickens if I cook it long enough.

It does take longer to make no-pectin spreads, though.

Annie

Thanks Annie and Katie for clarifying. I've only used pectin in my BB LIme Jam. My blackberry and fig preserves and the few other jams that I make are pectin free. I guess I just thought that some things had to have the additional pectin but I'm up for trying to just cook longer.... esp since I always have to make a trip to the store for the pectin!

Grace

You can shorten the cooking time (and freshen the flavor) by warming the sugar in the oven before adding it.

Some fruits do require additional pectin unless you're willing to settle for a looser texture. Since flavor tops consistency for me, if a jam or preserve is thinner but tastes wonderful, I'm fine with that.

The pectin and acid levels of different fruits will vary and it's extremely challenging to get both set and flavor with those fruits naturally deficient in pectin and acid. Pears are one example.

The problem with demanding a particular thickness is you keep cooking the jam but never really reach a jell point (due to low pectin). You're just evaporating out the water and eventually reach a point where the jam is like tar.

You can improve the setting qualities of jams by using 25% underripe fruit. The pectin is in the cell walls and as fruit ripens the cell walls collapse and the pectin level goes down. So underripe fruit has the highest natural pectin levels.

That's why it's very difficult to get a good set with dead-ripe fruit.

The other option is to make your own natural pectin from apples or citrus and add it to the recipe for a firmer set. Apple is the most neutral but orange would work wonderfully with blueberries or blackberries (and a little orange liqueur wouldn't hurt!)

Carol

Someone once posted a blueberry/mango jam. THAT was good!

I gave Lori316 a jar in a swap....

Jessica, I have blueberries and I have mangoes, so thanks for the reminder. Now to find some time...

Annie

I'm teaching a canning class tomorrow night, and I was wondering what kind of jam to make, (that's the first class, jams and preserves). Thanks for helping me decide. I'm going to make blueberry lime, it rocks!