A jam making question.....

kippers

I've made quite a bit of jam this year and it has been lovely. However, i don't seem to get as many jars out of it as the recipes say. This doesn't really matter as its lovely, but i'm just curious as to why this happens.

Today i made plum jam as per Delia. She said it makes approx 5 jars, but i only just got 3. I used 2 lb plums and 1 1/2lbs of sugar. When it got to the point of boiling vigorously i boiled firstly for 10 mins and then a further 5 mins until it reached the setting point, so i don't think i did anything wrong.

Does this happen to anyone else and does anyone know why this happens?

shimmigirl

different size jars ??

not a jam expert myself - last time I made jam was 16 years ago at school!

kippers

No, the jars are the same size as delia recommended, but thanks for the reply.

Anyone else?

soappie

Maybe it's to do with the amount of flesh on the plums? If they have large stone and not as much flesh, there will be less 'pulp'.

The ripeness (or otherwise) of the plums may also have an effect - more/less juice from them etc.

chocolatechipcookies

Maybe it just happens. We made strawberry jam this year, with my mother in law at her house. We made it the same way she did, but ours was a lot runnier than hers.

pie-eater

I did plum jam yesterday with 2lb of plums and 1 1/2lb sugar and only got 3 jars too. So I must be going the same as you.:rotfl:

kippers

Thanks for replies.

Pie-eater, i'm glad yours worked the same and it's not just me.

thriftlady_2

I think it's to do with water content. All jam quantities can only be approximate because of the varying water content of the fruit. I expect it is affected by the weather, although my local farmshop reckons all the rain has made their plums extra juicy this year