Marmalade and mould

I am about to make some orange marmalade again but the last time I made some, after a while the top of the marmalade on each jargot a dark mould on top, The rest was still ok after skimming it off the top. BUT how do I stop this happening!

make sure you boil it well and store in an area not subject to extreme heat. Oh and also make sure enough sugar has been used.
other than that maybe make smaller batches and or freeze it, either as pulp or already made.
Any homemade jams seem to go mouldy in my pantry but have found another cupboard in a different area of the kitchen that is fine for storing jams and preserves in.

Use jars that seal, old jam jars are the best.I also use a sugar thermometer, I never test on a saucer now.

What temperature do you go to pickles!

Unless you really want jars, if you have freezer space, just put the marmalade into ice-cream containers and scoop out enough for one jar at a time.Because of the high sugar content, the marmalade/jam does not freeze, but remains gloopy and easily scooped out.

104 deg. C,220 deg. F
easy as.

Use a preserving pan, the wide surface allows for a good fast boiling, without a boil over. You do get to know when it is ready by that way the jam/ marmalade is behaving. If you don't have a preserving pan, ask your friends, if anyone has one they are not using.

I would give one of mine to a friend, if I thought they were genuinely going to preserve. I have gathered up lots, rather than see them get dumped.

Pour melted culinary wax in on top of the jars when they are full - it stops mould spores getting in.
It can be washed and reused.

Use jars with pop top lids.they are great and can be reused over and over!

Thanks pickles. I usually boil till it begins to bubble on the surface and begin to rise up in the pot. At that point it is usually at the setting stage. I still test though and keep stirring to prevent boiling while my test is cooling.

when learning a process I usually undertake an intellectual lesson first so that I know what to do. I have learnt that over ripe fruit will cause jams and marmalade to go mouldy:

http://www.howtodothings.com/uncategorized/a942-how-to-make-perfect-jammarmalade.html

There is a whole more stuff to know but this relates to your problem so you don't have to take my word for it.

luxy. use a mixture of citrus fruits, not just oranges. 2 lemons, 3 grapefruit and 3 oranges, that would make a good lot.
buzzy110.You may be boiling your marmalade too long. Mine usually sets after 5 minutes of adding the sugar. I don't like stirring it too much, rather rely on a good fast boil. You will be surprised how fast it will set. I get more jars of marmalade now, It dose not take long to boil away a jar or two.
I very thinly slice the firm under ripe fruit, soak in cold water over night. I remove the seeds, as I find them. A few get past me, all good for the "set".
Boil the fruit until it is very soft, remove from the heat, measure to calculate the sugar required. Heat the sugar in the oven, in a roasting dish.
Return the fruit to the pan, bring it back to boil, remove from the heat, add sugar and stir until the sugar is dissolved. Return to the heat source, bring to a good rolling boil. Take the temp. after about 4 minutes. There are times it will require more cooking, it is something you learn over the years. On saying that, I did have a lot of toffee once. Too much stirring, not boiling the marmalade hard enough, = a lot of toffee. Like everything we all have to learn. I have not always used a sugar thermometer, only the last 10 years. I wouldn't make marmalade or jam, without one now.