I love growing my own fruit and veggies, and even though I LOVE our house 'cos it's so close to the beach, the one downside is we only have a 500 m squared section. While I have quite a bit of room for my veggies (I don't think i'd ever say I had enough no matter how much space I had!), I have pretty much reached my limit on fruit trees. I managed to squeeze a few more in last winter but this winter I haven't even been near the garden centre - best to prevent any temptation!
Anyway, what i'm getting to is our friends bought a house with a HUGE backyard, full of established fruit trees - guava, tamarillo, apple, lemon, nectarine, and grapefruit. And they don't even particularly care for fruit! Foreign to me who eats fruit at breakfast, for morning snack, at lunch, for afternoon, snack, for pre-gym snack (you get the picture!). Luckily they are happy to share and i'm allowed to raid the garden whenever I like. You can find my guava jelly (jam) recipe here, and now for the marmalade.....
3 large or 4-5 small grapefruit
1. Remove green stems then roughly chop grapefruit, orange and lemon and put in a blender. Puree until you have your desired consistency - chunky or smooth. At this point you can freeze the mixture to defrost later to use in step 2 (handy if you're overloaded with fruit and over making jam!).
2. Place the puree in a pan and cover with water, bring to the boil and cook 20 minutes. Remove from heat and pour into a big bowl, then add back to the pan via a measuring jug to see how much liquid you have.
3. Add the same amount of sugar as liquid (make sure it's white - brown doesn't look so good, been there done that!) and bring to the boil again. Cook, stirring occasionally until setting point is reached - around 20-30 minutes. You'll start to see the mixture thickening on the back of the spoon if you rest it on the pot. Test by placing a small amount on a saucer that has been in the freezer - it will start to get a 'wavy' appearance when it's been left for a minute or two.
4. Pour into jars that have been sterilised in a low oven for 20 minutes. I boil the lids in water to make sure they're sterile too.