I have been making marmalade the same way for years for a Christmas giveaway. I bought a microplane zester that produced very fine bits of rind. Over time I have been experimenting with the recipe— no extra water, fine bits of zest and less and less sugar. This has produced an intensely flavorful marmalade.
I have learned that you can make marmalade out of any citrus fruit. A few weeks ago, I was looking a bag of mandarin oranges and thought, “Why just make boring old navel orange marmalade?” The jam this idea produced was so good that it did not last very long.
Last week, Eilene—who is not overly fond of orange marmalade in her PB&Js—requested that I make something else. I made some strawberry jam, like my mother used to do. However, the recipe that I had adapted called for a different way of handling the sugar than I normally did.
For years, I have brought the fruit mixture to a boil and then added the sugar to the pot. Ina Garten started by melting the sugar and then adding the fruit. I made the mistake of cooking my sugar too long and I had accidentally begun to caramelize the sugar—the Maillard reaction had started to kick in and produce some complex flavor molecules. This produced an amazing strawberry jam. Small changes in technique can produce big changes in flavor.
I realized that when the sugar was in a lot of liquid, it was not able to get hot enough to caramelize effectively. The dry pot allowed the sugar to heat to a higher temperature. For this batch of jam, I decided to I would caramelize the sugar on purpose, to see where it would take me. It led me somewhere very nice.
Note: Mandarins are very small fruits. They have very thin, delicate peels that are hard to zest. They also produce much more zest than juice. You will only need half of the zest that these mandarins will produce. You can make orange infused sugar with the rest, if you do not want to waste the excess zest.
Karl’s Caramel Mandarin Micro Marmalade
1½ cups sugar
3 lb. mandarin oranges, juiced (about 2½ cups)
½ cup mandarin zest
Note: This recipe produced a bit more than two cups of jam.
1. Zest and juice the mandarins.
Tip: Once you zest the oranges, they will be very hard to juice with a rotary juicer. You will have to support the peel using your palm.
2. Put the fruit and zest into a non-reactive pot and bring the juice mixture just to a boil.
3. As soon as the juice mixture comes to a full boil, remove it from the heat and cover the pot.
4. Set the pot aside and let it sit for at least 12 hours.
Tip: You will have had some lost of the volume to evaporation from the heating and resting of the mixture.
Note: You may skip this step if you are in a hurry, but this heating and resting allows the bitter compounds in the rinds to break down into the complex flavor compounds that you associate with “real” orange and lemon flavors. This resting period is one of the secrets to my jam’s intense, but smooth taste. Twelve hours is a minimum, but I have let the mix meld for as much as two days, with a second heating after 24 hours.
5. In a medium pot, bring the fruit mixture to a simmer.
Tip: If you pour cold juice into the hot caramel it will splatter a lot and possible burn you.
6. Put the sugar in a second large pot and add ¼ cup of the fruit and zest mixture.
Tip: This liquid both helps the sugar get started melting and it also provides some mandarin zest that will be effected by the Maillard reaction and give the jam a pleasant slightly “burnt orange” flavor.
7. Heat the sugar mixture over a medium high heat for 15-20 minutes, until the caramel has reached the color you desire.
Tip: The longer you cook the sugar the darker brown and more flavorful it will become. Of course do not go all the way to black, because then it will have burned and that will not taste good.
8. Slowly pour the juice mixture into the caramel and stir to melt the sugar.
Tip: Be careful to scrape the bottom and sides of the pot. Any caramel stuck there could burn and ruin your marmalade.
9. Cook the jam until it starts to jell.
Tip: This can take anywhere from 30-45 minutes for mandarin oranges. How long it takes depends a lot on how close to a full boil you are cooking the mix. A low boil takes a bit longer, but a high boil must be constantly watched and stirred to prevent boil-over and scorching.
Note: Testing for jelling: 1) Take a teaspoon and scoop out about half a teaspoon of the jam. 2) Let it cool for two minutes and then pour it back into the pot. 3) If the mix pours in a single stream then it has not started to jell. 3) If the mix slides off of the spoon in a wide sheet it has started to jell.
10. Pour the marmalade into sterilized jars and seal the lids, not quite tight.
Tip: You want the lids tight enough that the water does not leak into the jar, but loose enough that the heated air can escape. This is about an eight of a turn short of completely tight. The easiest way to do this is to tighten the lid completely and then unscrew the lid an eight of a turn.
11. Put the jars in a hot water bath and boil for ten minutes.’
12. Remove the jars and seal the lid tightly.