This is my first attempt at what will hopefully be a series of "barrel aged" fruit preserves.
I started with standard jam jar sterilization, but I also had my bourbon barrel pieces to consider. The plan is to age each jar of marmalade with a small piece of barrel. To minimize contamination, the wood pieces were briefly soaked in the nearly boiling sterilization water. The excess water was drained off and they were also soaked in a small amount of 95% AVB Everclear. The wood pieces seemed almost dry by the time they were placed in the jars, but my hope is that any residual alcohol will only help flavorful compounds diffuse out of the wood.
As a second flavor booster, I also made some of the marmalade infused with a dark chocolate flavor. I did this simply by pan toasting a small amounts of cacao nibs and placing them in the bottom of three of the jars. Then it was time to simply make the marmalade. In this case it was three regular oranges and one blood orange, thinly sliced on a mandolin. This totaled 635g of orange which was simmered in water for 45-50 minutes, before roughly double it's mass in sugar was added. Once everything was combined the mixture was brought just to 105°C and then portioned as quickly as possible. Each jar was filled about half way before a piece of bourbon barrel was placed in the jar using sterilized tongs. All the jars were then topped up, sealed, and boiled together for 10 minutes. Overall this was the perfect amount for six 250ml jars, with only a small amount of primarily syrup leftover. The consistency is a bit on the thin side but I think this might be ideal for actually allowing the flavor compounds of the wood to diffuse. I plan to let the jars age for at least two months before trying one and seeing what effect there is.