This is exactly why I wanted vingar recipes. For the no sugar/etc folks. Rec: Blood Orange Vinegar
I wanted several, but specifically a blood orange recipe too, this is the only one I found. Haven't tried it yet though.
Blood Orange Vinegar
Yield: about 1 cup
What You Will Need
2 large blood oranges (or 1 blood orange and 1 Cara Cara orange)
about 1/3 cup good quality white wine vinegar
Instructions
Carefully cut the peel from the oranges, taking care not to cut away too much of the pulp. Cut the oranges in quarters, pull out any seeds, and put it all in the bowl of a small 4 cup food processor.
Whiz the oranges until they are completely pureed.
Press the orange puree through a mesh sieve, using the back of a large spoon to squeeze as much of the juice through as possible. Some pulp will also get through, and that's what you want. Be sure to skim off the pulp that sticks to the underside of the sieve, that's good stuff!
You will have approximately 1/2 cup or so of thick blood orange juice. Add about 1/3 cup of vinegar and stir well. Taste and add more vinegar if you like.
Pour the vinegar into a jar or bottle with a tight fitting lid and keep in the refrigerator. Give it a shake before using, and use within the month.
Notes
When I peeled my oranges I realized that I had accidentally gotten 1 blood orange and 1 Cara Cara orange, so I used them both. You can definitely blend varieties for this.
http://theviewfromgreatisland.com/2014/02/minimal-monday-blood-orange-vinegar.html