After last year’s enjoyable experience making shrubs (a shelf-stable way to preserve fruit with vinegar and sugar, for mixing into soda water, cocktails, salad dressings, and so on), I’ve spent a few more weekends trying new citrus, new vinegars, and different ratios, as well as using oleo saccharums (citrus oils extracted from the peel with sugar: I posted some photos of the process yesterday).
Bergamot / Cider Vinegar Shrub
Since much of the unique flavor of bergamot is in the zest, an oleo saccharum is key. I combined the peel of four bergamots with 2/3 cups of white sugar (let sit and periodically kneaded for about 10 hours, see photos)-- by the end of that time I could smell it even through the bag. I added that to the juice of 17 bergamots (about 2 cups), another 1 1/3 cups white sugar, and, by trial and error, 3/4 cups of my favorite cider vinegar (Bragg).
The vinegar flavor was a little overpowering, initially, but it’s supposed to mellow over time… and indeed, after sitting for a week it’s become one of my favorite shrubs– one spoonful livens up a glass of sparkling water.
Makrut Lime Shrub
I’d been brought a gift of fresh Makrut limes (which I’d never seen before), just on the edge of turning brown, and knew immediately I wanted to preserve their flavor with a shrub. The peel has the same distinctive scent as Makrut lime leaves, a dry, spicy, and floral citrus.
Since they’re so knobby, they were a huge pain to peel– normal peelers or zesters were useless, so I used a small knife and painstakingly trimmed off rind and then removed pith… ending up with the peel of 15 Makrut limes packed in 1/2 cup sugar to make an oleo saccharum, plus the juice of the limes (only half a cup, quite dry), and almost 1/2 cup of a very mild neutral rice vinegar. This gave me a dry, perfume-like shrub that’s great to splash into water or champagne.
Calamansi Lemongrass Shrub 
I don’t have the exact proportions written down, but this excellent shrub (probably my favorite basic citrus shrub) combined tiny calamansi (which I just sliced in half and packed in sugar, extracting both oleo saccharum and juice), additional lime juice, half a stalk of finely-sliced lemongrass, sugar, and champagne vinegar.
Meyer Lemon Peppercorn Shrub
The peel of 9 meyer lemons in ⅔ cup sugar, the juice of 18 (about 2 cups), another 1 ⅓ cups sugar, mint leaves, black peppercorns, and a mix of cider and white vinegars. Easy.
I’m looking forward to exploring further this summer once non-citrus fruits are in season…