Sweet, sour, booze.

This little triptych of ingredients form the basis for a wealth of cocktails and mixed drinks that have been adored, pored over and modified since such a time that these recipes were recorded. We know the ones: sidecar, daiquiri, margarita; and we know the genres: swizzles, fixes, rickeys. All have been ripped in two and rebuilt with cut bases of spirits, flavoured syrups, botanical enhancements, fire and smoke, alchemy and voodoo. One thing that remains largely untouched however, is one of those three key elements: the sour. Lemon and lime (occasionally grapefruit) sit unchallenged at the heart of all.

In recent times bartenders have talked to chefs and equated themselves with verjus, the pungent sour grape juice used in many a demi-glace. But what if you wanted to delve a little more deep into getting as creative with your sours as you can with this sweet-infused syrups. Enter kombucha. Something we’ve been growing, harvesting and using as a sour base for the past two years.

It’s hard to declare this a niche product anymore - bottled, flavoured kombucha adorn every Whole Foods spin-off from here to Dumfries. However, for best results we reckon it’s best to make your own. Here’s for why:

• Bottled kombucha is a lot more expensive than lemon or lime (won’t anyone think of the GP!) making your own will cost you peanuts, just a little time and love :)

• Kombucha is a live culture, this means if you’ve done it right it will be unstable and change a lot over a matter of days. Whilst there are loads of adequate products on the shelf a lot is lost in the bottling process for mass-consumption. This is an evolving, living, fermented tea so, to get the most punch out of your booch you need to make your own and monitor it carefully!

• You can add whatever flavour you want and get a sour juice to play with! Our current iteration contains seaweed, bonito fish flakes, yuzu and miso. The result is a crisp, saline, acidic treat.

And here’s for how:

• Get a SCOBY; you can find these online or you can come and get off of us :-) And a 3L kilner jar. A bit like a goldfish, your SCOBY ( a culture of yeast and bacteria that looks like something out Aliens) will grow to fit it’s surrounds and then start making extra SCOBYs you can rip off and give to your friends!

• Mix up 2 litres of Oolong tea (the SCOBY likes an Oolong) with 300g caster sugar (this is important - complex sugars are not preferable as your SCOBY will struggle to break them down). Oh, and use proper diluted water, not tap water; limescale and chlorine are no good here.

• Place your SCOBY in it’s (sterilised!) jar and add the tea. DO NOT SEAL THE JAR! It needs to breathe. Just place some double layer muslin cloth over the top and rubber band to hold it. After two weeks drain off the tea, clean out the jar and add a fresh batch. You can leave a little of the tea in the base of the jar. If handling the SCOBY be sure to wash your hands in something like Cider vinegar to sterilise them.

• With your drained kombucha tea you should be tasting something pretty pungent and sour. If it doesn’t knock you back a bit it probably hasn’t been fermenting for long enough so put it back for a few days more. Once happy, this is the stuff you can start adding flavours too. Experiment with batching it in 500 ml brass lidded kilner jars. For each jar add a tablespoon or 2 of fresh juice and some other bits and pieces: cut fruit, ginger, honey, herbs, insects, seaweed etc. Seal for three days and then strain through a double sheet of muslin. Viola. If you want something fizzy, add more sugar at the start.

• The key thing is that even the drained tea will contain trace element of your SCOBY that will continue fermenting and growing in the second batch, so the juice should keep evolving toward sour; but, it’s definitely good for up to a week. Don’t seal your eventual juice as this could turn it fizzy too (unless that’s what you want).

For reference our current Ponzu Kombucha goes like this:

In a sterile 500 ml brass lidded kilner jar, add:

• 6 g kombu seaweed

• 1 tbsp yuzu juice

• 1 tbsp white miso paste

• 1 tbsp bonito flakes

Pour over raw kombucha tea up to the line; seal and date. Strain each lidded jar after 3 days through double muslin cloth.