Kombucha SCOBY mats

(S)ymbiotic (C)olony (O)f (B)acteria and (Y)east,

Mat - a polysaccharide biofilm matrix formed by the colony.

Both scobys come from the same source, a Birch Sap Mother from Nordic Food Lab. They are just over three months old. They have started to outgrow their jars, and so I have been sending pieces to other people who can nurture them and start their own kombucha obsessions.

The third image shows how the structure formed, layer by layer, over the last three months - generally speaking, a new feeding produces a new mat on the surface of the liquid which eventually joins up with the layers below, sometimes compacting into a homogenous mass. The furthest right round disk in the top image was around 1.5” thick before I sliced it horizontally.

These kombuchas have been fed on Pu’er tea, sucrose and honey. Sadly the ethereal, barely-there aroma of birch sap has vanished into the proverbial ether, but while the flavour exhibits nothing of it’s origins, its complexity is ever-increasing. I am using them as bases for all the other kombuchas I’m looking after, including bottles of strawberry, elderflower, gooseberry, lingonberry and cherry.

The english fruit season has become bountiful after a fortnight of sun and strawberries and cherries have benefited hugely - deeply coloured and with intense sweetness. They smell and taste exactly as they should.

This fruit came from Perry Court Farm, who have a stall at Herne Hill Market. Since my interests are directed towards drinks at the moment, I wanted to take all the juice out of the fruit, without using a juicer. I set water bath set to 41°C, one degree below the temperature at which vegetables are considered ‘cooked’ as opposed to raw. The temperature (more or less equal to a hot bath) is sufficient to soften the cell walls and draw the juice out of the fruit. The fruit stays relatively intact, so the juice that results is not as cloudy as it would be if it were cooked any hotter. Cooking in a vacuum-sealed bag means keeping hold of aromas that would be lost in an open pan.

The gooseberries are a little bit more tired looking, perhaps I am a week late for their sweet spot. I added powdered sugar (caster sugar would be slow to melt at low temperature), honey infused with pine shoots, and a branch of dried douglas fir and its needles.

After two hours I squeezed the fruit inside the bags and then heated them for another two hours. The cherry juice is destined for kombucha, with some birch sap scoby and mother, demerara sugar and gunpowder green tea. I will also add the crushed cherry stones - the benzaldehyde in the kernels will add an almond taste. The strawberry will probably also be turned into kombucha, and the gooseberries will become a fizzy pop, given life by adding some of my turmeric root and ginger ‘bug’.