S.c.o.b.y. = Symbiotic Culture Of Bacteria and Yeast!

SCOBY is the commonly used acronym for "symbiotic culture of bacteria and yeast", and is formed after the completion of a unique fermentation process of lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeast to form several sour foods and beverages such as kombucha and kimchi.Beer and wine also undergo fermentation with yeast, but the lactic acid bacteria and acetic acid bacteria components unique to SCOBY are usually viewed as a source of spoilage rather than a desired addition.Both LAB and AAB enter on the surface of barley and malt in beer fermentation and grapes in wine fermentation; LAB lower the pH of the beer while AAB take the ethanol produced from the yeast and oxidize it further into vinegar, resulting in a sour taste and smell.AAB are also responsible for the formation of the cellulose SCOBY.

Kombucha can be made at home with just a handful of ingredients. In this tutorial, we'll show you exactly what to do.

• 2 organic green teabags (or 2 tsp loose leaf)
• 2 organic black teabags bags (or 2 tsp loose leaf)
• 100-200g granulated sugar , to taste

1 medium scoby , plus 100-200ml starter liquid

For essential information on brewing safely, our top recipe tips and fun flavours to try, read our guide on how to make kombucha. Pour 1.8 litres boiled water into a saucepan, add the teabags and sugar (depending on how sweet you like it or the bitterness of your tea), stir to dissolve the sugar and leave for 6-10 mins to infuse.

Remove and discard the teabags without squeezing them. Leave the tea to cool completely before pouring into a large 2.5- to 3-litre glass jar. Add the scobyand its starter liquid, leaving a minimum of 5cm space at the top of the jar.

Cover the jar with a thin tea towel or muslin cloth so the scoby can 'breathe'. Secure with an elastic band and label the jar with the date and its contents.

Leave to ferment for one to two weeks at room temperature and away from radiators, the oven or direct sunlight. Do not put the jar in a cupboard, as air circulation is important.

After the first week, taste the kombucha daily – the longer you leave it, the more acidic the flavour will become. When ready, pour the kombucha into bottles, making sure to reserve the scoby and 100-200ml of starter fluid for the next batch.

The kombucha is ready to drink immediately, or you can start a ‘secondary fermentation’ by adding flavours such as fruit, herbs and spices to the drawn-off liquid and leaving it bottled for a few more days before drinking. Will keep in the fridge for up to three months.

Lemon & ginger kombucha 

Add the zest and juice of 1 lemonand 1-2 tsp grated ginger to 750ml kombucha and mix well. Pour into a flip-top bottle and seal. Leave at room temperature for two to four days, tasting daily, until it has reached the desired level of carbonation and flavour. Strain and chill to serve.

Berry kombucha 

Add a handful of chopped strawberries, blueberries or bashed raspberries to 750ml kombucha and mix well. Pour into a flip-top bottle and seal. Leave at room temperature for two to four days, tasting daily, until it has reached the desired level of carbonation and flavour. Strain and chill to serve.