It’s that tang that hits you somewhere deep behind your molars. A fizz so delicate it’s hard to judge if it’s really there. It’s a compelling pungency that you can’t get enough of. It’s the work of microorganisms, and it’s delicious.
From kimchi to kombucha, from curd to camembert, living foods can be found in just about every cuisine in every corner of the globe. Humans encountered the chemistry, often haphazardly, and ever since, we’ve tried to wrangle and tame these microscopic lifeforms to do our bidding and create food with a mind of its own.
Here are three fermented foods to experiment with.
It’s believed that the first humans to come across yoghurt, or something like it, were herdsmen in Central Asia 6000 BC. They stored fresh milk in pouches that were fashioned from animal stomachs. The existing natural enzymes in these containers sparked a chemistry, resulting in a thicker substance with a sourness that the herdsmen liked, and so they kept making it.
There are two species of bacteria you can thank for yoghurt, namely Streptococcus thermophilus and Lactobacillus bulgaricus. These microscopic organisms feast on the sugars in milk, producing lactic acid. It’s this organic compound that causes milk proteins to curdle, and gives yoghurt the tang that we love.
To make the magic happen, you need to make sure that the microorganisms are present. And the easiest way of doing that, is using store-bought yoghurt as your starter. Here’s a simple recipe that will allow you to create your own batch of yoghurt overnight.
2 litres of full cream milk
½ cup of plain store-bought yoghurt (must contain active cultures)
- Pour the milk into a heavy saucepan that you have a lid for and heat up over medium heat. Keep stirring to avoid any burnt bits and get the milk to a temperature just below boiling.
- Remove the milk from the heat, and allow it to cool down until it’s warm to the touch. To stop a skin from forming on the top, stir occasionally.
- Scoop a cup of warm milk from your pot, and pour it into a separate bowl. Now add the store-bought yoghurt to the cup of milk and mix until the yoghurt is thinned.
- Now add the thinned yoghurt to the pot of warm milk and whisk until combined. The milk is now filled with microorganisms ready to feast. Put the lid on your pot, cover the pot with towels, and place the pot in a switched off oven. The idea is to keep the mixture warm while it sets.
- Now leave it and let nature run its course. You can check after 4 hours to see where it’s at, avoid stirring it when checking. If you want it thicker and more tart, leave it overnight.
- Once you’re happy, remove from the oven. If there is a bit of whey settled on the top, simply whisk it in. Now move the yoghurt from the pot to storage containers, and into the fridge where it can last for up to 2 weeks. And remember to keep a bit of this batch as the starter for your next batch.
Kimchi was born out of necessity. In Korea, where winter months make it just about impossible to grow fresh produce, people came up with an effective and tasty way to preserve vegetables using fermentation. It’s believed that kimchi has been eaten in Korea since the 7th century, but back then, it probably looked a lot different to the red, fiery version that’s most popular in the west today. It was closer to something like sauerkraut, as chilli peppers are believed to only have made their debut in Korea during the Japanese invasion in 1592.
Dozens, if not hundreds, of microorganisms are introduced through various ingredients. One of the star critters in kimchi is Lactobacillus plantarum that is carried by the cabbage. The microbial activity breaks down the carbohydrates into simple sugars. And these sugars, are broken down even further to produce other products, including lactic acid.
Many Korean families have gatherings to get all hands on deck and prepare their kimchi stocks for the months ahead. If you want to try a small batch that doesn’t require the skills or manpower of an entire family, try this recipe.
1kg of cabbage (regular or Chinese)
¼ cup salt
¼ cup julienned carrots
4 chopped green onions
¼ cup minced garlic
¼ cup fish sauce
1 t sugar
⅓ cup hot pepper flakes (gochugaru)
- Chop the cabbage into bite-sized chunks and place into a large mixing bowl. Add one cup of water, and the salt. Mix well and allow to stand while you prepare the paste.
- Add all the paste ingredients together in a separate bowl, and combine until a thick chunky paste is formed.
- Rinse the cabbage a few times with cold water, and drain.
- Mix the paste with the drained cabbage, ensuring that all the leaves are well coated.
- Transfer the kimchi into an airtight plastic container or clean glass jar. Push down to compact the kimchi, these microorganisms prefer low oxygen environments. Store for a couple of days at room temperature and enjoy as a side, or in a recipe.
The origins of this fermented tea are as murky as the brew itself. Some believe that ‘Immortality Tea’ mentioned during the Chinese Qin Dynasty is the kombucha of today. Some believe it is named after a Korean physician called Kombu who treated the Japanese emperor with the tea. The tea spread to Eastern Europe and Russia, where it has been consumed for centuries.
The base of kombucha is quite simply sweetened tea. The sorcery happens with the addition of the scoby (symbiotic community of bacteria and yeast) and starter tea. The scoby is a jelly-like disk that is placed in the liquid and inoculates the mixture with the microorganisms needed to start the fermentation process.
While brewing up a batch of kombucha may seem like a harmless weekend activity, it should be mentioned that things can go wrong. Bad batches of kombucha have caused serious health problems. So ensure that your hands, all equipment and storage jars are clean to avoid contamination. Also, do not use metallic utensils.
1 scoby (order online)
2 litres of filtered water
3 teabags (green, oolong or ceylon)
160g of white sugar
200ml of store-bought kombucha as starter
- Steep the teabags in 1 litre of boiling water for 15 minutes. Once the tea is at the desired strength, add the sugar and stir until dissolved. Add the rest of the water to bring down the temperature.
- Pour your kombucha starter into the vessel you’ll use for fermentation. Now add your sweetened tea to that container. Ensure that the liquid is at body temperature. If the water is too hot, it can kill the bacteria.
- Place your scoby into the container. If it has brown stringy bits, make sure those are facing down. Cover the opening of the container with a clean tea towel or coffee filter paper, and secure with an elastic band. It’s important that your culture doesn’t get contaminated by anything. Place your brew in a warm, dark place, like a kitchen cupboard.
- Depending on the temperature and surface area allowed for by the container, the fermentation process can take anything from 5 days to almost 3 weeks. After 4 days, check on your brew and see where it’s at. When there’s a frothy film forming over the top of the liquid around the scoby, it’s working. That layer is a new scoby forming. Move it aside gently and spoon out a bit of tea to taste. Taste every day until you’re happy with the balance of sweet and sour. The longer it ferments for, the sourer it becomes.
- Once you’ve got the taste you want, remove the scoby with clean hands and utensils and place on a clean dish. Strain the kombucha, leaving about 200ml behind in the bowl as the starter for your next batch. Decant into glass bottles with flip-top lids to avoid explosions. You can drink immediately, or store the bottled kombucha in the fridge or pantry for an extra month or so to enhance the fizz and get a dryer finish.
Terri De Sousa is a freelance conceptual creative and writer.
Animations by Marco De Sousa