Rob’s Gardening Guide – Fermentation

Jar of orangey finely chopped vegatables with a white lid with a tube poking out of the top
Jar of orangey finely chopped vegatables with a white lid with a tube poking out of the top

Rob’s Gardening Guide – Fermentation

Rob Sleight in an electric wheelchair, a white man wearing a ventilator mask
By Rob Sleight

In my previous post about making use of some of the produce from your garden I talked about pickling. This time I would like to talk to you about the benefits of fermentation and how you can use that as a method of preserving your food. When you think of fermentation you might immediately think about its use in making things like beer and wine but it is actually a little bit more versatile than that. Whilst you can make alcohol with it, you can also use it to make tasty foods as well. Things like yoghurt and nutrient dense probiotic foods like kimchi and sauerkraut can be produced in this way. It might sound a little bit intimidating but once you get the principle down then it becomes a lot easier and you will get a bit more wiggle room for experimentation.

The benefits of fermented probiotic foods are many. There are a wide range of vitamins and minerals in the foods that we can eat but only a limited amount of them are accessible, fermentation can help your body to absorb a lot more of these nutrients. Fermented foods are also a brilliant way of improving your gut health. The probiotic bacteria or good bacteria can get right in there and help balance things out. There have also been studies showing that good gut health can improve mental well-being in some cases and also help your immune system. As we are getting well into the cold and flu season every little helps, especially given the current situation. I am not saying it can’t treat or even prevent this virus but if you are in a position to actually need to fight it then it couldn’t hurt for your body to be as fighting fit as it can be. So if you have to take anything away from this it is more nutrients, better well-being and also an immune system that should be a lot more on form. As a side note it also tastes pretty darn  good if I do say so myself.

So what is fermentation and how do I do it? You must be asking yourself. Well it is actually relatively simple. Fermentation is basically a form of controlled decay. It is a process where bacteria convert carbohydrates or sugars into alcohol (ethanol), gas (carbon dioxide) and an acid called lactic acid that pickles the stuff and gives it that tangy taste. Now you might be a bit concerned that there will be bacteria in your food but what you have to consider is that there are good beneficial bacteria for the human body and bad harmful bacteria in the human body. What we are wanting to do is make an environment for good bacteria to live that is also inhospitable to the bad bacteria. In this case the good bacteria likes an acidic anaerobic environment and anaerobic just means oxygen free. You can make an anaerobic environment by making sure that the food you are trying to ferment is submerged in a brine solution. In the case of things like kimchi or sauerkraut your main ingredient is cabbage and that has got a fair bit of water in it anyway so you can extract that by using salt and use that as a brine. For other things such as cauliflower you can make a brine solution of 2% which I will show you how to do in a bit. Then you can keep the thing in a warm dark environment and let the good bacteria do its job for a couple of days.

So by this point you must be getting a little bit fed up of theory and the itching for something a bit more practical. Well here it is, in this article I will live in showing you how to make kimchi. This is a spicy Korean fermented cabbage with garlic, scallions and other ingredients depending on your taste. You can vary the recipe depending on what it is you want but they all need to contain cabbage and Korean red chili flakes (gochugaru). It might be a bit of an effort to get hold of the chili flakes but you can either order the online or in an Asian market. Kimchi is not for everybody’s taste so I would recommend that if you can get to an Asian market then pick up a small packet of the stuff to see if it is something that you think you will actually like. Also, I think I should point out that it has a unique aroma and if you live in a shared accommodation that you might need to ask permission first.

Kimchi Recipe


  • 2 pounds napa cabbage (or bok choi/pak choi), cored and cut into 1 inch pieces or smaller if prefer. Sweetheart cabbage also works well.
  • ¼ cup sea salt (see notes)
  • 2 cups daikon radish, sliced thin or cut into matchstick strips (or use carrots)
  • 1 bunch scallions, trimmed and cut into 1-inch pieces or as preferred
  • 1 tablespoon fresh peeled ginger
  • 4 to 6 cloves garlic, whole
  • 1 shallot, quartered (optional)
  • 2 to 6 tablespoons Korean style red pepper flakes (gochugaru) See notes!
  • 2 tablespoons fish sauce or shrimp paste (or use vegan fish sauce, miso paste or soy sauce), adding more to taste but be careful as salty.
  • 2 teaspoons sugar or an alternative like honey, brown rice syrup
  • OPTIONAL: 1 tablespoon glutenous rice powder (see notes)


  1. Salt the cabbage (6-8 hours): Cut the cabbage and place it in a large bowl with the salt and toss with clean hands. Add enough cool water to cover the cabbage and stir until salt is dissolved. Keep the cabbage submerged with a plate over the bowl and let stand at room temperature 6-8 hours (giving a stir midway through if possible) or overnight.
  2. Make the paste just before draining cabbage: Place the ginger, garlic, shallot, red pepper flakes, fish sauce (or alternatives) and sugar in your food processor/blender). Add optional rice powder (see notes!) Process until well combined, pulsing, until it becomes a thick paste.
  3. Drain the cabbage saving the brine. Rinse the cabbage (not excessively, just a little quick rinse), drain, squeeze out any excess water, or blot with paper towels, and place it back in the bowl, adding the daikon radish (or carrot) and scallions.
  4. Massage: Spoon the paste over the cabbage. Using gloves (recommended), mix and massage the vegetables and the red pepper mixture together really well, until well coated.
  5. Pack the cabbage into a large 1892ml jar leaving 1-2 inches room at the top for juices to release. Add a little of the reserved brine to just cover the vegetables, pressing them down a bit so they are submerged. Use a fermentation weight placed over top to keep it submerged. Or a small freezer bag filled with water if you do not have weights. Basically anything that touches air may mould, but no worries if this happens (see notes) it is not ruined.
  6. Ferment (3-4 days): Cover loosely with a lid (allowing air to escape) and place the jar in a baking dish (or big bowl) to collect any juices that may escape. (The idea though, is to keep as much of the tasty juice in the jar, so don’t overfill it.) Leave this somewhere dark and cool at temperature between 10°c and 21°c for 3 days (ideally between 15°c and 18°c.) A pantry or lower cooler cabinet in the pantry or kitchen away from appliances works best.
  7. Evening of day 3: Check for fermentation action or bubbles. Tap the jar and see if tiny bubbles rise to the top. Check for overflow (which also indicates fermentation). If you see bubbles, it is ready to store in the refrigerator where it will continue to ferment and develop more flavour slowly. For a softer tangier kimchi, you can continue to ferment for 3 more days or longer. If no action, give it another day or two. If you don’t see bubbles when tapping the jar, it just may need a couple more days; especially in cooler climates. Be patient. See the troubleshooting section below.
  8. Refrigerate: After you see bubbles (usually 3-5 days) the kimchi is ready, but it won’t achieve its full flavour and complexity, until about 2 weeks (in the fridge) slowly fermenting. The longer you ferment, the more complex and tangy the taste. If you like a fizzy brine, tighten the lid, burping every week or so (releasing the gases). If you don’t want to think about it, give the lid one loose twist, so it’s on there, but gases can escape.
  9. Maintenance: This will keep for months on end in the fridge (as long as it is submerged in the brine) and will continue to ferment very slowly, getting more and more flavour. (See notes for adding more brine.)
  10. Serve: Serve it as side dish: scoop it out using a slotted spoon, place in a small bowl, drizzle with sesame oil, toasted sesame seeds and fresh scallions. Or Use it in Kimchi Fried Rice, Kimchi Burritos, Seoul Bowls, Kimchi Soup!


For milder kimchi, start with 1 or 2 tablespoons Korean chilli paste (you can always stir in more.)

If you like your kimchi, thick, and less watery, you can use sweet glutenous rice powder to thicken. This is not the same as rice flour! Cook 1 tablespoon glutenous rice powder with ½ cup water, in a small pot over medium heat, stirring constantly until it boils. Let cool, still whisking occasionally. Add to the chilli paste and blend or process then continue with recipe.

If you need or want to add more salt brine to the kimchi, to keep it submerged, mix water and salt at this ratio: 1 cup water and 1 1/4 teaspoon fine sea salt. Stir it together first, pour over the kimchi.

Avoid using table salt as it has iodine content which inhibits the good bacteria benefits in the fermentation process. Sea, Himalayan, pickling and kosher salts are preferred. 


  1. MOULD: If the cabbage surfaces too much and begins to produce mould around the jar, just wipe out the rim of the jar as best you can with a clean kitchen towel, and press the kimchi back down under the brine.
  2. NO BUBBLES: Check the temp of the kimchi using a kitchen thermometer if possible but not necessary as long as you have an idea of room temperature. Ideally, you want this between 10°c and 21°c, and perfect temperature between 15°c and 18°c. Too much heat may kill it off. Too much salt may kill it off also.

Good Luck.