So to get food to ferment successfully, every time, means getting the good guys – whether it is bacteria, mold or yeast – to win the war. That is to say we let the bacteria, mold or yeast, that is not harmful to us, chow down on our food first.
In return they make the food better for our health and easy to digest, produce the flavours, enzymes and vitamins we are looking for and actually if we let them live they can keep the food alive and safe for a very long time.
This is surprisingly easy to do if we just follow some simple guidelines.
To give the forces of good a helping hand we need to tilt the table in their favour and we do this in any number of different ways:
Also refer Safety and Food Fermentation
- Using the right amount of salt (refer How Much Salt Should I use For My Fermentation) – the bad guys don’t like salt at all. Vegetable ferments start around the 1.5% salt mark and they go up to around full 5% strength. At 5% salt it pretty much gets rid of all the undesirables however the taste is a little salty for most people so we tend to use lower amounts.
- Decreasing the pH – A pH < 4.5 is totally hostile to the bad guys . This happens naturally once the lactobacillius bacteria start producing lactic acid – we can sometimes help the process along at the beginning by adding just a little vinegar or lemon juice!
- Increase the number of good guys – before the war has even begun we can load up the ferment with good bacteria. In other words load up the ferment with the good soldiers/bacteria you want by adding them before you start the ferment going. There are several ways to achieve this we can: Use 10% brine water from a previous successful ferment or even add probiotic powder from a probiotic pill.
- Lower the temperature – The bad dudes tend to prefer more tropical temperatures to the good guys. Keeping your crock somewhere around the 20 degree Celsius (68 degree Fahrenheit) plus or minus 5 degrees is ideal for most ferments. Which is not to say you can’t ferment if it is hotter or colder than that, you most certainly can, but if it’s hotter you may need to do shorter ferments or use a little more salt. Also refer The Best Fermentation Temperature.
- Cleanliness – it turns out is actually next to godliness when it comes to fermenting – normal washing up detergent and warm water is fine but it’s best to ensure your fermenting crock and utensils are nice and clean – not sterile.
- Use unchlorinated water – municipal water straight from the tap has chlorine and other chemicals to kill bacteria – either use filtered water or let the water stand for a while so the chlorine can evaporate
- Use sea salt – because table salt and pickling salt have weird additives that will interfere with your fermentation process
- For anaerobic ferments – like lacto fermented vegetables ensure that the water lock on your crock is filled with water at all times and avoid taking a peek.
- Submerge – all your vegetables under the brine as much as possible. The little bits of cabbage playing peek a boo at the surface can be a magnet for mold – but for short ferments of a few days don’t worry too much.
- Fill up the crock – with vegetables and brine and weights to around the 3/4 full point. If the crock is only half full there is a lot more oxygen accessible to the bad guys.