The best milk to use when making your own yoghurt is raw organic cows milk, which has not been pasteurised homogenised or processed in any other way. Most milk sold in supermarkets has been subjected to pasteurisation, a process which changes the structure of the milk and destroys much of the beneficial nutrition. Homogenisation is another process done to the milk which stops the milk from separating in the bottle, purely for cosmetic appeal. Homogenisation breaks down the fat globules changing the structure of milk even further.
If you do not have access to unprocessed raw organic milk then the next best is organic or biodynamic pasteurised only milk. Despite the fact that it has had some processing, the fermentation process will begin to restore the nutritional value.
Pour 2L of the milk into a saucepan and bring close to a simmer (stirring occasionally) as this kills off the bad bacteria which interfere with the fermentation process. Gentle heating is not nearly as destructive as commercial processes such as pasteurisation and homogenisation. However, do not boil the milk as this will change the structure and taste of the milk.
Once just simmering, take the pan off the heat. Cover the pan with a lid and place in the sink half filled with cold water to cool the milk down to 40-45C. If you do not have a thermometer wait until it is lukewarm (place on the inside of wrist, if the milk is slightly warm the temperature is just right).
Once the milk is lukewarm, add the starter culture to the milk and stir with a wooden spoon, try to avoid metal.
Pour the milk into 2x1L glass jars or a few smaller jars and close the lid tight. The yoghurt needs to be kept at a constant 40-45C. You can either wrap the glass jars in al-foil, keep them in an esky and a warm place or you can place them in the oven with only the pilot light on, which stays at a constant temp of around 45C (each oven may be different, you may need to turn the temperature on to just under 50C). Ferment the yoghurt for no less than 24 hours.
Once the yoghurt has fermented you can store it in the refrigerator. If you like your yoghurt thicker, or you wish to make cottage cheese and whey, line a colander or large glass jar with cheese cloth. Place the colander into a large glass bowl and pour the yoghurt on top of the cheese cloth and let it drip for a few hours to make thicker yoghurt or overnight in the fridge to make cottage cheese. Cover the top with a tea towel.
Whey is the liquid dripping from the yoghurt, a clear yellow-ish liquid which is very beneficial and filled with lots of good bacteria.
This can be kept in a glass jar in the fridge for several months. You can add this to smoothies, dilute freshly pressed juices down or use as a starter to ferment other foods. Both the yoghurt and cottage cheese can be used in baking, added to salads, soups or in desserts, or just as a snack with fruit and raw honey.
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