This is a culture that contains small colonies of organisms (bacteria and yeasts) that grow and multiply in the medium used to feed them – milk or sugar water. They metabolize the sugars and fats and produce many beneficial micro-organisms. The yeasts in kefir kill harmful yeasts such as Candida albicans. Milk kefir produces the widest variety of beneficial organisms which in turn digest most of the lactose. One particular strain found in milk kefir is Lactobacillus rhamnosus which is of particular benefit in people on the ASD spectrum or who have IBS. Water kefir is popular with many people who stay away from dairy for one reason or another but does not contain the same numbers or variety of organisms as the milk variety.
By far the easiest to make and the most beneficial cultured food is milk kefir. Simply add kefir grains to room temperature milk, cover with a cloth and leave to ferment for 12 to 24 hours. The kefir is then strained through a plastic sieve and the grains either stored in fresh milk (to cover the grains) in the fridge until next time, or placed directly into more fresh milk.
A litre is a good quantity to make at a time but this may be more or less depending on the demand in your home. It is a good idea to culture your grains at least twice a week to keep them really healthy.
This produces a thin, drinking yoghurt style of cultured milk. It is excellent in smoothies, great for baking whenever sour milk or buttermilk, etc is asked for and may be used to soak flour to neutralize the phytates, etc.
If going on holidays, place your grains in fresh milk and place them in the
refrigerator while you are away. If the milk is very sour when you return, strain the grains and run them under clear water to rinse them before placing in fresh milk. If you are away for a very long time, the grains may be made dormant by placing them in clear water for up to a few months.