Cold fermentation of milk kefir is a great way to stay on top of your fermentation process. During the warm summer months, it can be very difficult to successfully ferment milk kefir. Often, the grains ferment the milk too fast. The kefir separates much quicker than usual leaving you with a watery, sour tasting kefir. We get many enquiries during the summer on the best way to deal with this problem. Our recommendation is the cold fermentation of milk kefir method.
If you have ever tasted mass produced kefir, you will notice it often tastes much milder than homemade kefir. This is because on a larger commercial scale kefir is always cold fermented. It gives more control over the process and gives kefir a longer shelf life. It also produces a much creamier, milder tasting kefir that is much more suited to the general populations palate.
1) If you have just received your grains from us, please activate them at room temperature and allow at least 2 weeks of normal fermentation before trying any cold fermentation of milk kefir. You need to ensure the grains are fully active and have recovered from shipping. Otherwise, it is likely the grains will produce poor quality kefir using this method.
2) The ideal temperature of your fridge needs to be 5 degrees. Colder temperatures than this will slow down the process and even totally halt it. Most people run their fridges below 5 degrees, This is a sacrifice you will need to make to ensure this method works well for you.
3) Milk kefir grains will grow much slower using this method. Occasionally they can go into hibernation. If you do not see any changes to the milk after 7 days, revive them by leaving them at room temperature for 24-48 hours.
The ideal ratio is 1 tablespoon (15g) of milk kefir grains per 250ml of milk. This ratio however is not set in stone. Generally, the more grains/less milk ratio will reduce the overall fermentation time. However for the best consistency and taste, we find this ratio works best.
It can take anything from 2-7 days to cold ferment milk kefir. It is dependant on the overall temperature of the fridge and ratio of grains to milk. Stir the mixture well each day and check for it to have thickened. You are looking for the consistency of a drinking yoghurt.
Milk kefir can still separate in the fridge. However it happens much more slowly and is generally easier to manage. If your kefir separates too quickly, increase the amount of milk used or reduce the amount of grains.
During the warmer summer months, this method gives you greater control over your kefir production. We highly recommend you try it! Cold fermenation of milk kefir is a really simple way to strop over fermentation and mellow out the taste of your kefir.