Are you struggling to maintain the perfect fermentation balance for your Kefir Grains during the cold winter months? Discover essential tips and techniques in this comprehensive guide to ensure your Kefir Grains flourish, despite the challenges posed by lower temperatures. Uncover the intricate relationship between yeast, bacteria, and temperature in Kefir fermentation, and learn the key dos and don’ts to avoid common pitfalls. Whether you’re a seasoned Kefir enthusiast or a curious beginner, this article will equip you with the knowledge to master Kefir fermentation all year round.
Problem:
<<< During the winter months the grains are rising to the top and the milk below is failing to culture.
Why is this happening?
Milk Kefir Grains are a unique combination of bacteria and yeasts that form a complex symbiotic culture. With over 50 different strains of yeast and bacteria, these cultures experience seasonal changes based on the environment in which they are placed. The very best milk kefir can only be cultivated once the balance between beneficial bacteria and yeast has been achieved.
During the dead of winter, our homes are much colder and hardly the ideal environment for culturing milk kefir. The best temperature range is between 75-80° F. Lower temperature ranges are where the bacteria has a harder time keeping up with the yeast. Higher temperature ranges are where the bacteria really thrive. In colder ferments, when the yeast produces CO2 the grains will rise to the top, which is usually perfectly fine but if the bacteria is not keeping up then the milk towards the bottom will have a hard time fermenting. This is illustrated in the diagram below.
So, what’s the problem?
During the colder winter months, the problem arises when the grains that have been pushed up by the excess CO2, creates a barrier. This barrier makes it harder for the grains to ferment the milk below. In a situation like this, it is important to know some Dos and Don’ts so that you can quickly remedy the problem.
| Do | Don’t | Details |
| Stir the grains and milk together in the beginning and just before you strain. | Do Not stir or shake the jar during the fermentation process. | Yeast thrives on air. Shaking during fermentation introduces more air. It can also speed up the separation of curds and whey by distributing the newly produced lactic acid through the jar. If the milk separates you can still keep it but it will be harder to strain out the grains. |
| If you need to take a break from the grains, place the jar in the fridge only after the milk has fermented. | Do Not leave grains sitting in fresh milk in the fridge. Do Not place grains in the fridge frequently. | When you place the fermented milk in the fridge with the grains it suspends the grain activity and keeps them more balanced. When you place them in fresh milk and then store them, the grains will either go dormant and the milk may go bad or they will ferment the milk at a slower rate and cause an imbalance of the yeast and bacteria. |
| Use the least amount of grains possible for the amount of milk you want to give them so that the milk cultures between 24 & 36 hrs. | Do Not let the grains do all the work of fermenting. The kefir produced by the grains should do most of the work. | The grains are the most potent part. Sometimes you need a tablespoon and sometimes all you need is a teaspoon. If the grains do all the work it will cause the milk to ferment unevenly. You want the kefir that the grains produce to do most of the fermenting. |
| Use Ultra Pasteurized Whole Cows Milk. It is the easiest and most forgiving. | Do Not listen to the criticism surrounding the use of Ultra Pasteurized Milk. This is bad information passed down from others. | When the milk is heated to such a high temperature it changes the structure of the milk. This helps the curds and whey bind and stay together more. It can also help the grains stay underneath the surface of the milk which will keep the beneficial yeast in check because it’s not exposed to any additional air. |
| Place the jar in a warm area (70-85° F or ideally 75-80° F) | The warmth will help the grains produce more kefiran (slime) which is a polysaccharide. The more kefiran the grains produce the creamier the kefir will be. | |
| Use a fermentation or warming mat | Do Not overheat your grains. | In the beginning, the grains sink to the bottom of the jar. The warmth radiating from the bottom jump-starts the grains, thickening the milk on the bottom. This will cause some of the grains to get stuck down there while others will rise to the top, creating a more even ferment culturing from the top down and bottom up. This is the mat we recommend. It doesn’t take up a lot of space and it has a dial on it so you can make sure it is not too warm and stays with the recommend range. https://amzn.to/47LXILD |
| Use a hard lid | Do Not use the metal lids that come with mason jars | In the beginning, the grains sink to the bottom of the jar. The warmth radiating from the bottom jump-starts the grains thickening the milk on the bottom. This will cause some of the grains to get stuck down there while others will rise to the top, creating a more even ferment culturing from the top down and bottom up. This is the mat we recommend. It doesn’t take up a lot of space and it has a dial on it so you can make sure it is not too warm and stays with the recommend range. https://amzn.to/3We6X40 |
| Use a shallow glass Tupperware bowl | Do Not use tall skinny jars | When the grains rise, they will be able to spread out more and not have a long way down to ferment all the milk. Glass also allows you to see what’s going on. |
| Reuse the same jar or dish | Do Not rinse it out | The curds that stick to the bottom and the kefir residue on the sides can help the next round ferment more evenly. Just make sure to wipe the rim and use a clean jar or dish every few rounds. |
While we understand that there will be a dissenting few who disagree with our recommendations, we are confident with the information we have given you. Having counseled thousands of people over my 13 years of milk kefir experience, I can say with confidence that if you follow these suggestions, you will keep your kefir on track throughout the colder season. Your success is my success.
*For additional resources to help you with your milk kefir see Adrienna’s YouTube channel @cleanfoodliving. Subscribe and give her a thumbs up if you like her video. Click on the link to watch a helpful video that can give you additional insights.