How to rehydrate kefir – Happy Kombucha
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How to rehydrate kefir





You will need:

Dehydrated Water Kefir Grains 


  • Sugar: 4-6 Tablespoons 
  • White sugar or brown sugar; do not use honey, agave, etc. to rehydrated water kefir grains
  • Water (non-chlorinated) 
  • Well water or spring water is best due to higher mineral content . 
  • If using tap water, remove the chlorine prior to making water kefir by either boiling the water and allowing it to cool or by aerating  the water using a blender. 
  • One glass jar(at least 1 ltre) 
  • One towel or paper coffee filter to use as a covering for the jar 
  • Optional: A fine mesh strainer (plastic or stainless steel) for removing the kefir grains from the finished kefir

Activating Dehydrated Water Kefir Grains:

  Dissolve 4 to 6 tablespoons of sugar in 4 cups water (you will
likely need to heat the water so the sugar will dissolve). Be sure to allow the water to cool to room temperature before proceeding to the next step.

  Place the dehydrated kefir grains in the water and cover with a towel or coffee filter secured with a rubber band.Allow the grains to sit in the sugared water for up to 48 hours and then change the sugared water (by sieving out the grains and restarting with new sugared water).  Repeat this 3 times and the grains will become plump and the brew will start to smell a little vinegary and yeasty, when this happens the grains are ready to brew normally. The time it takes for the grains to fully rehydrate depends on the temperature they are kept at so do not worry if your grains hydrate slightly quicker or take slightly longer this is normal. Do not ever allow the mixture to sit for longer than 5 days.

  Once the grains are rehydrated, follow the normal kefir making instructions


  We do not generally recommend drinking the sugar water used to rehydrate the kefir grains.  Since the kefir grains spent their time rehydrating rather than consuming the sugar, the resulting solution will likely contain a large amount of sugar.  Also, the sugar water may taste unplesant as part of the rehydration process is the yeast and bacteria which comprise the kefir grains rebalancing.



  One pint or litre size glass jar

  A plastic or wood stirring utensil

  A breathable cover for the jar such as a tight-weave towel, paper towel, or paper coffee filter

  A rubber band to secure the cover to the jar

  Optional: A fine mesh strainer (plastic) for removing the kefir grains from the finished kefir

  One packet dehydrated Milk kefir grains

  Fresh Cow or Goat Milk. Do not use coconut, soy, nut milk, or any alternative varieties of milk for rehydrating. If using pasteurized milk, do not use milk that is close to the “use by” date. If using raw milk, we do not recommend using milk that is more than a few days old due to rising bacteria counts which can conflict with bacteria and yeast present in the Kefir Grains.


 When working with Kefir Grains, it is important not to introduce competing bacteria to the process. Be sure to wash and rinse your hands well prior to working with the milk or the Kefir Grains. Also be sure to thoroughly clean and rinse the container and all utensils that will come in contact with the Kefir Grains. Beware soap and food residue the dishwasher may have missed. When in doubt, give everything an extra rinse. The brewing vessel can be cleaned with regular soap and hot water (rinse several times very well) or with vinegar. Never use bleach on any item that will come in contact with the Kefir Grains.

Activating the Kefir Grains

  Place the dehydrated kefir grain in one cup of fresh milk and leave in a partially sealed container for 24-hours at room temperature.  

  Each day, strain the grain from the milk and add the kefir grains to fresh milk.  This process should occur even if the milk does not coagulate (kefir).  The strained milk can be discarded or used for cooking provided it looks and smells okay.

Choose a safe spot. An ideal culturing spot should be relatively warm but not excessively so. Temperatures between 70° and 80° are ideal. An ideal spot for making Kefir should be out of direct sunlight. Indirect light or darkness is neither favorable nor problematic. Be sure the spot has reasonably good airflow as access to oxygen benefits the fermentation process. In addition, be sure the Kefir is not fermenting near a garbage or compost bin, bread made with commercial yeast, or any other cultured foods such as kefir, yogurt, sourdough, sauerkraut, etc. Cross-contamination by stray yeasts and bacteria can be problematic for the Kefir Grains.


 Signs the Rehydration Process is Complete

  Within 4-7 days, the 24-hour milk batch will begin to smell sour but clean.  Eventually the milk will start to coagulate (kefir) within 24-hours (please note, if the area where your kefir grains are kept is cooler than 70 degrees, it may take 30-48 hours to see coagulation).

  The first few days may yield an overgrowth of yeast or a layer or froth or foam on the surface of the milk.  Within 5-7 days, the bacterial balance should stabilize and the kefir will begin to smell clean, sour and possibly of fresh yeast.  Under some circumstances, the kefir grains may take 2-4 weeks to start to making kefir.  Please be patient during this process.

  Once the milk is reliably turning to pleasant tasting and pleasant smelling kefir within 24-48 hours, your kefir grains are ready to generate regular batches of kefir.

Signs of Problems During Rehydration

While problems during rehydration are relatively uncommon, it is important to keep an eye out for these few signs that the process isn’t proceeding normally.

Time frame. If the milk is changed every 24 hours for more than 10 days and the milk is not turning to kefir within 24 hours, allow the milk and kefir grains to sit for an additional 24 hours (48 hours total). Ambient temperature in particular can affect how quickly the kefir forms. If the milk still fails to coagulate contact Customer Service for additional information to determine if the culture is inactive and if a replacement is needed.

Mold. While unusual, mold can and does occasionally develop and can generally be seen by the formation of white, green, orange, red, or black spots on the surface of the milk. If mold does develop, immediately toss the entire batch including the Kefir Grains. Do not try to salvage a moldy batch or a moldy Kefir Grains (even if there isn’t any mold directly on the Kefir Grains themselves). Doing so is dangerous to your health. Contact Customer Service for additional assistance.

Pests. Culturing Kefir is very attractive to ants and fruit flies which is why we recommend using a tight-weave cover and securing the cover with a tight rubber band to keep the invaders out. If you find worms (maggots) have infested your batch, this is a sign that fruit flies or house flies have invaded and laid their eggs. If this happens, immediately toss the entire batch including the Kefir Grains. Do not try to salvage an infested batch or an infested Kefir Grains. Doing so is dangerous to your health. Contact Customer Service for further assistance.

Next Steps

Once your Kefir Grains have finished rehydrating it is time to use it to make your first official batch of Kefir, Please use our normal milk kefir instructions for this


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