How to Make Kefir Taste Less Yeasty
Are you getting yeasty flavors in your milk kefir? In this post we take a look at what cause yeast tastes in kefir, and what to do to get rid of them.
One of the common complaints when its comes to the taste of kefir is that it can be yeasty in flavor. Kefir usually has a balanced flavor somewhere in between creamy, tart and just slightly yeasty. However these yeasty tones can increase to the point where they dominate the taste of your kefir and become unpleasant.
Before we get into what to do to stop this happening, let’s take a look at what is the root cause of overly yeasty tastes in milk kefir.
Why Kefir Can Taste Yeasty
The reason why kefir can taste yeasty lies in the balance between the microbes within the kefir culture. Kefir cultures (aka kefir grains or kefir SCOBY) contain a combination of yeast and bacteria species. The two groups of microbes assist and support each other and both need to be present for kefir to form. They work in tandem together and have a co-dependant relationship.
Imbalances in the Kefir Culture Between the Yeast and Bacteria
While the yeasts and bacteria need each other and work together to make kefir – imbalances can arise. This is because while the microbes are co-dependant, they are also in slight competition with each other.
Certain kefir making conditions, or the type of milk used, can cause the yeasts to dominate the kefir culture. If the yeasts gain the upper hand, then the kefir made by the culture will taste strongly of them.
What Can Cause a Rise in the Yeasts in the Kefir Culture
There are two main elements which cause encourage the yeasts in your kefir and cause them to proliferate and dominate the kefir grains. These are:
Temperature can play a big role in the microbial balance of your ferments. The acceptable range of temperature that you can brew kefir in is 65-85 degrees. The yeasts multiply rapidly and thrive at the warm end of this scale, while the bacteria prefer the lower temperatures.
So, if the temperatures are high – say between 70 and 85 – then you will most likely find that over time the yeasts are going to dominate the kefir culture. And this will result in those nastily strong yeasty flavors.
The kind of milk you use can also greatly influence the microbial makeup and balance of your kefir. The reason for this is that milk in its unadulterated state comes with its own set of microbes. These microbes are largely bacteria, and many of these are the same species as what live in the kefir culture. Pasteurized milk does not contain this contingent of bacteria.
Therefore using pasteurized milk for your kefir can be another cause of the kefir becoming overly yeasty. The yeasts are often naturally a little stronger than the bacteria, and if no fresh recruits of bacteria are introduced over time, and temperatures are warm, the yeast can easily gain the upper hand.
Maintain the Balance of Cultures for Trouble Free Fermenting
As you can see, the balance between the yeasts and the bacteria within the kefir culture is vitally important to getting good results from your fermentations. If you know about this relationship and how you can influence it, you can guarantee yourself hassle free kefir making. Having a balanced culture can eliminate all sorts of fermentation problems. This is true not just for kefir, but for other ferments such as kombucha and Jun tea as well. For some detailed info on the balance between yeasts and bacteria within the kombucha SCOBY, check out How to Lower Bacteria Populations in Kombucha and How to Increase Bacteria Populations in Kombucha.
How to Stop Kefir Tasting Yeasty
Now that you have an understanding of the behind the scenes goings on that cause yeasty flavors – let’s take at some specific ways you can brings the yeasts levels down.
Use Raw Milk
First up, if you are seriously struggling with yeast problems – try to source some raw milk for your kefir making. Raw milk literally soaks the kefir grains in bacterial richness each time you make kefir. This boosts the culture’s inherent bacterial population. Which means that you should not have to worry much about the yeasts getting the upper hand after switching to raw milk.
Unfortunately unpasteurized milk is sometimes hard to come by. If you cannot get hold of any, do not despair. You can maintain the balance of your kefir grains with the points listed below. It might take a little more effort, but it is by no means impossible.
Ferment Your Kefir Between 65 and 70 degrees
Controlling the temperature of your fermenting kefir is also a super effective step to maintaining the bacteria / yeast balance. If your kefir has been fermenting above 70 degrees, then bringing the temperature down into the 65 – 70 degree range will most likely give great results in reducing the yeasts.
How to Reduce the Fermentation Temperature of your Kefir
Look for a Cool Spot
When looking to lower the temperature of fermenting kefir, the first thing to do is to look for a cooler spot for your jars of fermenting kefir. Likely places might be rooms at the back of the house, and those which do not receive much sunshine. Also, surfaces such as stone tiles and granite tops often retain quite a lot of residual coolness which you can take advantage of. Remember that potential brewing places should be clean and free of rampant bug life.
Create an Artificial Cool Spot
- Ice and Cooler Box
Freeze some ice packs, or if you don’t have ice packs merely fill some plastic bottles with water and freeze those. Take a medium to large cooler box (having enough room is important as the ice must not touch the fermentation vessel) and place your fermenting kefir in it. Now place the frozen ice packs or water bottles around the sides, taking care not to let them touch the jar(s). Place the lid of the ice box on askew.
- Cooled Stone Slab
Bakers use cooled stone slabs to roll out rich pastry. This trick can work quite well for getting the temperature of your kombucha down. Get your hands on a stone slab. Once obtained, leave it in the fridge overnight. Let your kefir sit on top of this during the daytime, then cool the slab down over night again. This should allow for an even temperature, as usually the air temperature will drop a couple degrees at night, even in coastal areas.
Do a Fermentation Cycle in the Fridge
This is a method that some people use to quickly kill off any yeast overgrowth. Simply make up your kefir batch as usual, and place it it in the fridge to culture. It will probably take more than double the usual time to mature because of the super low temperatures.
You might find that your next cycle out of the fridge behaves slightly differently than usual. Hopefully part of this is a reduction in yeasty tastes! : )
48-72 Hour Batches
A long term practice for reducing and keeping the yeasts down is to ferment your kefir for longer. At first this will yield up slightly over mature kefir – but after awhile the grains should start to culture more slowly.
If the culture comes into balance and the yeasts are reduced, you will find that you can ferment your kefir for double or more time, and still get a kefir which is not overly soured.
The reason for this is that overly high levels of yeasts within your kefir grains are apt to cause premature souring and overly fast fermentation. Once the yeasts are reduced, the kefir can ferment slowly and steadily. Long and slower ferments tend to yield a much better quality of kefir which is creamy and has a better flavor profile which is not sharply tart or yeasty.
Soaking Your Grains in Yoghurt
Another way to rebalance your kefir grains is to soak them in live yoghurt! Yoghurt is a bacteria rich ferment, and has almost no yeast species present. Soaking your grains in the bacteria holding yoghurt will colonise them with a fresh bout of bacteria. This in turn will bring down the yeast numbers as they will be slightly outcompeted.
How to Do it:
All you need to do it get hold of some live unpasteurized yogurt and place your kefir grains into some of it. Use enough to cover. You can leave the grains in the yoghurt for up to 4 days.
When you remove the grains you can go on fermenting with them as you normally would. Hopefully sans yeasty overtones!
Washing Your Kefir Grains
Another method to quickly reduce the yeast levels in your kefir grains is to wash them. You can do this in between each batch of kefir making or simply as a once off way to physically remove a portion of the yeasts.
The way the kefir grains are structured, the yeasts are concentrated on the outsides of the kefir grains. The bacteria are found mostly in the center of the kefir grains. Washing with water removes some of the yeasts from the outer layers of the grains.
Do’s and Don’ts for washing kefir grains:
If you are planning on washing your kefir grains, whether once off or as a regular practice – there are two guidelines to follow.
- Always un non-chlorinated water. This is very important. The chlorine found in municipal water is directly antibacterial and will kill off some of the bacteria in your grains. These are the guys you are probably wanting to encourage – not kill off! Use purified water, filtered water or rainwater, groundwater etc.
- Do not wash your grains if you are having problems with slow fermentation or temperatures are very low. This is also an important point. If your kefir is struggling to mature, do not wash your grains. However, if you are battling with yeast tastes, then it is unlikely that you will be having problems with your kefir not maturing. This is just a word of warning.
The washing of kefir grains is actually quite a point of controversy in kefir circles – with a lot of conflicting instructions flying around. Wash your grains! Don’t wash your grains! Always rinse kefir grains! Never rinse kefir grains!
To the point where I think we should write a post on the topic. What do you guys think? : P
Best Practices for Keeping Out Yeasty Tastes
From the above list, the yoghurt method and the fridge method work well for quickly bringing down yeast populations in your kefir. Once you have gotten the yeast levels down, the aim of the game is to keep them that way. As mentioned above, the best ways to do this are to use raw milk, fermented at temperatures in the range of 65-70 degrees, and opt to do longer and slower ferments.
Of course, if for some reason the yeasts do start to rise again, you can try out the yoghurt, fridge or washing method to bring about a quick drop. And then make sure to carry on with the best practices once more.
Secondary Ferment for Saving a Batch of Yeasty Tasting Kefir
Doing a secondary ferment is a great trick for quickly remedying an already fermented batch of kefir which tastes too much of yeast.
How to do a Secondary Ferment:
- Select some glass jars with lids in which to do the second ferment. The best are the clamp down bottling jars, but if you do not have any of these, normal canning jars will work just fine. Pour the kefir into the jars.
- At this point it is also possible to add flavoring! You can flavor with any most kinds of fruit or fruit juice, different spices etc.
- Now seal up your jars tightly and leave them to stand and for fermentation to continue. The general time for a second ferment is between 24 and 48 hours. The ideal time is dependant on what the temperature is. The colder it is, the longer fermentation will take, the hotter the quicker. An 8 hour secondary ferment is suitable for very hot temperatures.
Once you stop the second ferment, you can transfer the kefir to the fridge and it should be ready to drink with a much milder flavor.
Second Fermenting Overly Mature Kefir
If the yeasty kefir that you have harvested is also overly mature for your tastes, it can still benefit from a second ferment. To really mild out the kefir – your can do the second fermentation in the fridge. Simply seal up your kefir as described above, and place it in the fridge for 2 days up to a week. You can open it and taste it along the way to see how it is progressing.
Second fermenting your kefir is a really great practice to get into. It produces the best kefir and gives a great opportunity for flavoring. It also ups the nutritional value of the kefir by significantly increasing the levels of B vitamins present, and the bioavailability of the calcium and magnesium in the kefir. The extended fermentation time produced by a secondary ferment also increases the probiotic value of the kefir.
For more detailed info on secondary fermenting your kefir, check out our post How to Second Ferment Kefir: The Ultimate Guide.
If you thought that yeasty overtones was part and parcel of kefir drinking – think again. With a little bit of know how and some simple steps, you can reduce the yeasts in your kefir. And by doing so, make kefir which is creamy, thick, mild and flavorful, without yeast flavors.
The key to all this lies in balancing the kefir grains and keeping the yeast populations in them down. Having balanced grains and lowered yeast levels not reduces yeast flavor notes – but improves the overall taste and quality of your kefir.
Keeping you kefir grains balanced microbially is the best way to ensure the health and success of your kefir ferments .