Water Kefir FAQ: Preparation and Supplies

Water Kefir FAQ's 

 

Questions in this Section:

How do you make authentic water kefir?
Do I have to start using my fresh kefir grains right away?
What do you need to make water kefir?
What is the purpose of the lemon and the dried fruit?
What kinds of sugars can you use?
Does it have a sugar preference?
How do you stir in the sugar?
Does it matter what order you put the ingredients in?
Can you substitute an orange, lime or grapefruit for a lemon?
Should you squeeze the piece of lemon or put it in whole?
How much lemon and/or dried fruit should I be using?
Is it ok to use waxed/conventional or bottled lemons vs organic?
Can you substitute the previous batch kefir or vinegar for the lemon?
Should sulfates and other preservatives on dried fruits be avoided?
Do the ingredients have to be organic?
How do I de-chlorinate my water?
What kinds of dried fruit can you use and which are best?
Can you use fresh fruits, vegetables or grains (such as rice) in the ferment?
Can you make your own kefir grains or get kefir from just water?
Can you use artificial sweetener or vitamin-infused water with kefir?
Does it matter what water you use?
Do kefir grains have a water preference?
What about reverse-osmosis water?
What about well water?
What is the optimal water to sugar ratio?
Is metal a safe material to use?
What type of container can I ferment and store my kefir in?
Do utensils need to be sterilized for kefir similar to making yogurt?
How much or how little water (and grains) can be used?
How much or how little kefir can I make?
Do you always have to use the grains to make kefir?
Does the water have to be warmed before adding it to the grains?
How full can I fill my kefir jar?
What temperature does water kefir prefer?
Should I put a lid on kefir?
Does kefir need a breathable lid?
Can you use kefir liquid as a starter (instead of the grains)?
Can kefir be in direct sunlight?

How do you make authentic water kefir?

Water Kefir is very simple to make, and its fun to watch the process. It requires a few more ingredients than milk kefir (which just requires milk). People have been using kefir grains for thousands of years, before refrigeration, hand-sanitizers and antibacterial soap, measuring cups and filtered water - it is a wonderful simple, safe traditional method to preserve and convert sugar water to a delicious drink! Water Kefir can be made from almost all water (except reverse-osmosis or heavily chlorinated). All you need to add is some sugar, a couple pieces of dried fruit (sometimes) and a little lemon (sometimes). In short, the grains simply need to be placed in a jar of water with about a 3-10% sugar solution (1/4 cup sugar per quart water is about right - see below in this section for best kinds of sugar) at room temperature, filled about 60-75% to the top, toss in some dried fruit (see below in this section for best kinds), a quarter to half a lemon, stir it and cover it with a loose lid or cloth. In 24-48 hours (we usually do 48 hours, even in the summer)you will have a delicious kefir! Simply strain to retrieve the grains, put them back in the jar with the same combination and repeat! This can go on indefinitely as kefir grains often outlive their owners! With the strained kefir you can bottle it and let it 'ripen' out on the counter for another day or two, store it in the fridge, or drink it right then and there! Our guide goes into more detail step-by-step for this process.

Do I have to start using my fresh kefir grains right away?

Fresh kefir grains are active and trying to eat. They will most likely have exhausted the nutrients in the liquid they were shipped in, so its important to get them started as soon as possible. If that's not an option, place the package directly into the fridge, where it will keep for about a week or two (though this is not recommended, as they will degrade in strength and quality and may end up pickling themselves).

What do you need to make water kefir?

All you need is basically what the little kefir grain image is holding on the top of this page - a blend of white cane sugar, less refined sugar (like rapadura or molasses), some dried fruit, a lemon, and some water (and the grains of course!). You will want a small handful of raisins, or 2-3 apricots for each ferment, about 1 tablespoon sugar per 1 tablespoon grains for each ferment and about 1 cup of water for each tablespoon grains (for each ferment). Since most ferments are about 48 hours, a gallon jug will suffice for 1 week if you need to buy your water, and you will want to pick up about 3 lemons, at least 1 lb sugar and a big bag of dried fruit. You will also want some jars, paper towels and a strainer (plastic, wood or stainless steel) and bowl on hand.

What is the purpose of the lemon and the dried fruit?

The purpose of the lemon is to aid in lowering the ph of the medium so as to deter foreign contaminants. Lemon has a low ph (very acidic) and naturally hinders germs and weed bacteria and yeasts from getting an upperhand. This is more crucial when your grains are just starting out and need the additional help and support. The lemon peel also is high in calcium, an important nutrient for the grains. Once your grains are strong and growing and fermenting successfully and consistently, it is not necessary to use the lemon. In fact at this point you can even use about 1/8-1/4 cup of the kefir from the last batch as your 'acidic' ph lowering tool. Since in the past this was most likely done as a continual ferment (a ferment that you drink out of and then replace that amount with fresh water and sugar, never straining the grains out) this would have been the case that enough of the liquid was already low in ph to protect the ferment. The dried fruit serves as additional minerals and other micro nutrients that are either not supplied by the sugar or water, or are an additional source of minerals with the water and sugar. Again, this is something that needs to be tinkered with, as water varies location to location, and while one fruit high in calcium is good in one area, may be too much in another that already has water with high calcium. You will know what works best by whether the grains respond favorably (grow more rapidly and produce a more tart or bubbly kefir). Our grains with our water right now prefer turkish apricots the best. The fruit may not be necessary if you are able to get some good blackstrap molasses or rapadura sugar to replace some of your white sugar. But if you are using all white sugar, it is definitely recommended to include the dried fruit for the minerals that your grains will need.

What kinds of sugars can you use?

Palm (coconut), Sucanat, Rapadura, Muscavado, Demarara, Panela, Jaggery, Turbinado, brown sugar (both light and dark), molasses (both light and dark), maple syrup (pure maple), white sugar, sugar cane juice, whole cane sugar, raw sugar, powdered sugar, basic white sugar, swizzle sticks (sugar cane stalks), and Piloncillo (evaporated sugar cane juice in a cone-shape found in Mexican markets).

Does it have a sugar preference?

Water kefir grains are unique from batch to batch and season to season. We have found ours to prefer whole cane sugar (Rapadura) or Palm Sugar mixed with white sugar in the summer and a blend of white sugar and blackstrap molasses in winter. They can also readily adapt and be happy with brown sugar or Piloncillos. We've noticed this has also been the case for many others as well. While the other sugars mentioned haven't given as good of results for us, they may for your grains. It is always worth trying a variety, and when the grains start to under-perform, try switching things up. In our time watching water kefir behavoir, we've noticed it can 'get tired' of what it is in, needing a switch-up of sugars - we think this is likely due to the fact that no one food (or sugar) contains all of the vitamins and minerals, and the grains simply are needing to be exposed to variety to obtain what they need. Some sugars are more difficult for them to process and some process very rapidly - making raw cane sugar better in the summer when they are fermenting more rapidly, but too difficult sometimes in the winter (when molasses seems to supply the minerals that whole cane sugar does, but in an easier form). Again, this is what we've noticed so far with our grains, but water kefir grains are quite finicky and always changing - its best to test a wide variety of options for your grains, and being flexible to change when your grains tell you they need something new.

How do you stir in the sugar?

Simply add the sugar to the grains (doesn't matter, before or after you put the water in the jar), then stir for about a minute until the sugar is atleast somewhat dissolved and evenly distributed. It doesn't have to be perfect. You don't need to do any special process to dissolve the sugar into the water.

Does it matter what order you put the ingredients in?

There is no real necessary order, we only recommend leaving large fruit and the lemon wedge out until just before putting the lid on (they can get in the way of any stirring needed). Simply put your strained grains into your fermenting jar, add the sugar, and top off with water. Stir to dissolve the sugar for a minute and then drop in any dried fruits and lemon wedges that you wish to use. If you wish to add additional minerals such as baking soda, just put that in with the sugar so it gets stirred in evenly.

Can you substitute an orange, lime or grapefruit for a lemon?

You can try replacing the lemon with a wedge of orange, lime or grapefruit but it's best to test first on your extra grains and keep a separate batch going in the traditional recipe. If they respond favorably, or show no difference, then these can be a satisfactory (and tasty) replacement.

Should you squeeze the piece of lemon or put it in whole?

You shouldn't squeeze the lemon, it may actually lower the ph too much, without being gradual. Simply put a quart or a half of a lemon in, and when you have finished fermenting and bottling the kefir, you can squeeze the lemon into your kefir beverage if you desire.

How much lemon and/or dried fruit should I be using?

You will want a small handful of raisins, or 2-3 apricots for each ferment, using a quart of water as the base measurement here. Basically whatever can just cover the palm of your hand is a good indicator of quantity to put in. You can do a quarter of a lemon or up to a half of a lemon in each ferment. Some people re-use their dried fruit and lemon for another ferment, before finally tossing them and starting fresh.

Is it ok to use waxed/conventional or bottled lemons vs organic?

It is ok but not recommended. If you only have access or a budget for conventional lemons though, simply peel it - this gets rid of the bulk of wax and any other preservatives or pesticides that may be coating the lemon. Be sure to wash the lemon with hot water and scrub off any dirt etc if you are not peeling it (organic doesn't always mean clean or safe either).

Can you substitute the previous batch kefir or vinegar for the lemon?

Yes, the previous batch of kefir will act as a ph lowering aid, just as the lemon would have. Sometimes this can cause an increase in yeastiness and foam at the top because you are carrying over more bacteria and yeast (live and dead). The other thing you may be missing out on is the added nutrients from the lemon, such as the calcium in the rind. However there are most likely other beneficial nutrients in the 'starter' liquid too - the best of both worlds is to switch between the two. Water kefir has shown us time and again that it does actually get tired of one way, perks up from a change, and then is ready to return to something else. When your water kefir is showing a strong healthy growth rate and kefiring ability, it may even benefit from a break from either - there are many, many people who opt out on even putting the lemon or starter liquid in, and have no problems whatsoever.

Should sulfates and other preservatives on dried fruits be avoided?

Yes, it should be avoided, but it is not detrimental. Green/golden raisins tend to have more preservatives in them - so be aware when buying to check for that. In our observations it seems to only slightly impair the ferment - around 0-10% difference is noted when comparing a conventional raisin with an organic preservative free raisin. Sometimes we cannot tell the full range of effects (or no effects) that something may have, so we always suggest to try to stay away from sulfates and sulfites if possible - fresher and more natural is always better however you look at it.

Do the ingredients have to be organic?

No, they do not - the lemon can be peeled to avoid the conventional waxes and sprays on the rind, and the raisins can be conventional or organic (preferably preservative free either way). The grains respond to conventional and organic sugars only by quality and not necessarily by whether its organic or not. Sometimes organic products have less additives in them (like molasses), and the kefir grains do respond more favorably to that, but it is not absolutely crucial that your ingredients be organic.

How do I de-chlorinate my water?

You can let your tap water sit out in an open container for a minimum of 6 hours (chlorine will fully evaporate in an open container within 6 hours according to the city works department site) with most recommendations set a little longer at 12-24 hours (according to some aquarium and tropical fish experts). Chloramine is another form of chlorine that will not evaporate - if you're concerned about this you can find out from your local water department whether they treat your water with this. If you're worried about the cleanliness of your water or other contaminants besides chlorine, boiling kills off most types of organisms and is the most recommended purification technique in this case. Boil the water at full rolling boil for 1 full minute, then let it cool (if you are more than one mile above sea level boil 3 minutes longer).

What kinds of dried fruit can you use and which are best?

This is a tough question because part of the process of finding what works for your own water kefir is finding a compatible combination of fruits to go with the water and sugars you're using too. For example some parts of the country (or world) have hard water (highly mineralized) and some have soft water. If you are using all white sugar and soft water, your kefir will most likely prefer lots of fruits with dense minerals and nutrient value. On the other hand if you are using a mix of molasses with your white sugar, and mineral water - you may need no help at all from fruit except occasionally for taste, a nutrient boost if your grains get 'stuck in a rut' or variety. The best fruits do tend to be the ones we know as nutrionally dense - such as figs, dates, bananas, coconut, apricots, apples, raisins, mangos and sometimes dark cherries too. These fruits start out dense and dry to still be large pieces of fruit. If you dried a large slice of watermelon, you would be left with a flake of paper (unlike an apricot which remains pretty hefty for a dried fruit) - basically if fruits are extremely high in fiber or water, the kefir grains do not seem to respond as well. Because of this, berries, citrus fruits and melons make for poor nutrition for the kefir grains. It's always best to get dried fruits that have no added preservatives (like sulfates or sulfites) and no added oils or sugars. You may be suprised that a lot of dried fruits have added oil and sugar (and even sometimes salt) especially ones that come pre-packaged as snacks.

Can you use fresh fruits, vegetables or grains (such as rice) in the ferment?

Yes, we have actually found our kefir to take to carrots a bit at times. Root vegetables have a high sugar and mineral content (like ginger, which is a root) and kefir sometimes will benefit from a couple fresh slices of carrots or ginger. Brown rice also seems to be compatible with kefir grains, and we would imagine many other grains to be as well (in their whole form - not white rice for example). Try experimenting with your extra kefir grains and see what they like! We don't recommend nuts because of their high oil content. Vegetables like garlic and onion have irritating compounds for the grains as well, and most likely will not be beneficial.

Can you make your own kefir grains or get kefir from just water?

No, kefir grains must be obtained. Kefir grains reproduce, but one cannot create the grains or have them spontaneously occur in sugar-water. Honey and water can be left out to eventually produce mead (a type of beer) from wild yeasts and bacteria in the air; you can also use that mead mix as a bread leavener, however those bacteria and yeast do not form into the unique mass symbiotic matrix of kefir grains. Either way, kefir cannot be created and is not reproducable without obtaining real kefir grains to start with.

Can you use artificial sweetener or vitamin-infused water with kefir?

Artificial sweetener does not work with water kefir. This is because it contains no calories or nutrients. The kefir grains simply have nothing to eat and live off. Vitamin-infused water or water brands like 'Smart Water' may or may not work with your grains. Water kefir thrives primarily on sugars and minerals and may even react negatively to vitamin-infused waters. Save some extra grains and test before trying something like this on your whole batch.

Does it matter what water you use?

Water is one of the crucial ingredients for water kefir. What water you use will make a difference. Since most of us don't have the equipment to test what is in our water, let alone on a day-to-day basis, this usually requires some experimenting. Water kefir generally prefers a nutritious highly mineralized water (also called hard water, or mineral water / spring water if its from a bottle). Soft water, filtered water, carbon-activated, ionized or otherwise altered water does not seem to encourage the same amount of growth or vitality in our observations. Reverse osmosis water has in most of our observations led to eventual kefir grain death even. It just doesn't contain enough of the various and vital minerals found in normal tap, spring or mineral water. Also, chlorine can be an issue and should be avoided if possible. To remove some of the chlorine you can let your water set out (without a lid) and it will evaporate in about 24 hours. Some forms of chlorine such as chloramine won't dissipate as easily. If you are unsure what your tap water contains, contact your local water facility for details.

Do kefir grains have a water preference?

Because there are many other variables like the fruits and sugars you use, it's difficult to suggest one water over another. However, kefir grains do usually fair better in mineral-rich water (mineral, spring, well, or hard water). Reverse-osmosis seems to damage them over time and is not recommended. They also do not like heavily chlorinated or otherwise chemically enhanced or treated waters. Water kefir grains will use what they can get, within the combination of the sugar source, fruit source and water source. If you want to rely more heavily on your water, then mineral-rich is preferred - in this case your grains will most likely require less help from unrefined sugars (like molasses, brown or rapadura for example) and less help from dried fruits (like coconut or apricots).

What about reverse-osmosis water?

Reverse osmosis water has in most of our observations led to eventual kefir grain death even. It just doesn't contain enough of the various and vital minerals found in normal tap, spring or mineral water. It is what we like to call 'processed' or 'refined' water, basically an empty water devoid of its normal nutrients and properties, much like white sugar is compared to whole cane sugar. It's an unbalanced and empty nutrient.

What about well water?

Water Kefir grains typically love well water as it is usually high in good minerals - usually much more minerals than you find in a typical spring water bottle. We have exclusively used only well water for our water kefir grains for many years now. Sometimes, well water can have some interesting things in it or too much iron, but most will generally provide good water for your water kefir grains. If you are concerned about harming the grains, have your well water tested for contaminants or compare to store-bough spring or mineral water.

What is the optimal water to sugar ratio?

The optimal ratio is about 3-10% sugar-water solution, which is roughly 1 tablespoon sugar per 1 cup water (6.25%). In the summer you may find that a little more works best, such as 6 tablespoons per quart (9.37%). This is in reference to using about 1 tablespoon's worth of grains for every cup of water.

Is metal a safe material to use?

This is a much debated topic without a firm diagnosis. There have even been some studies that show that fermenting milk grains (which are similar to water grains) in aluminum didn't seem to inhibit their growth. But it is advised not to use such metals as iron, tin, copper or aluminum. Stainless steel is considered safe by most people. The real concern here is whether the grains have a prolonged contact with the metal. It is never advisable to ferment your kefir or store your kefir in a metal container. Acidic foods and liquids (such as kefir) can have a leaching effect on metal when maintaining prolonged contact. If you are simply using a metal spoon to occasionally stir or retrieve your grains, or a metal sieve to separate your grains from the kefir, this has never shown to be a problem at all. Many people use either a nylon, plastic, wood or stainless steel strainer - all materials proven to work equally well. If you are using a product that recommends not cooking or using acidic ingredients such as tomatoes, then it is also not advised to ferment or store kefir in it either.

What type of container can I ferment and store my kefir in?

Glass, ceramic or a food-grade plastic is recommended. Metal can leach when in constant contact with acidic liquids (such as kefir). A thick glass (such as anchor hocking, ball or kerr) with a rubber seal is recommended to lessen the hazard of stored kefir exploding.

Do utensils need to be sterilized for kefir similar to making yogurt?

No, unlike canning or making yogurt, kefir does not require utensils to be thoroughly sterilized. Just use clean hands and utensils, preferably ones that are designated to just kefir related tasks. Expecially if you are culturing viili, make sure the utensils to do mingle - cross-contamination is very easy between these two cultures. There is no need to boil, use bleach, vinegar etc - a simple hand wash or dishwasher cycle will suffice. Kefir, by its nature, keeps itself sterilized and clean (inhibits foreign microorganisms quite well)- you will notice that even when leaving a utensil out with kefir on it, it will not mold for quite some time. This is why rinsing your grains is not needed (and actually can upset them a bit) and constantly changing to new jars is not necessary either (a jar change once a week or every 2 weeks is just as effective). Make sure lids and cloths are clean as well, and getting washed (if you use cloth lids or bags to hold the grains, wash and then iron it to clean - the iron adds a nice, sterilizing heat that the washer cannot match).

How much or how little water (and grains) can be used?

Kefir starting out (after being stressed during mailing or from being dried) will usually ferment between a 1:16 - 1:18 ratio. This means 1 tablespoon grains will ferment about 1 cup sugar-water, and in time it may increase to about 1:24 (1 tablespoon grains in 1 1/2 cup water) to even 1:32 or more (1 tablespoon grains in 2 cups sugar-water) in the summertime perhaps. Try using a ratio of grains to sugar-water of about 1:16 - 1:18 to begin. This ratio seems to always work well, and may need no adjustments at all. Not all kefir is the same; some kefir grains will ferment much quicker than others. We have seen some grains so sluggish it took 1/2 cup of grains to ferment 4 cups of sugar-water in 48 hours (especially in the winter). Both have benefits - if you have fast grains, you will need less and it could possibly ferment in about 12-24 hours (especially in the summer). On the other hand, if you have slow grains, you can use more, and have kefir every 24-48 hours (easier to keep up with). As long as they are growing and producing kefir, the speed and strength is more of just the character of the particular grain you have, and not something to worry about either way. If your kefir is too sour before your usual straining time, simply adjust to less grains, or more sugar-water, or strain it every day instead of every other day. If you use too much sugar-water and not enough grains, the solution may go off before the kefir grains have a chance to ferment it though, so be sure to understand how much it can do, and gradually increase from there. To get lots of kefir quickly with just a few grains simply keep sugar-water without straining. The finished kefir will act as somewhat of a starter along with the grains, quickly turning each addition to kefir. For example, with 1 tablespoon of kefir, you may pour in 2 cups of sugar water, wait 24 hours, add in another 4-5 cups then in about 12 hours you can top it off with another 9 cups and you will have a gallon of kefir in just about 2-3 days.

How much or how little kefir can I make?

This is entirely dependant on the amount of grains to water that you are using. There is no specific amount, nor any kind of limit. If you would like only a cup of kefir a day, simply use just 1 tablespoon of grains. If you want a gallon a day, you will need to use around 16 tablespoons (or 1 cup) grains.

Do you always have to use the grains to make kefir?

Kefir liquid actually also contains billions of microscopic organisms that are effective at making a fermented drink out of sugar-water as well when you stir in atleast 1/4 cup per cup and let sit out or in the fridge for 24 hours. It will dilute and get weaker each time, so its best to start with freshly made kefir (from kefir grains) each time for the freshest and safest ferment. But this is a great option for fermenting other liquids or making a quick batch in a pinch.

Does the water have to be warmed before adding it to the grains?

No, cold water is just fine. Especially in the summer, it will help keep the grains from over-fermenting. Warm water is not harmful (and sometimes helpful in the cold winter months) as long as its not high in chlorine - to get around this problem, you can either fill large jars with cold water (and let them sit for 6-24 hours to let the chlorine gas dissipate) and then heat them in the sink with hot water around them (or a heating pad), or you can boil water and let it cool (boil the water for a few minutes, then let cool, and you can even shake the water in a seal container to incorporate oxygen for the kefir grains back into it, as boiling drives out most gas from the water, including oxygen. Either way will reduce the chlorine. Kefir grains can be harmed by hot water (which has the potential to kill the bacteria and yeast), so keep your water below 80°F / 26°C when adding it to the grains.

How full can I fill my kefir jar?

Its best to do no more than 2/3 to 3/4 full. Kefir needs air space, and it will slightly grow in volume as carbon dioxide gets trapped amongst it while fermenting and expands it. It does not grow as much as milk kefir, since the liquid remains thin though. This is more important if you are putting the lid on tightly, as it can explode if there is not enough available space as it expands.

What temperature does water kefir prefer?

In our observations water kefir successfully kefirs at a wide range of temperatures, with its favorite range being between 65º - 82ºF (18º - 28ºC). 71º F (22ºC) is the most ideal usually. Anything above 86°F (30°C) can be damaging. Kefir can actually still ferment anywhere from 39°F to 86°F (4C°-30°C). This is why it will continue to ferment in your fridge, just at a much slower pace. If you live in a tropical or very hot climate, you may need to make some adjustments so that your kefir isn't constantly exposed to excessive heat (82°F/28°C or more). You can try fermenting in the fridge during the day, and letting it sit out on the counter during the night. Or you can immediately place the kefir in a thick cooler after pouring cold water into it (or add cool water or a little ice pack in the cooler to help keep it cool).

Should I put a lid on Kefir?

Putting a lid on kefir while its fermenting will increase the carbonation (fizziness) of the final kefir quite a bit. Kefir grains thrive when exposed to oxygen and seem to do slightly better when the lid is breathable (a cloth, paper towel, etc). Also, it is safer to cover it with a breathable lid because of the risk of built up carbonation exploding the glass. This can and does happen, usually when a bottle is forgotten, or filled too close to the top. Make sure that if you're putting a tight lid on your kefir while its fermenting that you don't fill the jar more than 2/3 full. Just like soda, kefir will expand if enough carbonation has built up and not enough space was left; it will burst and climb right out of the jar when you open the lid. You can also achieve a happy medium by loosely placing the lid on the top to make it a tighter fit than a cloth would be, but still loose enough that air can escape. To avoid fruit flies, be sure that whatever lid or cover your are using, that it is secure and there are no large holes that a small fly (or other floating things like dust or pet hair) could easily get through. Keep in mind that when you bottle and store your strained kefir, the carbonation will increase at that point too, so it isn't necessary to try to achieve carbonation during the actual fermentation when the grains are in it. We like to use a cloth and once our kefir is in the fridge for a couple days the carbonation kicks right in!

Does Kefir need a breathable lid?

Kefir functions best when it has oxygen. When you try to go anaerobic (no oxygen), you will be getting basically a carbonated kefir wine. Some people prefer to ferment with a tight lid to increase the carbonation (though this can be done at a later process). It also increases the risk of explosions when the lid is tight. We always ferment ours with a cloth of some kind as the lid.

Can you use kefir liquid as a starter (instead of the grains)?

Kefir liquid actually also contains billions of bacteria and yeast that are effective at making more fermenting liquid if you add some fresh sugar or fruit juice and let sit out or in the fridge for atleast 24 hours. It will dilute and get weaker each time, so its best to start with freshly made kefir (from kefir grains) each time for the freshest and safest ferment. But this is a great option for fermenting other liquids or making a quick batch in a pinch (and to protect the grains themselves from harmful fruit juices that could hinder their growth).

Can kefir be in direct sunlight?

This is not really recommended, as it can more easily encourage other bacteria to grow if it heats up the jar too much (just like a fish tank in direct sunlight is more difficult to keep clean). Although if there is not an option, it shouldn't usually cause a problem. In our observations, water kefir placed on the window sill didn't prove to be any different or run any increased risk of contamination than our others placed in our darker kefir cabinet. It can also cause increased yeast or an uneven ferment. For now we still recommend kefir grains be placed in indirect light or dim light (such as in a cupboard) or a cool corner of the kitchen counter.