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Ask Kris: The Scoop on Kefir, Oxalates & Frozen Veggies


Hi Sweet Friends,

Each week you wonderful readers ask me really interesting and thought-provoking questions. They come in all shapes and sizes, in the comments section of my blog, my inbox, and on social media. Since I can’t reply to everyone individually, I thought it’d be fun and useful to pick a few commonly asked questions and start tackling them here, for everyone to enjoy. Introducing….Ask Kris. Today I’m covering kefir, oxalates, frozen veggies and juice/smoothie storage! Let’s get started…

Joanie’s Question: What’s your thinking on kefir? I’m finding that after a month of kefir from organic goat’s milk—my digestive issues have improved tremendously.

Kefir is a tart and even sour tasting cultured dairy (or non-dairy) drink that’s prepared by fermenting milk with bacteria. It’s often—but not always—pasteurized. Kefir is rich in probiotics and is generally kind to the digestive system.

One of the greatest health advantages of kefir is its high probiotic content, which may be the main reason for your improvement in digestive issues (congrats!). As you may have read in my dairy blog, goat’s milk is closest to human milk, is slightly alkaline, and has the least amount of lactose, making it more digestible and a better beverage compared to cow’s milk. But, keep in mind that goat’s milk kefir still contains casein and growth factors which may have a negative health impact. Plus, kefir typically has sugar added to make it more palatable (about 12 grams per cup), so make sure you’re being a food detective and reading your labels.

Non-dairy, unsweetened kefirs such as coconut kefir may be a great alternative. While a coconut kefir doesn’t contain the protein in a dairy kefir, it has a similar probiotic profile, none of the growth factors or dairy proteins found in dairy kefir, and the unsweetened varieties aren’t high in sugar.

You may also want to try supplemental probiotics. I’d encourage you to choose one of the higher quality probiotics like Dr. Ohirra’s, Primal Defense, Healthforce Nutritionals (Friendly Force), or MegaFood’s Megaflora as an experiment to see if it’s simply the probiotic content of the kefir that’s helping you. I talk about probiotics in my gut health blog, and I discussed probiotics with Kenneth Bock, Integrative MD in this Chat & Chew video. Take a peek!

Lastly, if you were drinking cow’s milk before switching to kefir, your improved digestion may be related to what you’ve eliminated rather than what you’ve added. Just an idea! If you’re interested in more veggie-based solutions, a plant-based kefir and/or probiotics may give you the same digestive benefits without the drawbacks of casein and growth factors found in animal-based milks and kefirs.

Patricia’s Question: I love my green smoothies! Should I be concerned about my oxalate levels with all the greens I am digesting?

Oxalates have been a really hot topic lately. Hopefully I can shed some light. Oxalates, which are formed naturally in the body and are also found in the leaves of some plants. They aren’t really a concern unless you’re prone to kidney stones, and even then, the evidence isn’t very strong (study here). But since eighty percent of kidney stones are calcium oxalate stones, nephrologists (that sounds kinky/spooky!) may still recommend avoiding high oxalate foods in individuals prone to them. Recent research points to an alkaline diet (lots of fruits and veggies, minimal amounts of animal protein, and plenty of alkaline water, which can be made by simply adding fresh lemon juice to your filtered water) as one of the most effective ways to prevent kidney stones.

The bigger concern with oxalates is that they bind to calcium in the body, and may decrease calcium absorption. The highest oxalate levels are found in spinach, beet greens, and Swiss chard. Because of their high oxalate content, they are not considered a reliable source of calcium. However, not all greens are high in oxalates. Low oxalate greens include kale, bok choy, romaine, arugula, turnip greens, and others.

When in doubt, rotate! If you love spinach, beet greens or Swiss Chard in your daily smoothies or juices, just rotate kale or other lower oxalate greens into the mix for nutrient variety and to maximize calcium absorption. This strategy also applies if you’re prone to kidney stones and want to be extra special careful (as always, check with your integrative doc to find out what’s right for you).

Sharri’s Question: What do you think of eating frozen vegetables when in a hurry and don’t have any fresh vegetables on hand?

Oh la la I love frozen veggies! They can be an awesome and healthy part of your plant-passionate diet. Once vegetables are picked, they start losing some of their water-soluble nutrients, especially vitamin C and folic acid. Each day, more of these nutrients are lost. So, if our “fresh” broccoli is harvested and transported across the country before we eat it, chances are it’s lost some of it’s vitamin C and folic acid content.

Ideally, we’d be picking our broccoli from the backyard or the local veggie stand and eating it the same day. But for those who don’t have access to fresh produce all the time, frozen varieties are a nutrient-rich alternative. Frozen produce is often frozen immediately after it is picked, and freezing halts the nutrient seeping that happens in fresh air.

Remember, boiling or steaming frozen vegetables will cause some of the nutrients to be lost, so including them in a soup that includes the cooking water will save the precious nutrients that would have gone down the drain.

Mike’s Question: Will freezing my juices and smoothies keep them fresher longer?

I’m often asked if it’s okay to freeze your juices and smoothies, and believe it or not, freezing juices or smoothies in mason jars, ice cube trays, or popsicle molds is a great option, especially if you want your juice etc. to last more than 24 hours. Freezing actually preserves most of the nutritional value of fresh juice and smoothies.

The longer your juice sits in the fridge, the longer it’s exposed to oxygen—causing nutrient degradation and the loss of enzymes. Keep in mind that for juice, the rate of degradation depends on the type of juicer used. Juice made with a centrifugal juicers have a shorter shelf life than juice made with masticating, twin gear or hydraulic juicers.

Here’s a handy chart showing what percentage of nutrients is lost during freezing (and cooking, reheating, etc.). Click here to view chart. It’s important to let your frozen concoction thaw naturally and drink it right away, or have it frozen. Nothing like a green smoothie popsicle on a hot, summer day! Heating or defrosting these nutrient-dense creations in a microwave will degrade the nutrients even more.

Hope that helps!

Your turn: What’s your “Ask Kris” question? Maybe I’ll answer it in the next round!

Peace & curiosity,

Kris Carr

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71 responses to Ask Kris: The Scoop on Kefir, Oxalates & Frozen Veggies
  1. I’m in complete agreement re the oxalate thing – I believe a lot of the research is tenuous. But, because like Kris, I am often asked for low oxalate recipes, I finally put together a cook book of high nutrient, antihistamine and anti-inflammatory recipes that are also low oxalate. I find most people do better with eliminating high oxalate grains, flours, and nuts, rather than the green stuff. I myself had an oxalate issue at one point, but I managed to clear it up through excellent nutrition :) Thanks so much for all the inspiration!!

  2. I was just wondering your opinion on Oils. I was under the impression that we should stay away from Canola oils but alot of healthy recipes calls for it? Even the Earth balance, which tastes so yummy! has it.

    I was told it was one of the most highly genetically modified foods. so, is a no no?

    • Wouldn’t touch Canola oil with a ten-foot pole. Canola stands for Canada Oil or Canadian oil (not exactly sure which one.) Read years ago that is a genetically altered version of the rapeseed plant and rapeseed is toxic to humans. I’m from Canada and it is grown just about everywhere. I’d stay away it and stick to olive and coconut oils, as well as avocados. These oils have passed the test of time.

  3. I don’t do any dairy, but I grow and culture WATER kefir. I have found tremendous digestive benefits (and skin/hair) from drinking water kefir daily. It also tastes much more appealing to me than dairy/milk kefir. It’s more like a lightly effervescent soda…however, you can create it in almost any flavor – ginger ale, raspberry, coffee, guava…you name it! I have gifted many family members and friends with water kefir grains or water kefir beverage…and they keep coming back for more..some cannot explain why, others just say they love it! lol…I’m a huge fan and love my water kefir “babies.”

    • PS- I do also have out a small eHandBook on how to grow water kefir grains..the book comes with my grains when purchased…but is available solo if someone just wants to know more about how to make water kefir.

      • What’s the name of your book and where can ppl find out about it honey?

        • Jo said on March 25, 2014

          I love making my own water kefir! It’s so easy and a great way to get probiotics. I got mine and the how to from

        • Hi Kris – My Water Kefir Handbook can be found here – (just scroll down to the “Water Kefir Handbook”). I also culture organic grains and there is a link available to my storefront where grains are sold.

          I love your site, Kris and think your energy and spirit are amazing. Thanks for all you do!


        • OH…nd if you use the 1st ferment water kefir (before you put fruit in it) makes an awesome rinse for your hair and face. I pour an 8 ounce bottle into my h air and let it sit while I shower, shave, etc…really cleans your hair…..and leaves is lovely. My own daughter commented on healthy my hair looks since I started drinking and shampooing with WK! Love it!

    • I LOVE water kefir!! I use fresh ginger in mine and drink a ton! I use raspadura sugar, molasses, himalayan pink salt, and homemade vanilla extract in mine, along with slices of fresh ginger. I culture it for 48 hours and then put it in the fridge as a new batch starts culturing…. I do a half gallon every two days. YUM. I actually have not tried making any other flavors because I love the recipe I am using so much, why try something new (ok I admit, I am fearful of change, haha).

      I switched from milk kefir to piima yogurt recently, and still do my sauerkraut, I have a batch going now. :) Probiotics are life changers for many people :)

  4. Thanks a lot for these answers ! I love that freezing juices and smoothies keeps it all good, meaning I’ll be able to make them from fresh produce then freeze the extra, win-win !

    My ask Kris question : what type of hair dye do you use ? I’ve been researching and testing a few organic hair dyes in the last couple of years without great success (white is only slightly tinted)… I’d love to know your take on this. Thanks so much for everything that you do/share/are :-)

  5. Hi Chris,
    I always thought that frozen fruits are the better option when you can’t get absolutely fresh, but I lately saw a (Danish) television program about imported strawberries and blue berries and from that program I learned that the amount of Vitamin C is pretty much cut in half when you freeze your fruits, because Vitamin C doesn’t tolerate frost very well. That means you get much less of the good stuff if you buy your fruit frozen or freeze it yourself like in a popsicle. What do you know about that and is my information correct?

  6. What about juicing for those with hypothyroidism? I’ve read it’s best to avoid certain greens. How can I get the best nutrition from my juice if I’m hypothyroid?

    • Hi Ellen,

      Andrea Beaman wrote an article about this. She mentions in the comments section that Romain and Iceburg lettuce are the safest to juice for thyroid issues. I’d stick to Romain, since I don’t think iceburg is all that beneficial. Here is the link:

      • I too have Hypothyroidism and I’m just beginning to do A LOT of research on eating the right foods. I was surprised to find that Kale and Spinach are not good for people like us. Even strawberries are bad. Those are 3 main ingredients in a lot of smoothies…LOL! Its a learning process and I’ve created a list of good/bad food and the bad definitely out weighs the good. I also just started reading Kris’s book “Crazy Sexy Diet”.

    • Great question, Ellen! We checked in with our Health Editor, Jennifer Reilly RD to answer your question:

      You’re right that if your thyroid is already underactive, you may need to limit your intake of raw cruciferous veggies (kale, broccoli, collards, etc.). I’d recommend having cruciferous veggies in their cooked form since cooking deactivates about a third of the goitrogenic compounds, and then juicing other greens like spinach and romaine. Plus, you’ll want to make sure that your diet is rich in iodine, as some research points to goitrogenic foods as being a problem for people with hypothyroidism only when iodine intake is insufficient. For more info on this, check the Goitrogens section in our thyroid blog:

      Team Crazy Sexy

  7. Hi Kris – loved the Q and A! I’m interested in the chart that you mentioned at the end (about how many nutrients are lost with freezing etc.) but I don’t think the link is working. Could you perhaps post that? Thanks!

  8. Hi kris,
    Thank you for the amazing work that you do!
    My question is about iron. My blood work consistently shows that I’m iron deficient and anemic, even though I eat spinach, and on occasion pasture-raised/organic/grass-fed sources of poultry and beef.
    Is there a supplement you’d recommend to get my iron levels back up?

    thanks so much!


  9. Stephanie, have you ever been tested for celiac? My sister was chronically anemic for years before she learned she has celiac. The iron and folate from diet and supplements could not be absorbed due to the compromise in her colon. Now that she is gluten-free, her anemia is gone and she feels worlds better! Best of luck.

    • Thank you so much! That’s interesting and very good to know! I actually cut gluten out of my diet about 2 years ago.
      I have a very heavy period so I think it may have something to do with that?

  10. Thanks for this! I LOVE that freezing juices and smoothies doesn’t kill all of the good stuff – as the mom of a toddler, I’ve been having trouble figuring out getting some time with my juicer on a daily basis!

  11. I was interested in your reply to my kefir question Kris. Actually, prior to making my own kefir, I wasn’t consuming any dairy products. But I’ve found that adding goat’s milk kefir and cultured vegetables and kombucha to my diet has made a huge difference. I’m culturing the milk myself so there’s no added sugar and the goat’s milk source is completely organic and thankfully, has no growth factor involved. I don’t consume dairy other than the kefir because I’ve found I can’t digest dairy unless it’s cultured. But the kefir and cultured veggies have helped me digest everything much better. Thanks for your response.

    • Joanie — you are doing everything right — don’t worry about those folks who are “anti-dairy” lol. It sounds like you have a great source of organic goat milk. You are very lucky. :) You will be getting a lot of benefits from this, and even more if it is a raw goat milk source.

      The kefir, combined with the cultured veggies, you are on your way to healing your gut…. have you looked into making homemade bone broth as well? The gelatin and protein aminos in the bone broth will help heal the lining in your stomach as well.

      It is amazing what food can do for you! :)

  12. I love this! I was wondering the same thing about frozen veggies, freezing my smoothies and kefir! Thanks so much for clearing this up! I also find that frozen veggies are cheaper than fresh a lot of the time. So that’s a good way for me to save a little $$ while still getting good nutrition. Thank you thank you!

  13. Hi Kris

    Thanks for sharing all that info. I have read a lot about oxalates and fibromyalgia/CFS. What are your thoughts?

    • Hi Mich! Here’s what our Health Editor, Jennifer Reilly RD had to say about your question:

      While there aren’t any scientific studies testing a low-oxalate diet to treat fibromyalgia or chronic fatigue, there’s some anecdotal evidence that limiting oxalates may help alleviate some of the symptoms–same with a gluten-free diet. If you’re curious, you can always try a low-oxalate regimen (avoid Swiss chard, beet greens, and spinach while enjoying kale, bok choy, arugula, romaine, turnip greens and others) for 30 days and see if symptoms change. All of us react differently to different regimens, and it may be worth a shot.

      Team Crazy Sexy

      • Mich said on May 28, 2014

        Thanks so much for answering my question. I have now tried a low oxalate and a no oxalate diet. Neither has helped my symptoms and the no oxalate path is impossible to follow ! I guess this diet may help some with fibro symptoms but not all of us. Love the blog.

  14. Another great option for non-dairy kefir, is coconut water kefir. Here is a great company that I use:

  15. I love all the tips you share in this Q&A! I’ve been freezing my green smoothies (I tend to make too much) and re-use it instead of ice when I make a new batch.

    It’s also priceless to see my fiancé’s face when he reached for ice but gets a tray full of green cubes :)

  16. Couple of things…

    1. When you make your own kefir, you don’t have to worry about excess sugars. The culture eats up the lactose (so even lactose-intolerant people can drink it) and you can make it with healthy raw milk.

    If you do so, you can use the excess culture (kefir grains) to culture non-mammalian milk like coconut milk, almond milk, etc. But if you use all your grains culturing non-mammalian milk, the grains will slowly starve and die.

    If a person is worried about their healthy dairy consumption (because of allergies, for example) then water kefir is a good alternative. While it is fed with sugar, you can use healthy alternatives like maple syrup, molasses or even pure sugar — sucanat – with tons of minerals — or you can even use fresh juice. The culture eats the sugars so that there is barely a hint of them left.

    2. Oxalates. For those of us who get a LOT of digestive pain when eating high oxalate foods, it is more than just worrying about whether you get kidney stones or not. It is a real issue.

  17. Hi!
    I’ve been making green juice since January and recently saw a show on Dr. Oz saying that too much kale may not be good for us…something about it being a goitrogen and maybe affecting thyroid. Can you please explain this to me. I am now a little afraid to be drinking my green juice! :(


  18. Hi Kris. Like you, I have been diagnosed with an incurable form of cancer (Stage 4 Her 2 Positive breast cancer). Fortunately it is currently under control and I am working on adopting a greener diet and lifestyle. Since I am on a tight budget, and cannot afford saunas or other expensive detox treatments, I was wondering if you could suggest a cheap/affordable way I can get rid of toxins on a daily basis. I have heard that taking Epson salt baths helps. Is this true? If so why and are there any other methods?
    Thank you for your time in advance.

  19. Hi Kris,

    First, let me thank you for all the valuable and inspirational posts, etc.! You have been a great source of information for me in my first year as a Vegan, and I have enjoyed many of your recipes…in fact, I am addicted to your Kale Salad!!

    My Veganism began with my love for animals, and a light bulb moment of connecting that love with the reality of choices about what was on my plate. After digging into as much information as I could, I learned that I was also doing good things for the environment and my health! Yeah!

    I am 65 years old, and am wondering if there are any special nutritional concerns I should learn about because of my age. I feel fantastic, but I have lost 20 pounds that I did not need to lose! Adding more calorie dense food now, such as more beans, and avocados, and I am not dropping more weight, but not gaining. Any advice?

    Thanks for all you do!

  20. thank you, Kris! You’re so helpful + fun! xo

  21. Does drying on that chart mean `dehydrating’ as in raw foods?

  22. Thank you so much Kris, your knowledge is your gift to us, I have leaned and benefited from your articles, and of course, your books and recipes. Keep up the great work.

  23. Great post Kris! Love the idea of “Ask Kris” regular column. You’re awesome. Keep up the great work!

  24. What about eye health? I eat carrots and spinach every day because I have eye issues. Is this enough?

  25. Lovin’ the Q&A Kris!

  26. I’d love to know what you like for health and beauty aids, what kind of make-up, soap, shampoo etc do you use? You always look great!

  27. What a great idea. Just wanted to mention you can make water kefir very easily too,lots of recipes on the web. I am now concerned about my spinach intake I have about 2 cups a day raw chopped up on my evening meal.

    My question:

    Is cooked potato a good food or not? And how much is too much?

  28. Hi Kris. Thanks for all the wonderful info! I too have a question about green juicing/smoothies with hypothyroid. Much of the information out there seems to be centered around eating raw green smoothies/juices and their effects on hypothyroid. I am a 3x cancer survivor and love my green drinks to help keep my immune system strong. What’s your take on it? <3

    • Also…the goitrogenic effects from what I have read are mainly a problem with hypothyroid caused by low iodine, so I’m not sure then if it’s just the raw factor…

  29. Thanks for adding this section! I love it!

  30. Regarding oxalates, I have read that although they may bind with calcium and iron, if you take them with a fruit like an orange or any form of vitamin C that this helps counteract the effects of the oxalates.

  31. Hi Kris, thanks for this post this is really interesting as I just love my green smoothies every morning. Plus I’m just about to embark on making my own Kefir, as although I’m dairy intolerant I can tolerate Kefir made with raw goat milk. In fact, it is fantastic for my digestion. So glad you’re posting about the benefits. Thanks!

  32. I love this post! So much great information in a quick easy way to understand it. I hope you’ll do more blog posts like this :)
    If so I’ll through a question out there (you might have already answered this sorry if you have I’m new to following you).
    When cutting out refined sugar what are some basics I should follow when using alternatives like stevia, agave, maple, dates and honey? Sugar makes my skin brake out (being 29 I’m so over having acne) I’ve been dairy and GF for 2 years now and a vegetarian for 11 years but still have brake outs and know it’s from sugar. Just looking for some advice on how to cut it out and still enjoy the sweetness of life. Thank you! xox

  33. This was very timely! I am curious about the Crazy Sexy Team’s take on phytates. Not only had I been reading a lot about oxalates a lot lately, but I’ve also been reading a lot about the phytates in beans, grains, legumes and nuts lately. The Paleo folks (and some others) recommend limiting, if not completely cutting out, foods from these groups (nuts, legumes, beans and grains), in part because of the phytates (or enzyme inhibitors). The phytates are designed to protect the seed/grain/bean from sprouting in an unfriendly environment. In the human digestive tract, if not appropriately sprouted, soaked or roasted (I’ve seen one site that says you have to do all three!), these foods can rob your body of minerals eaten in that same meal.

    What is your take on that?


  34. Kris one question on juicing, I have been doing my smoothies but I am
    Very interested I to juicing, the problem is a don’t have a juicing machine (I do have a blander) could I blend the ingredients and
    The strain them? Would that work as well?thank you and thanks for being such an inspiration :)

  35. Hi Kris I have been doing green smoothies lately, but have hear that juicing is much better when we want our bodies to absorb all the vitamins and minerals, two questions about this, I don’t have a juicer but I do have a blender is it the same to blend the ingredients and then strain them? And if yes here is the second question, what can we do with the fibers that are left from this process.

    Thank you so much for all your shared jnowledge and for being such an inspiration :)


  36. What are your favorite water purification systems? I am interested in stand-alone solutions that eliminate Pharma and volatile organic compounds (VOCs) as well as all the other bad stuff. Thanks Kris!!!

  37. Do dried goji berries have the same nutrient content as fresh?

  38. I was wondering if dried goji berries have the same nutrient content as fresh. I live in Ohio and dried are the only ones I have found.

  39. Really helpful! I’ve been hearing a lot about coconut kefir lately and I honestly had no clue what it was or where to get it/how to make it. Maybe I’ll go and try this today …

    Thanks for sharing! :)

  40. Wondering what you think of both rice bran oil and grapeseed oil.
    I have read good things about both and use them in addition to olive oil and coconut oil.

  41. Hi, I have a poor digestive system such as bad breath, constipation and I have trouble losing weight, my sister said if I bad digestive system and eat healthy food it wont help unless my digestive system is healthy. I was wondering if youre diet would improve my digestive system and assist with weight loss?

  42. Kris,
    I keep reading about bone broth for healing leaky gut. Do you know of a vegan alternative to bone broth?

  43. Each time I try to switch to this way of eating my stomach kills me with pain when I eat beans. I soak them as you directed they still are not something my stomach can handle. My Dr even tested me thinking I may have a bean allergy. But nope. Not the case. I am so ready to turn my life over to this way of eating. Can you help with how to transition when beans aren’t easy for me to eat. Is there any way to change this with time ?? Thank you for your time. I am feeling hopeless if I can’t add this main ingredient to my eating.

  44. Hi, Kris,
    I want to be kind to my liver, which was recently resected due to cancer. What foods do you suggest for liver health? One website I went to suggested grapefruit and lemons, but no limes or oranges. I can get organic oranges at my local grocery store all winter long, but not the grapefruit and seldom the lemons. What is your list for liver health? Also, where do you get burdock root, which I saw in your cookbook?

  45. Thanks Kris, super informative! Much appreciated.

  46. Hi Kris, thank you for sharing this post and shedding some light on these subjects! I think a major issue in the cleaner eating movement is that we can fall into the trap of seeking perfection. Guilty myself of sometimes spending more time researching or thinking rather than acting. When I find myself in that situation, I just take a step back and re-center. I think good nutrition should be enjoyable and simple. If we become overwhelmed and anxious then we are depleted rather than nurtured. There is no in-between.

  47. Hi Kris, In 1976 at 25 yrs. of age with a 4 mo. old daughter I was diagnosed with Thyroid cancer. Surgery removed my thyroid and a lot of cancerous growth. I began taking synthroid, calcitriol and calcium lactate pills to replace thyroid activity.. Did great until 1998 and a small amount of the cancer cells were found and received a radiation treatment which zapped it all. My daughter introduced me to your books and juicing! I love the smoothies and juices! I am confused by the information I read on certain greens and their effect on thyroid conditions. I am interested in juicing to help keep my system healthy and cancer cells at bay. My gut reaction is that real and raw foods are good for you. Could you shed some light on this question or direct me to any information? Thank you! Marian Johnson

  48. My friend referred me to your website. I am a 75 year old woman who has been told that I will need to have my gall bladder removed. I do not want another operation because the last one I had, they cut an artery and I almost died on the table. I am looking for advice re diet, etc. that might prevent me from having another surgery.

    Thank you in advance for your help.

  49. Why has my constipation got so much worse since starting green smoothies?

  50. After making kefer and smoothies & I suddenly have chunks and it’s very fermented. I tried culturing for less time and I didn’t agitate as vigorously but still Have chunks, etc. I’ve been making kefer a coupla times a week for over a year and haven’t changed the way I make it so I’m confused….

  51. Kefir is a fermented milk product that originated centuries ago in the Caucasus mountains, and is now enjoyed by many different cultures worldwide, particularly in Europe and Asia. It can be made from the milk of any ruminant animal, such as a cow, goat, or sheep. It is slightly sour and carbonated due to the fermentation activity of the symbiotic colony of bacteria and yeast that make up the “grains” used to culture the milk (not actual grains, but a grain-like matrix of proteins, lipids, and sugars that feed the microbes.with my best wishes,melissa from