Wednesday, 25 January 2017

Fermented foods and FODMAPS

By Shirley Webber (Research Dietitian)



Over the last few years, a number of “it” words have emerged in the area of gut health, such as microbiome, gut microbiota, prebiotics, probiotics, culture and fermented foods. With this emergence has come an increasing interest in fermented foods.
Fermented foods are those that have gone through a process of fermentation where a carbohydrate is processed to alcohol or organic acids by adding microorganisms (yeast or bacteria) to ferment the foods. This process has been used for centuries to preserve foods.  Manufacturers of fermented foods make a lot of claims regarding the benefits of eating fermented foods, for example, that they foster the growth of beneficial microbes, called probiotics that assist in maintaining a healthy balanced microbiome.

But are the claims regarding the health benefits of eating fermented foods valid? There are a limited number of clinical studies that have been done investigating the health benefits of fermented foods and the answer is not quite clear. While we know that particular foods, prebiotics and probiotics, or the absence of these foods can alter a person’s gut microbiota, we still don’t know exactly how they affect our long-term health. Therefore, it is difficult to say if consuming fermented foods will promote the growth of good bacteria in our gut. This uncertainty makes this emerging field of study a very interesting area of science to be a part of.

In response to the growing consumer interest in fermented foods, the Monash University FODMAP team has been very busy, testing the FODMAP content of fermented foods, as well as looking for answers on the roles of bacteria in health.

Our testing yielded some very interesting and somewhat unexpected results when we compared the FODMAP rating of fermented and raw foods. As you can see from the table below, while the FODMAP ratings of some foods were the same whether they were raw or fermented, some were drastically different, for example common cabbage as a raw ingredient is low in FODMAPs in a 1 cup serving however when fermented to produce Sauerkraut this 1 cup of fermented cabbage is high in the polyol, mannitol. These results remind us that we cannot predict the FODMAP rating of foods without testing.



Raw ingredient

FODMAP rating

per serve

Fermented ingredient

FODMAP rating per serve

Common cabbage

Low

Fermented cabbage i.e. Sauerkraut

High

Red cabbage

Low

Red cabbage sauerkraut Rotkohl (fermentiert)

Moderate

Milk

High

Yoghurt

High

Goats milk

High

Goats yoghurt

Low

Milk

High

Kefir

High

Soy beans

High

Tempeh

Low

Spelt wheat

High

Sourdough spelt bread

Low

Mixed vegetables

High

Pickled vegetables

High

Onions

High

Pickled onions

High

Small cucumbers

Low

Pickled gherkins

Low


** Check the app for appropriate serving sizes and their FODMAP rating.

There are a number of low FODMAP, fermented foods to choose from, e.g. one standard serving of  goats yoghurt, tempeh, sourdough spelt bread and pickled gherkins are low in FODMAPs. There are also smaller serving suggestions for sauerkraut, fermented red cabbage and pickled vegetables in the Monash University low FODMAP app at which these foods are low in FODMAPs. While these are safe to include on a low FODMAP diet, we don’t yet know whether including them in your diet will yield particular health benefits. As always, we remind you check the app for serving sizes and FODMAP rating.

We are constantly testing new foods and this is made possible by sales of our smartphone app that fund our research. Keep an eye on our blog for new foods that will be added in the coming weeks.

33 comments:

  1. I wonder whether the difference in your result, for example common cabbage vs sauerkraut is simply due to the difference in the amount of starting material. Ie to make 1 cup of sauerkraut would take much more than 1 cup of common cabbage?

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  2. Excellent question! I also wonder about sourdough einkorn... my kids seem to tolerate that so much better than sourdough spelt.

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  3. It is due to bacterial fermentation. The bacteria produce polyols when breaking down the cabbage..

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  4. I love that app sales are funding new research! I was wondering why it was $10. I bought it on both ios and android. I would consider a subscription model if I knew I was funding new research.

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  5. I'm so glad this has been published. I've had a lot of problems lately and I've been pounding sour kraut thinking it was good for me!I'm curious about coconut milk kefir and rice-flour based sourdough. Now that I know the app sales fund research, I would totally pay for a subscription!

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    1. Shane, I find that I can tolerate coconut kefir (brand: Amphore) but cannot tolerate the smallest amounts of coconut milk.

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  6. I never realized it before, but I always loved sauerkraut and it always made my stomach upset.I always though it was normal, kinda like eating beans gives you gas.

    I'm also wondering what's the issue with kefir? Is it just lactose? Store bough kefir is 99% lactose free. I also make my own, with live kefir grains. I have no issues with kefir whatsoever.

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    1. Hi there,

      Saukraut is high in the FODMAP, mannitol (a polyol), however small serves should be tolerated. See the monash app for serving sizes. Kefir contains lactose, but great if you tolerate! You only need to exclude foods and FODMAPs that are poorly tolerated.

      Good luck,
      Jane

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  7. According to your app, onions and small pickled onions are high fodmap, but Large pickled onions Are low fodmap. Can you tell me why there is a difference between large and small pickled onions. Both are onions and both are pickled.
    Thank you

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    1. Hi Ann-Marie,

      The small onions are the baby cocktail onions with the large being the general "normal" size onions. We expect that the FODMAP content of pickled vegetables is lower than fresh vegetables due to the leaching of sugars into the pickling liquid. This is possible because oligosaccharides are water soluble. It is possible that the acidity of the pickling may allow increased leaching of the carbohdyrates- although this has not been fully explored. We believe that the cocktail onions have not been able to reach this same level of leaching due to its compact size and that its processing methods. They are just placed in the onion rather than being processed in the vinegar. This has been an interesting result and not particularly one that we expected and therefore our team will be investigating this result further.

      All the best,
      Monash FODMAP.

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  8. I was wondering if the high rating for Kefir was due to its lactose content even after fermentation. Kefir has received alot of good press lately; is there some form of it that can be incorporated into a FODMAP diet, i.e coconut milk, lactose free?

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  9. Can you test black garlic (fermented garlic) please???

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    1. Hi Jodie, thank you for your suggestion, I will pass this on to the food testing team to consider in future. All the best, Monash FODMAP

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    2. I'd be interested too.

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    3. I'd like to know about black garlic too - wonder if the Fructans get 'digested' in the aging process?

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  10. I would like to know if goat's milk KEFIR is high, moderate or low fodmap - goat's yoghurt becomes low fodmap where cow's does not. .. Would kefir be the same?
    Thanks! Loving the app by the way.

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    1. Yes please I would like to know this too, been taking it regularly and will stop till I find out, as my symptoms seem to be worse. Eradicated other things, but not this.

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    2. Yes, I'd also be interested to find out if goat kefir is low fodmap. Thanks for the app too. It's so useful.

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  11. How does goat's milk kefir compare? Being as goat's yoghurt becomes low fodmap (where cow's does not), i'm wondering if kefir does similarly.
    Thanks for all your great work! I am loving the app.

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  12. Before my doctor told me to go on a FODMAP diet, I have had stomach and digestion issues my entire life. I miss gluten, love dairy and have a hard time finding lactose free, and am a garlic lover. This diet has been hard. My naturopathic healer told me to try organically produced fermented things to boost the sad immune system living in my gut. I purchased the app but it isn't great for Americans (measurement issues and items we dont have here are listed) and many things are missing.

    The biggest issue for me is what to drink? I'm addicted to caffeine and was a huge soda drinker before this. Some sodas now are sugar and not high fructose corn syrup but still not the best option probably. Who knows- the app does not address.

    Fentiman's makes really good, I think organic, natural ingredient sodas. My favorite is the mandarine & seville orange jigger. I wonder if the fermented ginger in the drink is helpful or hurtful?

    "Jigger" is an old English term for good measure which we use when we combine the juice of eight mandarins and the zest of Seville orange in every bottle. Speedwell, juniper extract and fermented ginger botanicals then conspire to stimulate your senses with Fentimans Mandarin & Seville Orange Jigger!

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    Replies
    1. I gave up coffee and all stimulants because they can have an effect on your stomach lining. Try sugar free organic drinks, flavoured water, or make your own water kefir (many recipes on the internet).

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  13. Hi Monash! Could you please advise if Chinese napa cabbage is high fodmap? Thank you so much!

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  14. Hi Monash! Could you please advise if Chinese napa cabbage is high fodmap? Thank you so much!

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    1. Hi there,

      Unfortunately we haven't yet tested this therefore cannot comment on it's FODMAP content. If you would like to test your own tolerance, please see here: http://fodmapmonash.blogspot.com.au/2016/01/testing-your-tolerance-to-untested-foods.html

      All the best,
      Monash FODMAP

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  15. Hello, would it be possible to test sheep kefir and sheep yogurt? thank you very much!

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  16. Hello - can you please test coconut water kefir? There's a lot of non-dairy/lactose kefir's on the market right now.

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  17. Hi all you fodmapers
    Just wanted to pass on something about spring onions. You can grow them yourself in a pot, or if you have a spare piece of garden. There are two ways of growing them. One is growing from seed, which you can buy on eBay, and the other is to buy a bunch of Spring onions, making sure they have some roots preferably. Cut off the green part leaving approximately 4 or more cm of the white . Put them into a jar with some water only about 1 cm, and change water every day. Very soon you will see the green starting to grow again. You can keep this on the windowsill, and keep cutting off the longest green parts as they grow, but I find they do much better if you plant them in a Pot or, in the garden somewhere. Keep them watered but don't drown them, and in the winter you might want to put a piece of white shade cloth that is suited to vegetables, just over the top to keep them a bit warm . I have had some growing now for the past nine months, and have more than I need of the green part. I just cut off the tallest and thickest ones, leaving the smaller ones to become tall and thick. If I could, I would post a photo of them. You can also do the same with leeks, but I prefer spring onions. Mine grow to at least 60 cm, and the Green Park is 50 cm of it. I have about three dozen growning. Probably I will start again and put a new batch in July as I am in a temperature climate. This will vary depending where you are.
    Lastly, you can let a couple grow and flower and when the flower dries, that's the next year seeds. But do cut off the flowers of the rest as soon as they appear, otherwise they will take the nourishment from the leaves
    Does anyone know if there is a way of posting photos here?
    Really hope you find this useful
    Annie

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  18. Hi Monash, what about Greek yoghurt? It's not on the app. Any recommendations of tolerable portion size, or is it a no go if you are lactose sensitive?

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  19. So common cabbage is a low- fodmap food? I have seen it listed as off-limits.

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  20. You mentioned goat based yogurts as being low FODMAP, but not other milk based yogurts. What about coconut based yogurt? Do you have any information about whether that is low or high FODMAP? Thank you.

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  21. Interested in the FODMAP status of goats milk kefir and coconut milk kefir made with milk kefir grains. If these haven't been tested grateful if they could be. Many thanks and keep up the good work!

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  22. I'd also be interested in whether goat milk kefir is low fodmap. Can't find any research on it. Thanks for the app.

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