Is Miso Soup Gluten-Free? Get the Straight Facts Now!

For those who fancy Japanese cuisine, it is a fairly common question to ask – Is miso soup gluten-free? In recent years, there has been a rise in the popularity of fermented products such as kombucha, kimchi and tempeh, which have been touted as a superfood to improve gut health. Therefore, the boom in miso, another popular fermented food, has also been steadily on the rise. Miso soup is a staple in Japanese cuisine, but, the base of the miso soup – miso paste – is also used in many other cuisines, especially fusion food. Therefore, this article will explore whether miso soup, and whether miso in general, is safe to eat for people following a gluten-free diet. 

What is Miso Soup?

Miso soup is a traditional Japanese soup made by using a broth of dashi stock, mixed with softened miso paste. The result – a rich, deep-flavoured broth filled with the umami taste of Japanese profile – slightly salty and earthy, with a slightly sweet undertone. In short, it is something comforting and mild enough to be consumed every day and every meal – a dining practice that is commonly seen in Japanese culture. 

So, what is dashi stock?

Dashi stock forms the foundation of many Japanese dishes and is used in Japanese favourites such as ramen, miso soup and my all-time favourite – chawanmushi (steamed custard egg). The stock is usually made with the essential kombu (dried seaweed) and katsuobushi (dried bonito flakes), while variations of dashi will include other ingredients such as shiitake mushrooms and niboshi (dried anchovies).

Depending on individual preferences, dashi can be made with a stronger seafood taste, lighter umami taste, vegan, etc. – it all depends on the proportion of base ingredients used. And these ingredients, in the most basic sense, are thankfully all gluten-free. Can you imagine how navigating Japanese cuisine will be like if dashi contains gluten and ends up on the no-go list? 

See Also: Is Sriracha Gluten Free?

is Miso Soup gluten-free?

The good news is dashi is naturally gluten-free. The not-so-good news is that miso soup may or may not be gluten-free. This is because there could be gluten-containing ingredients in the miso paste – it all depends on what the miso paste was fermented from. All miso is made with fermented soybeans. Alongside these soybeans are many other ingredients such as salt, koji (a kind of Japanese cooked rice that has been inoculated with fermentation culture), beans, chickpeas, millet, rye, wheat and even quinoa.

Therefore, not all miso is gluten-free, and this is so if it has been fermented with gluten-containing grains – most commonly barley, wheat and rye. 

Is Miso Soup Gluten-Free: Which Type Of Miso?

Gut health is especially important for those following a gluten-free, as gluten can cause havoc on the digestive system of those who are gluten intolerant or gluten-sensitive. Therefore, miso is a good addition to one’s diet – but let’s not let the irony be lost if we inadvertently choose a miso paste that creates more unsettling problems for the digestive system. 

There are many types of miso out there – each with its own characteristic and flavour profile. 

Types of Miso

White Miso: White miso is the most popular and commonly found variation of miso paste. Also known as kome miso, this is mild and sweet and takes only 3-4 weeks for it to age. This is usually made with white rice koji and is most easily accessible to consumers. 

Yellow Miso: Yellow miso, also known as shinshu miso, is made by fermenting soybeans with koji made from barley. Since barley contains gluten, it is essential to double-check the ingredients when consuming yellow miso. 

Red Miso: Red miso has the strongest flavour, with the longest fermentation time and more concentrated flavour. The extreme umami taste of red miso also means that red miso can usually be found in food items with a stronger flavour, such as Japanese curry or beef stew. The difference between red miso, also known as aka miso, is that there is a higher proportion of soybeans to grains. So once again, it is essential to make sure that there is no barley or other gluten-containing grains such as wheat in the ingredient list of red miso. 

There are also other types of miso, such as hatcho miso which is only fermented with soybeans, water and salt, mugi miso, which contains barley alongside soybeans. Thus, the wide variety of miso out there may confuse you (and yes, it does confuse me too!), so it is essential to know which type of miso paste is being used because not everything is gluten-free. 

From Japanese Miso Soup to Nobu’s Cod Fish

The tricky part about miso is that not everybody knows what type of miso is being used as an ingredient – honestly if you were to ask me what miso paste is used in my kitchen, I can only tell you that it is miso. Whether it is aka miso or shiro miso or something else, I have no idea. I could bet my money that not every restauranter knows the kind of miso that is used. Hence, it is important to clarify whether the particular miso that is being used is gluten-free or not. To those following a gluten-free diet, it doesn’t matter what type of miso is used – what matters is whether it contains gluten or otherwise. 

My love for miso extends beyond Japanese miso soup. My first foray into the land of sweet-umami miso was when I had miso soup at a Japanese restaurant near my office. Then, I discovered that miso was the missing flavour that adds a layer of depth and profile to many food items. When I visited Osaka, I tried a version of gluten-free ramen that was cooked perfectly, and I’m pretty sure that the secret lies in the miso used in the soup.

But my most memorable miso dish has got to be the Black Cod Miso which I had at Nobu in Las Vegas nine years ago. The pairing of the miso paste with the soft, flaky cod was simply splendid – no wonder it cost a bomb. 

Gluten-Free Miso Based Recipes

For those looking to replicate these delectable miso-based dishes, here are some gluten-free recipes which you can explore: 

●    Nobu’s Miso Marinated Black Cod: With just 5 simple ingredients, this black cod recipe is a close contender to Nobu’s version, at a fraction of the price tag. 

●    Miso Noodle Soup: This is the perfect comfort food for a cold, rainy day. It is also my go-to recipe for when I’m sick in bed and need something nourishing. 

●    Miso-Glazed Chicken Breasts: This is complete-packed with protein and flavour and in my opinion, easy to make for a family gathering. Topped with a side of baked vegetables, one would never know that these chicken breasts are homemade! 

Conclusion: Is Miso Soup Gluten-Free? 

Miso, in its most original form, is gluten-free because it is simply mixed with soybeans, salt, water and rice grains. But different renditions of miso have seen barley, wheat, amaranth and other kinds of grains being used as the catalyst for the fermentation process. Therefore, it is essential to check what ingredients are used in the miso paste before savouring the food. It is indeed a challenge to know what type of miso is used, but with a bit of due diligence and effort, going gluten-free while continuing to enjoy Japanese delicacies is not too difficult.