Cold soba noodles, “zaru soba” in Japanese, is a light, refreshing meal that’s served more often in the summer. Want an easy, 10-minute recipe for chilled soba when it’s too hot to cook? Are you looking for a not-so-heavy alternative to wheat pasta? This dish is ideal for noodle-lovers who are trying to eat healthier and lose weight. 

In this post, you’ll learn everything you need to know how to make cold soba noodles at home. You’ll see that can easily incorporate these Japanese noodles into your healthy diet. Plus, you’ll learn how to eat soba at a Japanese restaurant like you actually know what you’re doing. 

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zaru soba on bamboo plate

Why are soba noodles healthier than wheat pasta?

Soba noodles are made from buckwheat flour. But don’t be fooled by the name.

Buckwheat isn’t a grain…

which means buckwheat isn’t wheat either. 

The edible portion is actually a fruit seed from a plant that’s related to rhubarb. 

It’s a superfood, high in essential nutrients, protein, and fiber. 

Buckwheat also contains more minerals and antioxidants than most grains.

Soba is lighter on carbs and has more fiber than most traditional pastas and noodles.

One cup of soba noodles has approximately 24 grams of carbs. To compare, one cup of refined wheat pasta has about 43 grams of carbs. 

Are soba noodles gluten-free?

Having “wheat” in name buckwheat confused me at first.

I hope I can make this part clear, especially for people who have Celiac’s Disease or a sensitivity to gluten.

Buckwheat is gluten-free, on its own.

But please be aware that most packaged soba noodles also contain at least some percentage of wheat flour. 

If this is a concern for you, I go into more detail about soba noodles with no added wheat flour below.

Note of caution: the buckwheat in soba causes an allergic reaction in some people. 

cold soba noodles with tsuyu sauce

100% Buckwheat – these Soba Noodles are even Healthier

Making homemade soba noodles by hand with a low ratio of wheat flour is extremely difficult.

That’s why most soba noodles at restaurants in Japan contain at least some wheat flour. 

The gluten in wheat flour makes it easier for the dough to hold together.

The soba restaurant where I ate lunch yesterday uses the ratio of 90% buckwheat and 10% wheat flour to make their handmade noodles.

Soba noodles made with 80% buckwheat and 20% wheat flour are called hachi-wari soba (八割そば). Hachi-wari means 80% in Japanese.

100% buckwheat noodles are called juwari soba (十割そば).

Until recently, I didn’t even know that 100% buckwheat soba existed.

It instantly became my new favorite wheat-free noodle option.

Juwari noodles are more full-flavored, nuttier in taste, and grainy in texture.

I use juwari soba noodles when I cook at home because it’s the healthiest option.

Juwari soba suits my low carb diet.  And with no added wheat flour, these noodles are naturally gluten-free.*

If you like the taste and texture of whole wheat pasta, I’m pretty confident you’ll oodle over these noodles too.

Where to buy 100% Buckwheat Soba Noodles

Once I learned the name in kanji, I often notice juwari soba at high-end supermarkets in Tokyo like Seijo Ishii or Queen’s Isetan

100% buckwheat is a little bit more expensive. 

If you live outside of Japan, you may have a hard time finding good quality juwari soba. 

I just googled “juwari soba” and a few options that are made in Japan do show up. Lately, I’ve been buying this brand from Hokkaido.

If you love every kind of Japanese noodle, you might be interested in Kokoro Cares “Yui” Care Package, which contains juwari soba, matcha soba, and five-grain udon. 

*Note of caution: I’ve yet to find certified gluten-free juwari soba in Japan. The options available may be from a factory where wheat is processed. Please consult your doctor.

soba dipping sauce tsuyu with wasabi

What is Zaru Soba ? 

This is the simplest dish on the menu at any soba restaurant in Japan. 

On a sweltering hot day like today in Tokyo, 34 C ( 93 F), it’s exactly what I’m craving for lunch.

Mori soba is plain noodles served in a basket with a chilled dipping sauce on the side. Add a sprinkling of nori (dried seaweed) on top, then it’s called zaru soba.

Both come with a garnish, usually thinly sliced scallions (negi= spring onions) and wasabi, on a small dish resting above or next to the dipping sauce.

That’s it. Simple is best.

A Very Brief History of Soba in Japan 

Juwari soba, that I mentioned above, is considered the most traditional soba noodle.

Over 300 years ago, when soba noodles were made from 100 % buckwheat flour, they were prone to easily breaking apart.

Because of the noodles delicate nature, they were steamed and s