Articolo disponibile anche in: Italian

Ever had Ramen in broth or stir-fry? Delicious, aren’t they? Whichever way you prepare them, they stay firm and full-bodied, but how is that possible? Simple, their secret is called Kansui 枧水, but How To Make Alkaline Water?

When my journey to prepare Ramen at home began, Alkaline Water Kansui was an impossible ingredient to find except in Asian countries. I didn’t give up and after several searches I figured out what it was and then how to make alkaline water at home. If you are here, your love for ramen is probably such that you want to make delicious ramen at home. Ramen may seem like a simple dish to prepare, but it’s really not, but it’s not impossible either!

What makes a bowl of ramen special, are the noodles, the broth, Tare, oil, and toppings. Today let’s start talking about the first mentioned: the noodles, or rather, let’s see how to get off to a good start in order to get them, in this article I explain what kansui is and how to prepare it at home.

What is Kansui

Kansui is a special alkaline mineral water, also called Lye Water, composed of sodium carbonate, potassium carbonate, and sometimes phosphoric acid. Its pH is acidic, and it should not be drunk at all and should be handled with care.

In the past, this alkaline water was taken from a lake in Mongolia, Lake Kan, from which it derives its name. The waters of this lake, were naturally rich in these substances, so the Chinese used this water to prepare their noodles.

It can be found commercially in liquid, powdered form, or flour with the powder component already in it.

Liquid kansui
Liquid kansui
Kansui powder
Kansui powder
Flour with kansui
Flour with kansui

The Importance Of Alkaline Water

Alkaline Water Kansui is crucial, because it gives that special elasticity and toughness to the noodles, which causes the ramen noodles not to melt in the hot broth. Their yellowish colouring is also due in part to the Alkaline Water. But let’s take a moment to analyze the components that make it up, and here I want to make a point after one of my readers pointed out this very important detail.

Sodium Carbonate is an element identified as not harmful, can be ingested in small amounts, but is irritating if it comes in contact with the eyes, but Potassium Carbonate on the other hand, is identified as harmful.

However, the bottled Kansui now being marketed worldwide is a solution. On its label you will find “Potassium Carbonate & Sodium Bicarbonate Solution”. This means that sodium carbonate and potassium carbonate are used in precise percentages that are diluted in water to create a safe solution for preparing noodles and even other dishes such as Chinese moon cakes. Kansui for Ramen on the market have the proportion of 80% sodium carbonate and 20% potassium carbonate.

Noodles containing Kansui have been prepared this way for thousands of years, and this solution is still used, so there is no doubt that it is safe. But since potassium carbonate is a potentially dangerous substance that is best not handled or ingested, I will explain later in the article how to replace it with a simple dietary supplement.

Methods of Preparation

I really spent a long time, more or less 4 years, to find a way to replace this ingredient. The answer came through Harold McGee’s article, an article more than 10 years old. You can’t imagine the joy, not only had I found the solution, but he was explaining how to make alkaline water!

In short, the article said to bake some Sodium Bicarbonate, what we all have well or poorly in our pantry, in the oven for 1 hour at 120 °C. Simple, right? This process will go to transform the pH of Sodium Bicarbonate, making it more acidic and turning it into an alkaline salt, namely Sodium Carbonate. Once obtained you have to let it cool down and most importantly you must not touch it, not your bare hands! Its pH is not compatible with that of the skin, so it could create irritation. At this point after finally preparing my Kansui I prepared the noodles.

The Result. A firm, elastic paste that did not absorb the broth and became mushy, compared to previous attempts it was fine but not great… There was a more or less slight taste of sulphur, which did not make the dish totally enjoyable. After further research, I came across a series of articles on Serious eats. The most enlightening was Sho Spaeth’s article in which starting from McGee’s procedure, he creates a more precise and, above all, univocal method for any amount of Bicarbonate that you want to turn into Sodium Carbonate.

How to make alkaline water
How to make alkaline water

How to Make Alkaline Water

OK, I guess it’s time to get down to business and figure out how to prepare the ingredient needed to make our alkaline noodles. First, the oven temperature must be 175 °C (347 °F). The second important point is that the amount (whatever it is) of Sodium Bicarbonate will have to be reduced by 2/3 of its weight.

That is, “x g of B.S. : 3 × 2 = G of Kansui”. EG. 250 g of B.S. should become 166 -167 g (250 : 3 × 2). The final number is of course approximate, whether it will be 163 g or 169 g is fine though!

This is the unique formula, but let’s see how to proceed, I used 100 g of B.S. so I will base myself on that.

  1. Preheat the oven to 175 °C;
  2. Line a baking tin with foil and weigh it. Note the weight so you don’t forget, in my case I used a shallow cake tin, once lined it weighed 166 g;
  3. Weighing sodium bicarbonate, I used 100 g, so 100 : 3 x 2 = 66 – 67 g of final product;
  4. Once the oven is hot, put the baking tray in the oven and set the timer to 30 minutes;
  5. After the 30 minutes have expired, weigh the pan as is, take the current weight and subtract the weight of the lined pan. This way you will know the current weight of the B.S. (in my case it was 74 g). Stir with a spoon and reinforce for another 30 minutes;
  6. After 30 minutes, repeat the previous operation, weigh the baking tin and subtract the weight of the lined baking tin. Based on the quantity I used (100 g), I obtained 63 g of Kansui with this second baking;
  7. Let it cool and then store the alkaline powder in an airtight jar. It has no expiry date.

As you can see, the process is not at all complex. One thing must be taken into account though. The more bicarbonate you want to turn into Kansui, the longer the cooking time will be, so you will have to adjust the cooking time according to the results of the various weighing.

Kansui noodles
Kansui noodles

To Complete the Kansui Blend

The Sodium Carbonate is ready, but to make the Kansui we prepare at home complete, it would be missing the Potassium Carbonate, but as mentioned above this is a NOT safe component that we are going to replace with Potassium Bicarbonate. You will only need to buy it on the internet or in a pharmacy since it is a dietary supplement. Sodium Carbonate gives the paste a chewier texture, while Potassium Bicarbonate gives a firm, taut consistency.

The Blending

To mix them, simply mix the desired quantities at the time of preparation. Always dissolve the salts one at a time, if you mix them all together their combined composition will make dissolving the grains longer and more difficult. Personally, I dissolve the salt first, then the Potassium Bicarbonate and finally the Sodium Carbonate. The quantities of one and the other can vary depending on the recipe, here on the blog you will find the doses for both, including how they interact in the dough, also feel free to experiment!

Of course, after preparing the Alkaline Water Kansui, I prepared the Ramen. The annoying sulphur taste disappeared; the texture much improved, not perfect…. As I said the Kansui was the first hurdle to get the Ramen Noodles, the most complex I dare say, now we can move on to the Ingredients for the Ramen Noodles.

5 from 1 vote

Alkaline Water Kansui Preparation

Method for preparing Kansui powder, a key ingredient in the preparation of ramen noodles Noodle.
Porzioni 1 jar
Tempo di Preparazione 30 minutes
Tempo di Cottura 1 hour
Tempo totale 1 hour 30 minutes


  • Cake Pan 24 cm Ø with low borders or larger depending


  • Tin Foil
  • Jar
  • Scales


  • 100 g Sodium Bicarbonate

To Complete the Blend

  • to taste Potassium Bicarbonate (Kansui)


  • Heat the oven to 175 °C.
  • Line a baking tray with foil and weigh it. Note the weight so you don't forget it.
  • Weight of sodium bicarbonate, so: 100 g of bicarbonate : 3 × 2 = 66/67 g of final product.
  • Once the oven is hot, put the baking tray in the oven and set the timer to 30 minutes.
  • After 30 minutes, weigh the baking tin as is, take the actual weight and subtract the weight of the lined baking tin. In this way you will know the current weight of the B.S. i.e. 74 g. Stir with a spoon and reinforce for another 30 minutes;
  • After 30 minutes, repeat the previous operation, weigh the baking tin and subtract the weight of the lined baking tray. Based on the 100 g used, with this second baking, you will have obtained 63 g of Kansui.
  • Let it cool down and then place the alkaline powder in an airtight jar. It has no expiry date.



  • The more bicarbonate you want to turn into Kansui, the longer the cooking time will be, and therefore you will have to adjust the baking according to the results of the various weights.
  • Unique formula for preparing any amount of Kansui: X g of B.S. : 3 × 2 = G of Kansui
  • If you prepare large quantities, use a wider baking tray so that the baking soda forms a bed not too thick, maximum 1 cm thick for optimal preparation.
Chef: Taira by R.J.
Calorie: 1kcal
Course: Basic Preparation
Cuisine: Chinese, Japanese
Keyword: Fresh Noodles
Difficoltà: Easy
Temperatura: 175 °C/347 °F


Serving: 63g | Calories: 1kcal | Carbohydrates: 0g | Protein: 0g | Fat: 0g | Sugar: 0g

Le informazioni nutrizionali mostrate sono una stima fornita da un calcolatore nutrizionale online. Non deve essere considerato un sostituto del consiglio di un nutrizionista professionista.

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Article updated on 28/11/2023

Main Sources: Yamamoto Noodles, article: Ramen noodle ingredients – kansui, etc.

Join the Conversation

  1. Jamie Oliver made kansui in “Jamie and Jimmy’s Friday Night Feasth with Josh Hartnett”.

    1. Really? Thanks for the information, I’m going to look for it, I hope to find it on YT!

  2. Clay G says:

    You wrote “This process will transform the pH of the sodium bicarbonate, making it more acidic…”

    Should say “basic” as you are trying to increase alkalinity.

    1. thanks for the tip ?

  3. en caso de no contar con carbonato de potasio con que puedo reemplazarlo para acercarme a un fideo ramen

    1. Puede reemplazar con la misma cantidad de carbonato de sodio. Antes de descubrir esta combinación, solo usaba carbonato de sodio y seguían siendo buenos!Espero haber traducido bien 😅

  4. in case of not having potassium carbonate with which I can replace it to approach a ramen noodle

    1. You can replace with the same amount of sodium carbonate. Before discovering this combination, I was only using sodium carbonate and they were still good!

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