• HOME >
  • Teapot and Tea Equipment

The taste of water differs depending on how tetsubin is made

[2013.08.29] Posted By

Nanbu Cast Iron Kettle
Many people are aware that a tetsubin effects the taste of water by making it smoother. But, do you know that different brands or different manufacturing method affects the taste remarkably too? I’ve carried out the following experiment to verify the effects of the taste between the different manufacturing processes.

Kamayaki process that affects the performance of a tetsubin

Tetsubin is a cast iron kettle where melted iron is poured into a mold which carries a distinctive design created by the manufacturer. After the casting, the tetsubin is in white-silver color and the tetsubin in this condition gets rusty easily. Thus, the tetsubin is then baked with charcoal fire. This process is called “Kamayaki” which means “firing in a pot”. The term pot refers to a small open kiln. The objective of Kamayaki is to reduce the surface of tetsubin which would prevent it from rusting. The charcoal fire is an unsaturated fire; when the surface of tetsubin is reduced, it will turn into a dark blue color. This process affects the taste a lot. I have requested the tetsubin manufacturer to produce a tetsubin according to my parameter and study the relationship with the taste of water.

Tetsubin before Kamayaki

Tetsubin Before Kamayaki

Tetsubin After Kamayaki

Tetsubin After Kamayaki

  1. Tetsubin without Kamayaki
  2. Tetsubin with twice as long Kamayaki as standard

I have compared the taste of water boiled in the above tetsubin versus a normal tetsubin. We used hard charcoal for the experiment.

The results are as follow:

  1. The tetsubin without Kamayaki noticeably increases body and after taste. The performance of this model in terms of the water taste was the best among 3 tetsubins.
  2. The tetsubin baked twice as long as ordinary tetsubin does not make the taste of water smooth at all. The intensity of the after taste was more or less the same as stainless steel kettle. However, the body was weaker than that of stainless steel electric kettle.
  3. Kamayaki reduced the body of water regardless of the processing time

Non-Kamayaki produces the best result in terms of the taste

Based on the above experiment, I am affirm that the Kamayaki process affects the performance of a tetsubin. Ironically, the non-Kamayaki tetsubin produces strongest body and after taste, however, there is a downside as it is so easy to get rusty, so fast that it started rusting while I was using it. Since it gets rusty no matter how we use it, it is somehow not practical.

The Kamayaki may affect the surface structure of tetsubin

We found that the longer the Kamayaki is carried out, the lower the performance of tetsubin will be. I assume that it has something to do with the surface structure of tetsubin. Moreover, the inverse proportion between firing temperature and the performance was also observed using clay teapot. The higher firing temperature melts down the mineral granule and decreases the surface area. A tetsubin has more a complex and larger surface area as compared to the normal iron. Using the same theory, I would assume the reason for the decrease in performance after undergoing longer firing or higher baking temperature would be due to the melt-down of the particles and also, resulting in a decrease in surface area of tetsubin.

The type of charcoal used for Kamayaki affects the taste

Based on my investigation, I noticed that different brands of tetsubin use different types of charcoal where some would use hard charcoal and some soft charcoal. The firing temperature of hard charcoal is higher. If we just judge based on the taste, it would be more ideal to use soft charcoal.

Satetsu Tetsubin

Have you heard of “satetsu tetsubin”? Satetsu means sand-iron in English. Although the material used for satetsu tetsubin is not the same among the different manufacturers, the essential point is a satetsu tetsubin does not undergo the Kamayaki process. Originally, satetsu iron has higher density where it is said that the rust is unable to penetrate into the iron structure. Therefore, the satetsu tetsubin produces a very strong body and after taste. Long ago, I used to think that the satetsu tetsubin performed great due to its material. But for now, I believe that the main reason for a satetsu tetsubin to perform well is because there was no Kamayaki process performed. However, the satetsu material is very brittle. It may crack with a small mistake in handling which normal cast iron kettle would not.

satetsu tetsubin

satetsu tetsubin 0.9L

Related Articles

How to get the latest update on HOJO Tea?

1. Follow Twitter, 2. Click "Like" on Facebook, and 3. Subscribe in newsletter. You can have the latest tea news from HOJO Tea.

Subscribe the Newsletter to enjoy the privileges
You may receive a free sample upon purchase, or you may have the priority to purchase special products. So please remember to subscribe our newsletter as well as the social network.
HOJO TEA Malaysia online Shop

HOJO TEA Online Shop NEWSlist

Discover the long-lasting flavor profile of 2023 Shi Feng Long Jing
We have launched the 2023 harvest of Shi Feng Long Jing tea. Shi Feng Long Jing tea, also known as Shi Feng Dragon Well tea. It is one of the most famous and highly regarded teas in China.Shi Feng Long Jing tea is characterized by its flat, spear-shaped leaves that have a vibrant green colour. …
Rare Jasmine Tea Uniquely Crafted from Ripe Pu-erh
Instead of sourcing finished jasmine tea, we specialize in producing custom-made jasmine tea by bringing our carefully selected raw materials to jasmine factories. Over the years, we have created numerous unique jasmine tea varieties that are not available elsewhere, such as Pu-erh jasmine tea made from raw Pu-erh tea leaves, Jasmine Silver Needle made from …

NEW ARTICLES

Discover the long-lasting flavor profile of 2023 Shi Feng Long Jing
We have launched the 2023 harvest of Shi Feng Long Jing tea. Shi Feng Long Jing tea, also known as Shi Feng Dragon Well tea. It is one of the most famous and highly regarded teas in China.Shi Feng Long Jing tea is characterized by its flat, spear-shaped leaves that have a vibrant green colour. …
Rare Jasmine Tea Uniquely Crafted from Ripe Pu-erh
Instead of sourcing finished jasmine tea, we specialize in producing custom-made jasmine tea by bringing our carefully selected raw materials to jasmine factories. Over the years, we have created numerous unique jasmine tea varieties that are not available elsewhere, such as Pu-erh jasmine tea made from raw Pu-erh tea leaves, Jasmine Silver Needle made from …
Introducing 3 Varieties of Phoenix Dancong Oolong Tea
We have released new types of Phoenix Dan Cong Oolong Tea that are finished with more rounds of roasting with traditional charcoal fire by skilled tea master. In Phoenix, the locals called it Nong Xiang style, meaning that tea is giving more intense matured flavor. Nong Xiang tea refers to tea that has been roasted …
Exploring the Taste Diversity Within a Tea Tree: Apical Buds vs. Lateral Buds
Do you believe that all tea leaves have the same taste as long as they come from the same tree? I would like to explain that the taste of tea can vary significantly depending on the plucking position, even when harvested from the same tree. The Difference in Flavor Due to Different Harvesting Parts of …
Hidden Costs of High Valuations of Old Tea Trees
Over the past decade, tea enthusiasts in China have been captivated by teas harvested from Ancient Tea trees, particularly those from Yunnan province, Phoenix Dan Cong Oolong Tea and Wuyi Rock Tea. However, as Ancient Tea trees are rare, the prices of teas harvested from them have skyrocketed. As a result, some farmers who possess …
Discover the Unique Taste of Wu Jia Ping Zhang Ancient Tree Raw Pu-Erh Tea
We have released Wu Jia Ping Zhang ancient tree raw pu-erh tea for 2020 and 2021. This tea is grown in tea gardens located around 2100 meters above sea level in the southwestern part of Lincang City, Yunnan Province of China, just a few dozen kilometres from the Myanmar border. Single-origin tea Wu Jia Ping …
Introducing 3 High Grown Darjeeling First Flush Teas Produced Using Sustainable Methods
We have released three types of Darjeeling First Flush, all of which are grown sustainably. The tea gardens are maintained using natural farming methods, and the use of fertilizers is limited when growing the tea trees. As a result, the tea gardens closely resemble their natural state. Unlike common Darjeeling tea, these teas grow slowly, …
New Release of Tsuge Zairai Sencha from Sustainable Tea Garden
Tsuge Zairai Sencha 都祁在来煎茶 is made from “zairai” tea plucked in spring, from the naturally farmed tea garden located in Tsuge, Nara City, Nara Prefecture. The tea garden of Tsuge Zairai Sencha is maintained in sustainable manner applying neither pesticide nor fertilizer. Tsuge Zairai Sencha has a subtle and refreshing floral scent with a hint …
New Release of Da Xue Shan Wild White Tea Cake 2021
Da Xue Shan Wild White Tea 2021 is available now. This tea is always very popular in our shop. In Japan, we brought in loose tea this year, and for Malaysia we produced 200g cake. Mao cha before compressing into cake Very limited resources This tea is made from the wild tea, called Camelia taliensis. …
New Release of 2 Types of Darjeeling 1st Flush
We have released two types of Darjeeling 1st Flush Tea. The reason why the Darjeeling 1st Flush is greenish In Darjeeling tea, the 1st flush refers to the first-plucked spring tea. Usually, the Darjeeling 1st Flush tea is greenish. From the outlook, it looks like a green tea. Many people misunderstand that it is green …

PAGETOP