Value Village ／ Food & living
This answer is a draft. It stays unpublished until legal review and source verification are complete.
Electric kettles have spread rapidly through Japanese homes and, alongside the traditional electric hot-water pot (電気ポット, denki potto — a large insulated dispenser that keeps water hot all day), they are the main way of boiling water. Here we look at the belief that "it only holds water, so it cannot get dirty", at the white crystals (limescale) that build up, and at scald accidents.
| Part | Frequency | Method |
|---|---|---|
| Scale inside (white crystals) | Monthly (every 2 weeks in hard-water areas or with heavy use) | Dissolve 1 tablespoon (about 15 g) of citric acid (クエン酸, kuen-san, sold at drugstores and 100-yen shops) in 1 L of water, boil, leave for 1–2 hours, empty and rinse. If the maker offers a "citric acid cleaning" mode or its own cleaning product, follow that |
| Spout and filter | Monthly | Remove and wash. Scale comes off with a cotton bud or toothbrush |
| Outside, lid, handle | Weekly | Wipe. Never pour water over the electrical base |
| After use | Every time | Pour away leftover water and leave the lid open to dry (prevents slime and smells) |
| Electric hot-water pot (keep-warm type) | Citric acid monthly; change the water every day (water kept hot for long periods can grow bacteria) | — |
[Verify] Check the quantity and method for citric acid against the manual for your product, and the accident cases against Consumer Affairs Agency and NITE material.
Scale builds up over a matter of months, efficiency drops and flakes come off. Citric acid once a month.
They are minerals such as calcium and are not harmful. They dissolve in citric acid.
Scale is removed with an acid (citric acid). Baking soda is an alkali and does not work on scale (see the article on baking soda and citric acid).
The most common accident is a child scalded by a kettle tipping over. Choose a spill-proof design, keep the cord out of reach and stay away from the edge of the table.
It costs ¥10–20 a day in electricity. A vacuum-insulated pot, or boiling only what you need, is cheaper. Change water that has been kept hot every day.
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https://www.caa.go.jp/policies/policy/consumer_safety/child/
https://www.nite.go.jp/jiko/chuikanki/
https://www.aeha.or.jp/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
Some ingredients need thorough cooking. Eat raw only foods that are sold for raw consumption. If you have allergies, check the ingredients.
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