Value Village ／ Food & living
This answer is a draft. It stays unpublished until legal review and source verification are complete.
This looks like a question about kitchen efficiency, but it is also one about hygiene. The order itself is written into the Ministry of Health, Labour and Welfare's food-poisoning prevention points. In a small Japanese kitchen, often with one chopping board, the order matters all the more.
The preparation section of the Ministry of Health, Labour and Welfare's "Six Points for Preventing Food Poisoning at Home" says: do not cut vegetables or fruit to be eaten raw with a knife or board that has cut raw meat or fish, and wash the tools straight after use and pour boiling water over them. Of the three principles of food-poisoning prevention — "don't pass it on, don't let it multiply, kill it" (つけない・増やさない・やっつける) — preparation is the step that covers "don't pass it on".
1. Wash your hands 2. Vegetables and fruit to be eaten raw 3. Vegetables to be cooked 4. Raw meat and fish (last) 5. Wash the tools you used, and your hands
[Verify] Check against the original Ministry of Health, Labour and Welfare leaflet.
It is for hygiene. Do not cut raw vegetables with tools that have just handled raw meat or fish.
You can use it once washed, but keeping to the order is the surer way. Use separate boards if you can.
Some ingredients dry out or discolour from the cut surface. Some are better cut just before use.
The right time depends on the ingredient and the seasoning. Longer is not automatically better.
Public advice calls for washing your hands each time you change ingredient.
---
https://www.mhlw.go.jp/topics/bukyoku/iyaku/syoku-anzen/dl/pamph01_05.pdf
https://www.gov-online.go.jp/article/20110602/entry-8196.html
https://www.n-shokuei.jp/eisei/sfs_6point.html
⚠️ 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.
Take great care when handling knives.
Tell us if this has changed
Approved contributions keep the contributor's name, shown in five languages.
Other languages：日本語 ／ 简体中文 ／ 繁體中文 ／ 한국어
Value Village is not a government body. Always confirm procedures on the official site.
Written by Value Village from public sources. Nothing here is reproduced from another site.