Do this extra step if you are using non pasteurised egg
Crack the egg into a container and leave it in 140°-160°F ( 60-70°C) hot water bath for 5 minutes.
Separate the egg to egg yolk and white. *4
Combine all ingredients except oil in a small mixing bowl. *5
Transfer the egg yolk and other ingredients mixture into a electric blender.
Add a small amount of oil at a time and blitz or pulse the blender.
Repeat this step until all the oil is added and egg mixture and oil has emulsified creamy.
Transfer the Japanese mayo into a sterilized container. *6
*1 Use pasteurised egg if possible. I used a large egg's egg yolk which weighs about 0.5oz (13g)*2 If you don't have or access to rice vinegar, you can substitute apple cider vinegar.*3 I used rice bran oil. You can use any of vegetable oil that does not have any distinctive flavour.*4 I used the leftover egg white for making scrambled egg or Tamagoyaki (Japanese rolled egg omelette). *5 You can place them straight into the blender but I found it splashed everywhere and does not combine the ingredients well. *6 Try to use it within the day you made or next couple of days. Mayonnaise can not be kept in the freezer. Sterilise the container by adding boiling water to it initially.*7 Make sure you use about 10% vinegar to the total amount of mayonnaise you are making. *8 This recipe makes about 9oz (250g)