Daikon oroshi is grated raw daikon, which is Japanese radish, used for Japanese dishes as a condiment. The spiciness of daikon oroshi can reduce the fishery smell, so it is often added on cooked fish such as grilled pacific saury. It goes well with dishes such as tempura and meat which are greasy, because it gives a fresh taste and can help to digest the food.
Daikon contains digestive enzyme, but when it is heated, the enzyme will not be effective. So eating daikon oroshi is a good way to take in the enzyme to help the digestion. Daiko oroshi also contains vitamin C, which is obviously good for your health. There is a saying in Japanese that you will not need a doctor if you eat daikon oroshi.
The sweetness is richer than the spiciness when you eat raw daikon, but daikon oroshi has a slight spicy taste. This is because the spicy component does not exist in raw daikon. However, when daikon is grated, the cellular tissues will be destroyed and the chemical reaction creates the spicy component.
After 5 minutes grating daikon, the spiciness reaches its peak, and after that it will gradually lose its spiciness. If you want to make a sweeter daikon oroshi, the part of the daikon near to the leaf should be used. The way to grate the daikon is to slowly grate into circles and along the fiber, so that the cellular tissues will not be destroyed.
Putting daikon oroshi on a pot of meat and vegetables is called mizore-nabe, which mizore means sleet, because daikon oroshi looks like sleet. To make a Japanese style hamburger stake, daikon oroshi is put on the top of the hamburger stake and soy sauce based sauce is poured.