It is a nutritious meal and could have been part of the feasts. It is also possible that it has replaced Haoma. Haoma is a scared herbal mix known for its healing properties. It was a major cult on its own with many rituals and ceremonies. The cult is still performed by the Zoroastrians today, but is abandoned by the rest of the Iranians.
Coins symbolizing wealth and prosperity, fruits and special meals are present as well.
There have been major attempts by the Muslim rulers over the centuries to minimize it, ban it or get rid of it once and for all. The reasons for their failure should be sought in the spirit of this festival. Contrary to the Islamic traditions where death and martyrdom mark all the major rituals, No Ruz is a celebration of life. Forces of nature completely beyond them dominated people in ancient times. They formed a union with these forces to protect themselves.