The color of the royal jelly is of great importance because it is an indicator of its freshness and suitability. The fresh royal jelly has a bright white color. But when it comes in contact with the air or exposed to light, its color changes to yellow and dark gray.
The systematic way of producing royal jelly is by the method of vaccination. In this method, in royal cells, we vaccinate larvae of 1-3-day-old workers, and these vaccinated royal cells are placed in honeycombs, which do not have a queen.
On the third day of vaccination, the vaccinated royal cells have the largest amount of royal jelly. After that we remove the queen’s larva, we collect the royal jelly and then we can repeat the process of vaccination in the same royal cells.