[3] The periodic acid-Schiff method and Sudan black B dye was used to help determine that Vitellin is a glycolipoprotein because it stained positive when tested.
This phosphoprotein acts as a membrane, 1-3.5μm, that encloses the egg that comprises at least five glycoproteins that resemble the zona pellucida evident in mammalian organisms.
Vitellin comprises a vast fraction of the proteins found in eggs, and due to this, they are easily characterized with biochemical methods in order to elucidate molecular, developments, and physiological regulation studies.
Vitellin was studied in honey bees and was found that it contributed to the health of the embryo in the form of immunity in the embryonic stages.
Annual review of entomology 24.1 (1979): 475-505. https://doi.org/10.1146/annurev.en.24.010179.002355 Zhu, Jiang, Leslie S. Indrasith, and Okitsugu Yamashita.