I think the prey may be a Lacewing but delighted with any correction.
Read an article today about a very recent study on the discovery of at least 8 new Lacewing types in the UAE; that is why I'm particularly interested in the prey of this bird. If anybody wants other views of the insect then they can be provided.
The study referred to above can be found here: https://www.researchgate.net/publication/315495434_Dobosz_R_Abraham_L_and_Roberts_H_2017_Interesting_Lacewings_Neuroptera_Berothidae_Nemopteridae_Myrmeleontidae_from_the_United_Arab_Emirates_Acta_Entomologica_Silesiana_25_1-8
The image below is just before the insect disappears down the throat. In a previous image of a Bee Eater I asked if tossing the prey in the air before swallowing was common - another image in this series showed the insect being tossed just before being swallowed.