Wiktionary
yellow 2g
n. (context chemistry English) A yellow azo dye used as a food colouring.
Wikipedia
Yellow 2G
Yellow 2G is a food coloring denoted by E number E107. It has the appearance of a yellow powder, and it is soluble in water. It is a synthetic yellow azo dye.
It appears to cause allergic or intolerant reactions, particularly amongst those with an aspirin intolerance and asthma sufferers. It is one of the colors that the Hyperactive Children's Support Group recommends be eliminated from the diet of children.
It is not listed by the UK's Food Standards Agency among EU approved food additives. Its use is also banned in Austria, Japan, Norway, Sweden, Switzerland and the United States.