Royal Jelly ("a glandular secretion and its color is a whitish yellow. Its consistency is creamier and less viscous than honey. Its taste is bitter, although not offensively so.") according to this OU article has different opinions as to it's Kosher status.
Some have argued that royal jelly should be permitted because it is honey-like, and presumably included in the Scriptural exception as well. But this argument is difficult to support, based on the two reasons cited by the Gemara above. First of all, royal jelly is a glandular secretion, and therefore subject to the general rule of that which comes from an impure (being) is also impure. Also, since it differs in appearance, taste, and function from honey, it should not be included in the Scriptural exception granted to bees’ honey since royal jelly can be considered a totally different food than honey.
Others have contended that royal jelly is not considered fit for human consumption as it is “very bitter” and therefore not subject to any prohibition. This contention, however, is erroneous, for while royal jelly is indeed somewhat tart and bitter, it is by no means inedible even in its pure raw state. This was confirmed by our gentile tester.
Similarly, this Yeshiva.org.il article says:
There are different approaches in Halacha on this matter. Some hold it to be like honey since the Talmud does not differentiate between the two; Others hold it to be non Kosher because of your point as it comes from an insect. Some are lenient in the case of royal jelly when it’s mixed with honey. (See Talmudic Encyclopedia 23 p. 356 and footnotes for the different sources)
Who are the opinions that hold this? (I don't have access to an Encyclopedia Talmudis right now).
So that is four opinions I'm trying to track down.
- Royal Jelly is like honey and Kosher for the same reason.
- Royal Jelly is not fit for human consumption.
- Royal Jelly mixed with honey doesn't forbid keilim or is permitted outright.
- Royal Jelly mixed with honey does forbid keilim or is forbidden outright.