What causes egg-covered puffed rice cakes to become soft when pan fried (and how to control it)?

While recently making fried bread slices dipped in egg (both white and yolk), I've run out of bread. Since I've already had everything else prepared, I've decided to go ahead and replace the bread with (Wester-style) puffed rice cakes.

Anticipating the result would be not very palatable, I was instead surprised that the crispy and brittle (even after a long dip in the eggs) rice cakes became soft and mostly chewy during frying - turning out to be quite s viable substitute for this type of snack.

Interestingly, I've later tried to reproduce this process of softening up with just temperature and temperature and cooking oil, without success, implying that the egg dip has to be a factor in the transformation.

My question is: what in the combination of eggs and pan frying causes the softening of the puffed rice cakes, and what are the influencing factors in the context of controlling this process?

For completeness sake, some additional information:

• the egg dip used was completely unseasoned, just egg white and yolk briefly stirred together with a fork,


• the rice cakes were composed of puffed "pure grain brown rice" and 0.9% of "sea" salt (hence no seasoning in the eggs),


• the cakes were submerged in the eggs for up to a minute (without losing rigidity),


• they were pan fried on a teflon pan in a small amount of rapeseed oil, near its smoking point, for about the same time you would fry bread.