Why does blending blueberries, milk, banana and vanilla extract cause the mixture to have a yogurty consistency? A cup of milk
A cup of blueberries
A banana
Three shakes of vanilla extract liquid


The original plan was to have a milkshake, but the result is quite a nice desert! Like a no cook yogurt.

Looking more closely, the milk has curdled, but not like when mixing it with orange juice. Sort of reminds me of the cheese making process too
The pectin from the blueberries jelled in the presence of the calcium in the milk. The texture might be unexpected, but it is perfectly safe and tasty. It is the same process that thickens blueberry jam. 

It shouldn't be curdled, that is the clumping of milk proteins in the presence of acid. Here, the milk proteins stay suspended in the milk as usual, it is the pectin that builds the "mesh" of the creamy consistency.