It seems that AES is non homomorphic. I am seeking a public key non homomorphic encryption that has been proved to be such or at least is accepted as non homomorphic. The internet search leads to those that are homomorphic. Any lead?
RSA with proper padding
So, use RSA (or actually any trap door one way function) with proper padding. For instance: OAEP padding. These are designed to achieve indistinguishability, which has also been mentioned in the comments. The padding which uses a hash internally kills all homomorphic properties of the cipher.