A stochastic description of a racemic mixture is developed taking into account the slight energy difference between enantiomers originating from parity violation (Delta E-PV approximate to 10(-13) Jmol(-1)). The system can be described by an asymmetric binomial distribution. A method is developed to calculate the probability of forming the more-stable isomer in excess, which is not significantly larger than 50% under normal conditions. It is concluded that the parity-violating energy difference between enantiomers is very unlikely to be relevant in considerations about the origin of biological chirality.