The solid state of L-alpha-alanine is routinely used as a dosimeter for X-ray, gamma, and electron radiations. Recently, in the framework of boron neutron capture therapy, it has been suggested that L-alpha-alanine can be used to characterise the neutron dose as well. While Monte Carlo simulations are optimised to reproduce as accurately as possible the neutron radiation source, the description of the alanine molecule is still based on rough approximations. We propose a neutron transmission experiment to measure the actual neutron cross section of L-alpha-alanine and a series of other simple amino acids for dosimetry applications. Such a library of experimental neutron cross sections can provide a realistic neutronic response of human tissues, of particular interest in the framework of boron neutron capture therapy.