An ecological nixtamalisation process (EP) for making whole corn flour for tortillas was compared with the traditional nixtamalisation process (TP). One of the problems of TP is high level of solid losses. The aim was to evaluate the composition of these losses. In EP, dry matter losses of nejayote were from 1.2% to 1.4%, while in TP 3.2%. Nejayote from TP showed a pH of 11.9, whereas EP showed a pH close to neutral. The pericarp was retained in EP with the use of calcium salts, whereas in TP lime destroyed it almost completely. Losses of total dietary fibre in nejayote solids were about 41.2% for TP compared to an average of 17.4% for EP. Most of nejayote losses in TP were soluble fibre (30.4%), compared with EP that ranged from 6.2% to 7.9%. All compounds retained by nixtamal from EP are important sources of nutrients and dietary fibre.