Low phytate lupin flour based biomass obtained by fermentation with a mutant of Aspergillus niger

A group of 10 morphological mutants of Aspergillus niger was tested for synthesis of phytase. Strain 11T25A5 was selected for phytase production in solid state fermentation (SSF) in the presence of phytic acid (PA). The production of phytase in the medium was accompanied by degradation of phytic acid. Phytase activity increased from 28 to 72% when lupin flour was used in the fermentation mixture. The residual content of phytic acid in the fermented material depends on both the proportion of lupin flour in the mixture and the particle size of the flour. Coarse lupin flour produced fermented material with a lower level of residual phytic acid. The fermentation of lupin flour with A. niger strain 11T2545 may be used to obtain a low phytate biomass with potential for use as an ingredient for feed or food production.