This work was established for using potato chips manufacturing wastes as a substrate for
the production of food colorant pigments by Monascus ruber Went AUMC 5705, then it was
utilized individually for coloring some food products (drops sweets). The effects of different
environmental and nutritional factors were studied in solid state fermentation (SSF). The
maximum concentrations of red, orange, and yellow pigments produced by M. ruber were
147.3, 179.6 and 221.7 U/g of dry fermented materials, respectively. The optimum conditions
for pigments production were determined to be 50%, 6.5, 3 % and 15 days, for the initial
moisture content, pH, (NH4)2SO4 , and incubation period, respectively. Moreover, the optimum
inoculum size, particle size of potato chips and fermentation temperature, were determined to
be 81×104 spores/10g dry substrate, 1.5 mm and 30 °C under dark condition, respectively.
Then, the pigments mixture was separated into red, orange and yellow water insoluble pigments
that used as coloring agents of drops sweets flavoured with fruits odours. This study revealed
that potato chips wastes are an innovative raw material for pigments production by M. ruber in
SSF.