Background: Today, there is an increasing concern about the consumption of synthetic colorants in food because of their possible health hazards. Monascus purpureus have attracted a great deal of attention as they produce various colored pigments with high chemical stability but they produces citrinin, a secondary toxic metabolite, along with the pigments. This study aims to investigate the amount of pigment and citrinin reduction by different treatments of Saccharomyces cerevisiae such as heat treatment and suspension concentration. Result: the results of this study indicated that the ability of Saccharomyces cerevisiae regarding citrinin adsorption increased with elevation of temperature and yeast concentration. The maximum extent of citrinin adsorption was related to the heat treatment at 121 oC and 105 cell ml-1 yeast concentration, which citrinin reduced from 4.43 mg L-1 in control to 0.1 mg L-1. Heat treatment of 103 cell ml-1 suspension of S. cerevisiae cells at 50 oC, with 0.56 mg L-1 citrinin remaining in the medium, showed the lowest ability for citrinin binding. The optimum absorbance of all red, orange, and yellow pigments was observed in the heat treatment at 50 °C and 103 and 104 cell ml-1 yeast concentration which was greater than the control. Conclusion: We can conclude from this study that the heat treatment of S. cerevisiae can be a useful way to reduce citrinin to below the standard limits.

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