Study of the Effect of Phycocyanin Pigment on Physicochemical, Sensory, Microbial and Antioxidant Properties of Cheese

Due to its unique role, phycocyanin pigment extracted from the cyanobacterium Spirulina platensis can play an important role in enriching traditional cheeses. In this study, the amount of protein, fat, ash, moisture, β-carotene and pH of fortified cheese with different concentrations of phycocyanin pigment were determined. In addition, the counting of bacteria was done along with the assessment of antioxidant properties. Also, gas chromatography-mass spectrometer GC-MS test was performed to identify volatile compounds during 1, 3, 7, 14 and 21 days. The results of tests showed that the amount of fat, moisture, pH and 1,1-diphenyl-2-picrylhydrazyl (DPPH) of fortified cheeses has decreased significantly compared to the control. Also, the amount of protein, β-carotene, ferric reducing assay power (FRAP) and nitric oxide trapping increased significantly compared to the control. Sensory evaluation had also significant increase in satisfaction, except for the sense of smell compared to the control. In addition, no signs of Escherichia coli and Staphylococcus aureus were found during different days. However, the presence of coliform bacteria was evident from 7 to 21 days in enriched and control cheeses. Also, the results of volatile compounds obtained from GC-MS test in control cheese and enriched cheese with 1% phycocyanin pigment show the presence of compounds with antimicrobial properties that played an important role in the shelf life and quality of cheese. It is hoped that the results of this study will be the basis for empowering the food industry in using pigments obtained from cyanobacteria.