Study On Solid Fermentation Process And Application Characteristics Of High Yield Monascus Pigment

As an important microbial resource in China,monacorin K,amma-aminobutyric acid(GABA)and other secondary metabolites can be produced by Monascus.Among them,monascus pigment is a kind of high-quality natural edible pigment,which is widely used in meat products,condiments,flour products,wine industry and other food industry.Monascus pigment also has antioxidant,anti-tumor,anti-bacterial,anti-inflammatory,lower blood glucose levels and other characteristics,has health value and broad application prospects.Further research on screening high-yielding strains,optimizing fermentation technology and exploring its application characteristics are the basis of raising the color price of monascus pigment and promoting the product development of monascus pigment.Therefore,this paper firstly screened and identified strains of high-yielding monascus pigment,optimized the solid-state fermentation process on this basis,and studied the key application characteristics such as antioxidant,bacteriostatic and stability.The main research results and conclusions are as follows:(1)Screening and identification of strains with high yield monascus pigmentRice was used as raw material for fermentation,and six strains of preserved Monascus were used as test strains for solid fermentation.The color value of monascus pigment was used as the index to screen high-yielding strains,and the colony morphology,microscopic individual morphology and molecular biology identification of the target strains were observed.The results showed that the RF production capacity of monascus pigment was strong,and the morphological observation and ITS sequence analysis showed that it was Monascus ruber.(2)Optimization of solid-state fermentation process for high yield monascus pigmentRice was used as fermentation raw material,and Monascus RF was used as solid state test strain.The color value of different soaking acid species,initial pH value,initial moisture content,inoculation amount and fermentation time were determined by single factor test.On this basis,the fermentation process parameters were optimized by orthogonal test.The results showed that soaked with acetic acid,initial pH value 4.5,initial moisture content 45%,inoculum 4%,fermentation time 13 days,monascus pigment red price is 5780 u/g,yellow price is 4891 u/g.(3)Application characteristics of high yield monascus pigmentMonascus RF solid fermentation pigment was used as material,the antioxidation,bacteriostatic and stable properties of the product were studied.The results showed that monascus pigment had DPPH radical scavenging ability,ABTS radical scavenging ability and reducing ability.Monascus pigment has strong bacteriostasis against E.coli,certain bacteriostasis against bacillus subtilis and yeast,weak bacteriostasis against staphylococcus aureus and lactobacillus,but no bacteriostasis against salmonella.Monascus pigment has good thermal stability,and the storage rate of red pigment and yellow pigment is more than 70% after heating for 6 hours at 100?.The light stability of monascus pigment is poor,the sunlight has a great influence on the stability of monascus pigment,and the ultraviolet light and indoor natural light have little influence on monascus pigment.Monascus pigment is sensitive to metal ions,copper ions and ferrous ions have a significant effect on the stability of pigment,calcium ions have a certain effect on the stability of monascus pigment,while sodium ions,magnesium ions and potassium ions have no effect on the stability of pigment.