Research on Extraction Technology of Protein from Waste Beer Yeast

[Objective]The aim was to study the best extration method and technology of protein from waste beer yeast.[Method]Four extraction methods were adopted in this research,which were ultrasonic extraction,freeze-thaw extraction,salt extraction and alkali extraction.[Result]Under the best extraction process and conditions,the protein extraction rate of ultrasonic extraction,freeze-thaw extraction,salt extraction and alkali extraction were 3.47%,4.15%,5.66% and 22.81% respectively.The best extraction technology of protein from beer waste yeast was alkali extraction,the best conditions of alkali extraction were 3∶10 of yeast to liquid ratio,1% of NaOH concentration,1 h of extraction time and 60 ℃ of extracting temperature.[Conclusion]It might provide the theoretic and experimental foundation for the extraction of protein from beer waste yeast in large scale.