 In this study, Fourier transform infrared, PFTAR, spectroscopy was used to analyze the composition of biomass and its derivatives during processing. The results showed that solvents, chemicals, enzymes, and potentially formed degradation by products were present in the biomass conversion process. These findings will help researchers better understand the FTR analysis results of processed biomass. This article was authored by Jingxuan Zhuang, Mili, Yunchao Pu, and others.