Abstract: In order to solve the problem of acidification in restaurant food waste anaerobic fermentation (RFWAF). Different proportions of household food waste (HFW) and biogas residue biochar were added as conditioning agents into the acidogenic reactor. The effects of two conditioners on pH, total volatile fatty acids (TVFAs) and dissolved protein concentrations of restaurant food waste during the process of RFWAF acidification and acidification were studied. The results showed that biogas residue biochar could promote the accumulation of TVFAs and decrease the concentration of dissolved protein，which could not alleviate acidification. Although adding HFW promoted the accumulation of TVFAs, it also improved the content of dissolved protein in fermentation liquid. Under the condition of 15%TS , when the mass of household food waste addition were 1∶3，1∶1，3∶1, the average protein concentration increased by 27.7%, 55.2% and 58.9% compared with control group, respectively. Therefore, the anaerobic fermentation acidification could be alleviated and pH could be maintained stable by improving the alkalinity of the system.

Key words: restaurant food waste, anaerobic fermentation, household food waste, biogas residue biochar, acidifying