A ring the phylum level s level (B).Tofu (T),peht of sufu for day (DO),5 days (D5),1 month (MI),2 months (M2),3 months (M3) entation stage than the pr ntatio Functionall duce yoghurt (iicet).It was reported that s.her netal was dai cantly correlated to six carbonic d to pro ver chit of sh at al As ment rlier.t of P ing the amp he thus the dant beforeMI but finally declined to less than 2%and earch.during th pehtze stages.the content ir may inf ce the different flavors of liquor from different regions n of St oup of lab found in ere used to ferment various food and drinks,such as and the fermentation stage than the pre-fermentation stage. Functionally, Pseudomonas was found significantly correlated to six carbonic com￾pound metabolites and all the nitrogenous metabolites except lysine (Li et al., 2017). As mentioned earlier, the function of Pseudomonas to metabolize lysine can be supplemented by Enterobacter. Empedobacter were very abundant before M1 but finally declined to less than 2%, and they were also found in fermentation starter used to brew Xiaoqu liquor and may influence the different flavors of liquor from different regions (Wu et al., 2017). Streptococcus were used to ferment various food and drinks, such as soy and yoghurt. For example, Streptococcus thermophilus is found in fermented milk products and it is classified as a lactic acid bacterium to produce yoghurt (Kiliç et al., 1996). It was reported that S. thermophilus can also be used to produce antioxidant and recover chitin in the fer￾mentation of shrimp head (Mao et al., 2013). S. thermophilus could be used efficiently in deproteinizing the shrimp head thus the content of amino nitrogen increased continuously during the fermentation. In our research, during the pehtze stages, the amino nitrogen content in￾creased to the peak, this was consistent with the deproteinization function of Streptococcus. Weissella belong to the group of LAB found in many fermented foods, including soy sauce, fermented soybean and sausage, and they were very important microbes in many fermented food, which were used to improve food quality and shorten the fer￾mentation period (Ammor and Mayo, 2007). Weissella paramesenteroides Fig. 5. Relative abundance of bacterial composition in sufu samples during the fermentation process at phylum level (A) and genus level (B). Tofu (T), pehtze which inoculated with A. elegans for 24 h (A24), 48 h (A48), salt-pehtze (S), fermentation of sufu for 0 day (D0), 5 days (D5), 1 month (M1), 2 months (M2), 3 months (M3). D. Xu, et al. Food Microbiology 86 (2020) 103340 7