Rutin's natural source Flos Sophorae as potential antioxidant and improver of fungal community in Chinese sausages

Abstract Chinese sausages are susceptible to lipid oxidation and growth of undesirable pathogenic microorganisms, while plant polyphenols rutin could act as a novel natural preservative due to exerting antioxidant and antibacterial properties. Thus this study investigated the effect of adding rutin (0.05% or 0.1%) or its natural source Flos Sophorae (0.2%) on the quality and microbiome of Chinese sausages. Results indicated that the Chinese sausages fortified with rutin or Flos Sophorae showed lower hardness, chewiness, thiobarbituric acid reactive substances and acid values, higher moisture, pH, DPPH scavenging activity and fungal diversity, with higher beneficial ( Incertae_sedis_Saccharomycetales and Mucor ) and lower harmful fungi numbers compared with the control. But rutin addition decreased color scores and redness, whereas increased lightness and yellowness values, and reduced the numbers of predominant bacteria Staphylococcus at the low level and bacterial diversity at the high level. However, the supplementation of Flos Sophorae further elevated antioxidant state compared with rutin groups, without significant defect of bacterial community and color traits in Chinese sausages. Taken together, these results demonstrated that rutin's natural source Flos Sophorae could be as a potential antioxidant and improver of fungal community in Chinese sausages.