Abstract:In this paper，the new corn steeping technology of and studying structure composition and changing rule of microflora in corn steeping process were studied.H2O2and lactic acid were used to co-steep corn，the optimal steeping conditions were determined by orthogonal experiment，and the diversity of bacteria in the steeping process was analyzed by Miseq high-throughput sequencing technology.Orthogonal test showed that the optimal conditions for steeping corn were initial lactic acid concentration of 0.6%，lactic acid action time of 16 h，H2O2concentration of 3%，and H2O2action time of 22 h.Under the optimal conditions，the starch yield increased from 56.02%to 68.53%，and the steeping time was shortened by 32 h.The results of Miseq highthroughput sequencing analysis showed that the bacterial structure and composition were relatively rich at the early stage of immersion.After a period of time，Lactobacillaceae grew and became the dominant species，accompanied by the reduction of operational taxonomic unit （OUT） level.At the end of immersion，Lactobacillaceae entered the decline period，and the number of other bacteria significantly increased.By analyzed the correlation between the community structure of the bacteria in the steeping solution and the environment，it was found that the influencing factors causing the differences in the colony structure were lactic acid content，glucose content，the pH of the steeping solution，and steeping temperature in turn.