Abstract:Objective This study developed a preservation process for leisure dried tofu (LD-tofu) by using natural antimicrobial agents, Surfactin and linalool, to replace chemical preservatives.Methods The minimum inhibitory concentration (MIC) of Surfactin and linalool was determined with Bacillus subtilis as the indicator bacteria, and aerobic plate count and sensory score were used as the evaluation indicators to optimize the optimal preservation process parameters of linalool and Surfactin for LD-tofu through single-factor and response surface experiments, and the quality changes of LD-tofu during storage were analyzed.Results The minimum inhibitory volume fraction of linalool was 1.95 μL/mL, and the MIC of Surfactin was 125 μg/mL, respectively. The optimal preservation process parameters of linalool and Surfactin for LD-tofu were Surfactin concentration of 187.5 μg/mL, linalool volume fraction of 2.2 μL/mL, treatment time of 30 min, and material-liquid ratios of 1∶3 (g/mL). Under these conditions, the shelf life of LD-tofu at 25 ℃ could be extended from 2 to 4 weeks. The aerobic plate count within 4 weeks at 4 ℃ could be lower than the detection limit, significantly slowing down the degradation of protein (decrease by 4.09%) and fat (decrease by 6.97%) and inhibiting the production of malondialdehyde (decrease by19.9% compared with the control group).Conclusion Linalool combined with Surfactin can effectively inhibit bacteria and delay the quality deterioration of LD-tofu.