Abstract:The key processing technology of fresh lettuce including, pre-cooling, cutting, sterilization, preservation, centrifugal dehydration, modified atmosphere packaging (MAP) and storing. Respiration intensity and sterilization effect were determined to optimize the process parameter of the preservation and sterilization. The results showed that the fresh lettuce treated with pre-cooling for 12 hours under 10 ℃, 60 mg/L acetic acid, 50 mg/L peroxyacetic acid and 20 mg/L H2O2 for 2 minutes, 0.2% citric acid and 6% calcium ascorbate for 2 minutes, then centrifugal dehydration and MAP with 4%O2, 5%CO2 and 91% N2. The shelf life of the fresh lettuce would be 10 days under 10 ℃.
