关键词: 就地清洗程序；蜡样芽孢杆菌；生物被膜；正交试验；过氧乙酸

Abstract: In this study, using an orthogonal array design, the optimum cleaning-in-place (CIP) regime for thoroughly removing the biofilm of Bacillus cereus A1, which has excellent biofilm-forming ability and high alkali and acid tolerance, on stainless steel sheets was determined as sequential washing with 17.5 g/L NaOH solution at 85 ℃ for 20 min, water, 15 g/L HNO3 at 85 ℃ for 20 min, and water once again. To reduce their use, acid and alkali cleaning agents were used in combination with peracetic acid, and the optimized CIP protocol was determined as sequential washing with 15.0 g/L NaOH solution at 85 ℃ for 10 min, water, 10.0 g/L HNO3 at 85 ℃ for 10 min, 3 g/L peracetic acid at 25 ℃ for 10 min, and neutralizer. This CIP protocol could not only thoroughly remove Bacillus cereu, but also reduce the concentration of acid and alkali cleaning agents and the cleaning time, providing a more efficient and eco-friendly method to clean food processing equipment.

Key words: cleaning-in-place; Bacillus cereus; biofilm; orthogonal array design; peroxyacetic acid