The Antibacterial Effect of Flower Pollen on E scherichia coli O 157: H 7 in Ground Pork

This study was conducted to confirm the synergistic inactivation effect of flower pollen when applied with heat treatment to E scherichia coli   O 157: H 7. The reduction of the number of E . coli   O 157: H 7 was monitored during heat treatment at 55, 57.5, 60, 62.5 and 65 C . The D ‐values in the culture were D 55  = 10.03 ± 0.59, D 57.5  = 3.84 ± 0.05, D 60  = 2.76 ± 0.19, D 62.5  = 1.31 ± 0.20 and D 65  = 1.04 ± 0.01 min, respectively, which were reduced to D 55  = 3.13 ± 0.12, D 57.5  = 3.02 ± 0.14, D 60  = 1.80 ± 0.05, D 62.5  = 1.11 ± 0.03 and D 65  = 0.79 ± 0.01 min with the addition of pollen (80 mg/m L ). The z‐value without addition of pollen was 10.24 C , which increased to 15.11 C with addition of pollen. The D ‐values in ground pork were D 55  = 5.59 ± 0.11, D 57.5  = 2.58 ± 0.05, D 60  = 2.07 ± 0.19, D 62.5  = 1.30 ± 0.03 and D 65  = 0.87 ± 0.02 min. When treated with the addition of pollen (150 mg/m L ), the D ‐values decreased to D 55  = 1.87 ± 0.05, D 57.5  = 1.56 ± 0.02, D 60  = 1.11 ± 0.01, D 62.5  = 0.73 ± 0.01 and D 65  = 0.50 ± 0.00 min. The z‐value increased from 13.05 C to 16.86 C . Practical Applications To the best of our knowledge, this is the first study applying flower pollen as a natural antimicrobial additive to improve the effect of heat treatment at the time of the sterilization of a meat product. Flower pollen might be provided by cultivating plant resources. It implies that the cost of flower pollen could be dramatically reduced and the cost reduction with suitable degree of antimicrobial activity gives a great benefit to the users in the processed food industries.