Application of burdock peel concentrate to control microbiologsy in pork

The possible use of burdock peel concentrate as a natural food preservative was studied by examining its antimicrobial effect on the growth of total bacteria and Listeria monocytogenes in pork. The crude fresh and Listeria monocytogenes inoculated pork was treated with burdock peel concentrate (per milliliter concentrate contained 500 mg burdock peel) in various concentration, 250, 500, 750, 1 000 μL/mL. The total bacteria and Listeria monocytogenes count was detected at 0, 12, 24 and 48 h in 25℃ and 0, 1, 3, 5, 7 d in 4℃environment. The organoleptic evaluation was performed to study the organoleptic quality of pork. The transmission electron microscopy (TEM) was used to study the effects of burdock peel concentrate on cellular structure of Listeria monocytogenes. Burdock peel concentrate showed significant (P<0.05) antimicrobial activities against total bacterial and Listeria monocytogenes in pork at 25℃, the antimicrobial activities was correlated positively with its concentration. Pork treated with 500 μL/mL burdock concentrate showed the preferable organoleptical quality. TEM revealed the damage to the bacterial cell walls and cellular content. Based on proven antimicrobial effects, burdock concentrate may have applications as a food preservative.