Use Of Lactobacillus To Reduce The Benzo(a)pyrene Of Processed Meat Products

Lactobacillus pentosaceus ML32 and Lactobacillus plantarum 121 have been confirmed to bind benzopyrene(B(a)P) by physical adsorption very well. Their benzopyrene adsorption rate is 64.9% and 65.9%, respectively. However, it is not clear if they have good ability to remove benzopyrene from processed meat products via the best removal. Therefore, the objectives of this study were to:(1) establish a detection method of benzopyrene extracted from the processed meat;(2) evaluate the possibility of 2 lactobacilli strains ML32 and 121 to remove benzopyrene from fried, smoked, and grilled meats;(3) discuss the effects of meat types and fat contents on the benzopyrene removal of two strain ML32 and 121; and(4) try to explain the benzopyrene removal mechanism by Lactobacillus strains in terms of infrared-scanning wavelength variation of benzopyrene in processed meat products. This present study is designed to look for Lactobacillus strains as a new biological agent to reduce the occurrence of benzopyrene, a harmful chemical which causes processed meat products to be unsafe. The following are main results.1. The percentage of B(a)P-absorbing was s 65.9% for strain 121 and 64.9% for strain ML32. In simulation of processed meat systems, strains 121 and ML32 removed 31.75% and 32.83% B(a)P, respectively. They removed benzopyrene subjected to meat products in three simulated conditions well. A pretreatment of B(a)P plus bacterial cells decreased effectively the presence of benzopyrene in processed meats. The percentage of B(a)Premoving by strains 121 and ML32 was 50.57% and 38.75%, respectively. The more bacterial cells, the more removed benzopyrene was observed in a pretreatment of bacterial cells, benzopyrene plus meats. However, the benzopyrene removal rate was strain-depending. Strain ML32 adsorbed benzopyrene more than strain 121 did.2. The removal of benzopyrene by strains 121 and ML32 was same either in fried and smoked or grilled meats. A extension of processing time and temperature led benzopyrene removal to become a high level of depression parabola. Benzopyrene from the meat was fried directly in oil was reduced more due to more generated B(a)P by lactobacilli strains than that from the meat fried indirectly. The B(a)P- removing of strain 121 was higher in direct smoked meat than in indirect smoked meat, but strain ML32 was opposite. Both strains had higher B(a)P removal in the direct grillied meat than in indirect grillied meat.3. Types of processed meats led two lactobacilli strains to have different benzopyrene removal percentages, but their B(a)P- removing rate was more than 30%. The percentage of B(a)P removed by strain 121 in smoked sausage was 39.41%, and 31.75 % in fried chicken meat. B(a)P removal rate of strain ML32 in fried chicken reached 35.44%. The higher the fat content, the higher B(a)P- removing rate of two strains 121 and ML32. In the presence of 100% fat content, the cells of strains 121 and ML32 removed 68.07% and 66.41% benzopyrene, respectively.4. The infrared scanning wave length and peak of benzopyrene changed when benzopyrene was added to processed meats compared to the control, indicating that some meat components might remove partly benzopyrene. Moreover, a very significant change in the infrared scanning wave length and peak of benzopyrene removal, after processed meat was treated by two lactobacilli strains, was observed. It means that lactobacilli strains might interfer the processed meat to remove benzopyrene. Analysis of HPLC also confirmed that a loss of benzopyrene took place in the meat products treated by the two bacterial cells.5. Peptidoglycan liberated from the cell wall of the two strains played a key role in benzopyrene adsorption. The higher concentration of peptidoglycan, the more benzopyrene was absored. A whole peptidoglycan structure had the highest efficiency of the B(a)P-adsorption rate. The adsorption percentage of benzopyrene declined once the peptidoglycan structure of bacterial cell wall was destroyed.In conclusions, both L. pentosus ML32 and L. plantarum 121 showed good ability to remove benzopyrene from processed meat via its physical binding. They should be helpful candidates to be used as a biological agent to reduce the benzopyrene of food system.