EFFECT OF UV RADIATION AND TRISODIUM PHOSPHATE ON BACTERIAL DECONTAMINATION OF CHICKEN FILLETS

EFFECT OF UV RADIATION AND TRISODIUM PHOSPHATE ON BACTERIAL DECONTAMINATION OF CHICKEN FILLETS

H.F.A. EL-DOSOKY; SHERIN S. MOSTAFA and S. SHAFIK

Animal Health Research Institute, Mansoura Laboratory, Mansoura,Egypt.

INTRODUCTION

Chicken products can be contaminated during preparation with pathogens as E. coli, Salmonella spp. and C. jejuni which are present in chicken intestine Anang et al. (2007)and Hong et al. (2008). There was a growing interest in using UV radiation for food preservation particularly as UV disinfection does not require chemicals or heat and relatively inexpensive McDonald et al. (2000) and Lamikanra et al. (2005) added that UV technology used as an alternative to chemical sterilization in food products and soWallner et al. (1994) and FDA (2007) stated thatUV 220-300nm has germicidal effect on the surface of fresh meat and poultry and approved for use on food products to control surface contamination. Berrang et al. (2001) not detect Coliforms and E. coli while total aerobic count in breast meat were 1.3 log₁₀ cfu/gm.F.S.I.S. (1992) and Capita et al. (2002) mentioned that 8-10% TSP (PH>11.5) were effective in poultry carcass decontamination, while UV kills bacteria by cell wall degradation Bachman (1975). Somers et al. (1994) and Federight et al. (1995)stated that (10-12% TSP) reduce total aerobes, E.coli and Enterobacteriaceae by more than2log cycles in poultry carcass.Stermer et al. (1987) reported 2 log reduction in bacteria on fresh beef by UV radiation. Susan et al. (1995) concluded that UV radiation reduce 80.5%of the inoculated poultry skin with S. typhimurium.Wang   et al. (1998) and Zeong et al. (1998) declared that spraying chicken carcass with 10% TSP reduce the total aerobes by 0.74 log₁₀ cfu /carcass and                S. typhimurium decreased by 2log cycles.Gabriela    et al. (2001) proved that 12% TSP and UV for 25min. reduce APC by 1.03 and 1.60 log cfu/egg, while UV exposure for 1hr gives no growth.Whyte et al. (2001), applied 10%TSP for 15 seconds. which reduce E.coli and Enterobacteriaceae by 1.95 and 1.86 log₁₀ cfu/gm. Kim et al. (2002)stated that UV at 254 nm reduce inoculated skinless chicken with        S. typhimurium and E.coli O₁₅₇: H₇ by 0.07 and 0.24 log cfu/cm² after one minute and 0.22 and 0.26 log cfu/cm² for two minutes. Guerrero and Babosa (2004) stated that UV reduce the microbial loadby blockage DNA transcription and replication. Isohanni and Lyhs (2009) achieved 0.7 log cfu/ml reduction for C. jejuni by UV light on broiler fillets. Chun et al. (2010)obtained reductions of 1.26 and 1.19 log₁₀cfu/gm for C. jejuni and S. typhimurium by UV treatment of chicken breast, while UV light (254nm) at 0.5-0.4 J. /cm reduce cocktail of Salmonella spp., L.monocytogenes and Staph. aureus on breast fillets by 0.4 log cfu/gmSommers et al. (2010) and Haughton et al. (2011) mentioned that raw chicken fillets treated with UV at 0.192J/cm² reduce E.coli, total viable counts and enterobacteriaceae by 0.98, 1.76 and 1.29 log cfu/gm and fillets color was not significantly affected. Keklik et al. (2011) achieved reduction from 0.87-1.43 log cfu/ml rinse solution after 30-180s treatment by pulsed UV light where the temperature ranged from 11.1-44.1⁰c.

MATERIALS and METHODS

A- Sampling:

A total number of 100 chicken breast fillets were collected from an automatic poultry processing plant in Dakahlia, Governorate after complete preparation, the chicken breast fillets were packed in polyethylene film pack and stored at 4⁰C and used for the experiment upon receipt to the laboratory. The examined samples were divided into five groups (20 chicken breast fillets for each group).The first group were dipped in 10% TSP for 30_S, the second group were exposed to UV irradiation at dose of 0.192 J/cm²and 254nm wave length for one minute, the third group  were exposed to UV irradiation at dose of 0.192 J/cm² and 254nm wave length for three minutes, the fourth group were dipped in 10% TSP for 30_S and left ten minutes till fluid drainage then exposed to UV irradiation at dose of 0.192 J/cm² and 254nm wave length for one minute, the last group were dipped in 10% TSP for 30_S and left ten minutes till fluid drainage then exposed to UV irradiation at dose of 0.192 J/cm² and 254 nm wave length for three min. UV irradiation was performed using unfiltered germicidal emitting lamps, The chicken fillets were placed on a stainless-steel tray and irradiated on both the upper and lower surfaces at a distance of 18cm, six germicidal emitting lamps were placed on both sides and the UV lamps were warmed up for 30 min. before irradiation process. UV intensity was determined using UV radiometer calibrated at 254nm and the UV irradiation dose was changed by altering exposure time. UV irradiation was performed in the darkroom to minimize photoreactivation of the pathogenic bacteria after irradiation.  

B- Bacteiological analysis:

Following TSP&UV irradiation 25gm of each examined samples (before and after treatment) were removed using a sterile scalpel and mixed with 225ml of peptone water (0.1% sterile peptone) in a sterile stomacher bag. The samples were then homogenized using a stomacher for three minutes, filtered through a sterile cheese cloth, and diluted with peptone water for microbial count, after two to six serial dilutions (0.1ml) were spread on specific media to determine the following:

1- The aerobic plate count (APC).

2- Enterobacteriaceae count.

According to the methods recommended by APHA (2001).

3- Most Probable Number (MPN) of Coliforms. 

According to the method recommended by FDA (2005).

The Microbial counts were expressed as log cfu/gm.

RESULTS

Table 1: Log mean viable counts of microbial contamination for the treated chicken fillets with 10% TSP (n=20).

    n=  number of examined samples ,TSP = trisodium phosphate,  red. = reduction, * = the results were significantly important(p<0.05).

Table 2: Log mean viable counts of microbial contamination for the treated chicken fillets with UV for one minute (n=20).

Table 3: Log mean viable counts of microbial contamination for the treated chicken fillets with UV for three minutes (n=20).

Table 4: Log mean viable counts of microbial contamination for treated chicken fillets with 10%TSP&UV for one minute (n=20).

Table 5: Log mean viable counts of microbial contamination for treated chicken fillets with10%TSP&UV for three minutes (n=20)

DISCUSSION

In this study the achieved results showed that the inactivation of bacterial contamination on chicken breast fillets by UV and/or TSP increased significantly (P< 0.05) with increasing UV radiation time or dipping in TSP, where the results in table (1)declared that 10% TSP reduce the APC, Enterobacteriaceae and MPN of coliforms counts from 4.83±0.80, 4.38±0.72 and 3.32± 0.48 to 4.08±0.70, 3.60±0.30 and 2.73±0.48 with mean log reduction 0.75,0.78 and 0.59 log cfu/gm respectively the results were significantly reduced (P<0.05), these results were in accordancewithF.S.I.S. (1992); Somers et al. (1994); Federight et al. (1995); Wang et al. (1998); Zeong et al. (1998); Whyte et al. (2001) and Capita et al. (2002). The results in table (2)suggested that UV radiation can be useful in improving the microbial safety of chicken breast fillets without impairing meat quality where exposure to UV radiation for one minute reduce APC, Enterobacteriaceae and MPN of coliform counts from 4.66±0.34, 4.26±0.70 and 3.11±0.90 to 4.21±0.65, 3.92±0.60 and 2.76±0.85 with mean log reduction 0.45,0.34 and 0.35log cfu/gm respectively. Meanwhile increasing UV exposure time decrease the population of the examined bacteria on chicken fillets where the germicidal properties of UV radiation on bacteria are due to the DNA damage done by UV radiation which causes damage to cross-linking between neighbouring pyrimidine bases In the same DNA strand Sastry et al. (2000). Thus, the formation of hydrogen bonds to the purine bases on the opposite strand is impaired due to the mutation, thereby blocking DNA transcription and eventually leading to cell death Unluturk et al. (2008). The results of bacterial decontamination in table (3) were 4.71±0.53, 4.34± 0.90 and 3.53±0.84 which reduced to 3.92±0.70, 3.70± 0.30 and 2.86 ± 0.78 with mean log reduction 0.79, 0.64 and 0.67 log cfu /gm for APC, Enterobacteriaceae and MPN of coliforms respectively. The results intable (2) & table (3) were reduced significantly when compared with those recorded before decontamination (P<0.05) andsimilarly to those obtained byBachman (1975); Stermer et al. (1987); McDonald et al. (2000); Kim   et al. (2002); Guerrero and Babosa (2004); Lamikanra et al. (2005); FDA (2007); Isohanni and Lyhs (2009); Chun et al. (2010); Sommers et al. (2010); Haughton et al. (2011) and Keklik et al. (2011).                                                                                          

Our results in table (4) clearly showed that UV&TSP decreased the bacterial population on chicken fillets where the counts after dipping in 10%TSP and exposure to UV radiation for one minute reduced from 4.80±0.95, 4.58±0.75 and 3.34±0.78 to 3.50±0.40, 3.27±0.65 and 2.20±0.30 with mean log reduction 1.30,1.31 and 1.14 log cfu/gm for APC, Enterobacteriaceae and MPN of coliforms respectively and after dipping in 10%TSP and exposure to UV radiation for three minutes intable (5)the counts were reduced from 4.76±0.38, 4.41±0.04 and 3.36±0.90 to 3.32±0.30,2.87±0.48 and 1.85±0.30 with mean log reduction 1.44,1.54 and 1.51 log cfu/gm respectively, the results were significantly reduced in comparison with those recorded before decontamination (P<0.05) and were in accordance with those obtained by Gabriela et al. (2001); Kim et al. (2002); Isohanni and Lyhs (2009) and Haughton et al. (2011) However few studies have been conducted on the application of UV&TSP for the inactivation of bacterial contamination in chicken fillets.

In summary, the germicidal effect of 10% TSP & UV treatment applied on the surface of raw boneless skinless chicken breast fillets reduce the number of bacterial cells significantly. Thus 10 %TSP & UV radiation process could be used in raw poultry processing plants to lessen the contamination chances of fully prepared poultry products.

REFERENCES

American Public Health Association (APHA) (2001):Compendium of methods for the microbiological       examination of food, Washington, DC

Anang, D.M.; Rusul, G.; Bakar, J. and Ling, F.H. (2007): Effect of lactic acid and lauricidin on the survival of L. monocytogenes, S. entertidis and E. coli O₁₅₇; H₇ inchicken breast stored at 4⁰c. Food control, 18 (8), 961-969.

Bachman, R. (1975): Sterilization by intense UV radiation. Brow Boveri Rev. 62: 206-209.

Berrang, M.E.; Ladely, S.R. and Buhr, R.J. (2001): Presence and level of Campylobacter, Coliforms, E. coli and total aerobic bacteria recovered from broiler parts with and without skin. J. Food protection, 64; 2: 184-188.  

Capita, R.; Alonso-Calleja, C.; delCaminoGarcia-Fernandez, M. and Moreno, B. (2002):Activity of trisodium phosphate compared with sodium hydroxide wash solutions against L. monocytogenes attached to chicken skin during refrigerated storage. Food Microbiology. 19 (1), 57-63.          

Chun, H.H.; Kim, J.Y.; Lee, B.D.; Yu, D.J. and Song, K.B. (2010): Effect of UV-C irradiation on the inactivation of inoculated pathogens and quality of chicken breasts during storage. Food Control, 21: 276-280.

Federight, M.; Cappelier, J.M.; Rossero, A.; Coppen, P. and Denis, J.C. (1995): Evaluation de l ^,effect d^,un traitment de decontamination de carcasses de poulets, vis-à-vis des Campylobacter thermotolerants. Sci. Aliment. 15: 393-401.          

Food and Drug Adiministration (FDA) (2005): Staphylococcusaureus, Bad Bug Book, Foodborne Pathogenic Microorgaisms and Natural Toxins Handbook (1992 / updated 2005), USFDA/FDA, Center for Food Safety & Applied Nutrition.

Food and Drug Adiministration (FDA) (2007):Irradiation in the production processing and handling of food;21 CER. Part 179.39. Code of Federal Regulations, 3: 439-440. 

Food Safety and Inspection Service (F.S.I.S.) (1992): Permits Trisodium Phosphate in poultry plants. Food Safety and Inspection Service Background Document. October.

Gabriela, Z. Favier; Maria, Escudero E. and Ana, M.De Guzman (2001): Effect of chlorine, sodium chloride, Trisodium phosphate and Ultraviolet radiation on the reduction of Yersinia enterocolitica and mesophilic aerobic bacteria from eggshell surface. J. of Food Protection, 64; 10: 1621-1623.  

Guerrero-Beltran, J.A. and Babosa, G.V. (2004): Review; advantage and limitations on processingfood by UV light. Food Sci. Technol. Int. 10: 137-147.    

Haughton, P.N.; Lyng, J.G.; Cronin, D.A.; Morgan, D.J.; Fanning, S. and Whyte, P. (2011): Efficacy of UV light treatment for the microbiological decontamination of chicken associated packaging and contact surfaces. J. Food Protection, 74; 4: 565-572.

Hong, Y.H.; Ku, K.J.; Kim, M.K.; Won, M.S.; Chung, K.S. and Song, K.B. (2008): Survival of E. coli O₁₅₇;H₇ and inoculated on chicken by aqueous chlorine dioxide treatment. J. Microbiology and Biotechnology, 18(4): 742-745.      

Isohanni, P.M. and Lyhs, U. (2009): Use of Ultraviolet irradiation To reduce C. jejuni on broiler meat. Poultry Sci. 88: 661-668.                        

Keklik, N.M.; Demirci, A. and Bock, R.G. (2011):Surface decontamination of whole chicken carcasses using Pilot-Scale pulsed UV light system transactions of the ASABE.54; 4: 993-1000.                                               

Kim, T.; Silva, J.L. and Chen, T.C. (2002): Effect of UV irradiation on selected pathogens in peptone water and on stainless steel and chicken meat. J. of Food Protection, 65; 7: 1142-1145.  

Lamikanra, O.; Kueneman, D.; Ukuku, D. and Bett-Garber, K.L. (2005): Effect of processing under ultraviolet light on the shelflife of fresh cut cantaloupe melon. J. of Food Science, 70; 9: 534-539.

McDonald, K.F.; Curry, R.D.; Clavenger, T.E.; Unklesbay, K.; Eisenstark, A.; Golden J. and Morgan, R.D. (2000):A comparison of pulsed and continuous UV light sources for the decontamination of surfaces. IEEE Trans. Plasma Sci. 28: 1581-1587.

Sastry, S.K.; Datta, A.K. and Worobo, R.W. (2000): Ultraviolet light, Journal of Food Science Supplement. 65, 12: 90-92. 

Somers, E.B.; Schoeni, J.I. and Wong, A.C.L. (1994): Effect of trisodium phosphate on biofilm and planktonic cells of C. jejuni, E.coli O₁₅₇H₇; L. monocytogenes and S. typhimurium. Int. J. Food Microbiology. 22: 269-276.

Sommers, C.H.; Sites, J.E. and Musgrove, M. (2010):Ultraviolet light (254nm) inactivation ofpathogens on foods and stainless steel surfaces. J. Food Safety 30; 2: 470-479.  

Stermer, R.A.; Lasater-Smith, M. and Brasington, C.F. (1987): Ultraviolet radiation and effective bactericide for fresh meat. J. Food Protection 50: 108-111.

Susan S. Sumner; Eva, A. Wallner-Pendleton; Glenn W. Froning and La Verne E. Stetson (1995): Inhibition of S. typhimurium on agar medium and poultry skin byultraviolet energy. J. Food Protection, 59; 3: 319-321.

Unluturk, S.; Atilgan, M.R.; Baysal, A.H. and Tari, C. (2008): Use of UV radiation as a non-thermal process for liquid egg products (LEP) Journal of engineering. 85; 4: 561-568.

Wallner-Pendleton, E.A.; Sumner, S.S.; Froning, G.W. and Stetson, L.E. (1994): The use of Ultraviolet radiation to reduce Salmonella and psychrotrophic bacterial contamination on poultry carcasses. Poultry Sci., 73: 1327-1333.                                   

Wang Weichi; Li Yan Bin; Slavik, M.F. and Hua Xiong (1998): Trisodium phosphate and Cetylpyridinium chloride spraying on chicken skin to reduce attached S. typhimurium. J. Food Protection. 60; 8: 992-994.       

Whyte, P.; Collens, DJ.; McGill, K.; Monahan, C. and O^,Mahony, H. (2001): Quantitative investigation of the effects of chemical decontamination procedures on the microbiological status of broiler carcasses during processing. J. Food Protection. 64; 2: 179-183.                                              

Zeong P.Y.; Yanbin, L.I. and Michael, S. (1998):Use of antimicr- obial spray applied with inside-outside bird washer to reduce bacterial contamination on prechilled chicken carcasses. J. Food Protection 61; 7: 829-832.