Improvement of chilling efficiency and product quality of broiler carcasses using sub-zero saline solutions

Transcription

1 Improvement of chilling efficiency nd product qulity of roiler crcsses using su-zero sline solutions I. Kng*, M.M. Metheny*, nd PhD, H.C. Lee*, PhD, D. Bennett *, PhD, S. Hurley, PhD, Animl Science*/Agriusiness Sn Luis Oispo, CA 935 Introduction Crcss chilling in suzero sline solutions hs not een studied enough lthough it cn trnsfer the crcsses temperture to the chilling medi in n efficient wy. In197, Jnky et l. compred roiler qulity fter no chilling for hot-pckged crcsses, fter chilling overnight in 5% NCl solution t -1 C, nd fter chilling overnight in ice slurry t 1 C. The rest fillets from NClchilling showed lower sher force, higher moisture content, higher cooking yield, nd etter sensory ttriutes thn the ice-slurry chilling or no chilling. However, the overnight chilling is too long to chill nd resulted in wter nd rine pickup y 5.1 nd.3% respectively, which re not desirle nowdys. When roilers were chilled for h, rest fillets in 5% NCl solution t -1 C showed more wter nd sodium sorption thn the fillets in wter t 1 C (Hoey et l., 193). No study hs een conducted to chill roiler crcsses in su-zero rine solutions with vrious slt contents. Therefore, the purpose of this reserch ws to investigte the effects of su-zero rine chilling on chilling efficiency nd product qulity of roiler crcsses. Mterils nd methods Brine chilling solution, rine ice preprtion, nd roiler crcss chilling In this study, three experiments were conducted to chill roiler crcsses using different sline solutions nd chilling tempertures in the Met Processing Center t Cliforni Polytechnic Stte University (Cl Poly, Sn Luis Oispo, CA) or in locl poultry processing plnt. Prior to crcss chilling, rine solutions (w/w) were prepred in gllon continers nd plced in freezer room t -3 C. Eviscerted roiler crcsses were tgged, weighted, nd chilled y sumersing in one of the prepred chilling solutions with mechnicl gittion. Before chilling, one medium crcss per chilling ws selected to monitor the internl rest temperture every 5 min until the crcss temperture reched ~ C, using digitl thermometer logger. During chilling, regulr or rine ice ws dded to mintin the trget solution tempertures. After chilling, crcsses were hung for 5 min drin nd weighed for post-chill weight. Experiment I: roiler crcss chilling using rine solution t, nd % A totl of 7 mle roilers (Ross 7, pproximtely 5 dys old) were used for 3 replictions ( irds/repliction) in three different dys. Birds were rndomly picked from the processing line in locl processing plnt fter eviscertion or fter pre-chilling. Those irds were sujected to one of three chilling tretments s following: one ice slurry control (% NCl/.5 C) nd two sline solutions (% NCl/-.1 C nd % NCl/-5. C) for chilling roilers immeditely fter eviscertion or fter pre-chilling (% NCl/1 C) in the plnt. Experiment II: roiler crcss chilling using rine solution t, 1,, nd 3% A totl of 3 mle roilers (Ross 7, pproximtely 5 dys old) were used for 3 replictions (1 1

2 irds/repliction). After 1 h feed withdrwl, irds ws trnsported from the Poultry Unit to the Met Processing Center t Cl Poly. Ech ird ws shckled, electriclly stunned for 3 s ( ma, Hz, 1 V), nd led for 9 s y severing oth crotid rtery nd jugulr vein on one side of the neck. Birds were then sujected to sclding, defethering in rotry drum picker for 5 s, mnul eviscerting, nd wshing. Resulting crcsses were hung for 5 min drin, weighed for pre-chill weight, nd sujected to chilling fter wing tg. Experiment III: Crcss chilling using rine solution t, 3 nd % A totl of mle roilers were otined in locl processing plnt for replictions (1 irds/repliction). Ech ird ws weighted, tgged, nd chilled s similr in Experiment I, using one of three chilling solutions: 1) ice slurry control t.5 C, ) 3% slt rine solution t -1. C, nd 3) % slt rine solution t -. C. ph, R-vlue, nd srcomere length The ph vlue of rest muscle ws mesured with ph electrode to ph meter, using the iodocette method of Sms nd Jncky (19). R-vlue (rtio of inosine:denosine) ws ssessed s n indictor of denosine triphosphte (ATP) depletion in the muscle using the method of Thompson et l. (197). Srcomere length ws evluted for the sttus of muscle contrction using lser diffrction method (Cross et l., 19). Cooking yield nd sher force For cooking yield nd sher force, left fillets were removed t h post mortem per tretment, which were weighed nd plced on stinless trys on stinless steel rck. The fillets were cooked to n internl temperture of 7.7 C in preheted convection oven t 177 C following USDA- Food Sfety nd Inspection Service (1) guidelines. Temperture ws monitored with thermocouples inserted to the thickest prts of rest smples on trys. After cooking, the fillets were individully wrpped with foil nd stored overnight t 3 C in plstic gs. The following dy, the cooked rests were rought to room temperture nd weighed gin to determine cooking yield. Sher force ws determined ccording to the rzor-lde method descried y Cvitt et l. (). A texture nlyzer ws clirted with 5-kg lod cell. The rzor lde (height, mm; width, mm) ws set t mm/s, nd the test ws triggered y -g contct force. The sher force vlue ws clculted s the mximum force recorded during the sher. Two sher force mesurements per rest fillet were mde. Sttisticl nlysis: All experiments were conducted for 3 times. Dt were evluted y onewy ANOVA, using PASW 1 sttistic progrm nd completely rndomized design. A post-hoc nlysis ws performed using Duncn s multiple rnge test to evlute difference mong tretments (P <.5; SPSS, 11). Results nd Discussion Experiment I Sher force: To compre the chilling effects of su-zero sline solutions on rest tenderness, one control (% NCl/.5 o C) nd two slt solutions (% NCl/-.1 o C nd % NCl/-5. o C) were used to chill crcsses with/without pre-chilling in % NCl/1 o C. Fillets from the crcsses chilled in % NCl/-.1 o C significntly improved tenderness y reducing the sher

3 TEMPERATURE ( ) force (1 1 N) of control to the level of.1 to.7 N (P <.5), with no significnt difference oserved for % NCl/-5. o C (P >.5), regrdless of pre-chilling (Figure 1). Experiment II Crcss chilling time: Broiler crcsses were chilled using one ice slurry control (% NCl/.5 C) nd three slt solutions (1% NCl/-. C, % NCl/-1. C, nd 3% NCl/-1. C) tht were selected sed on the results of Experiment I. The internl temperture of eviscerted crcsses ws ~ C tht ws continuously reduced to. ~.7 C during chilling, with verge chilling times for 115,, 95, nd 9 min in wter control t.5 C nd three rine solutions (1% NCl/-. C, % NCl/-1. C, nd 3% NCl/- 1. C), respectively (Figure ). These results indicted tht 3% NCl reduced the chilling time of the wter control y 5 min (or %), with the intermedite reduction (13 ~ 17%) seen for other NCl solutions. Recently, Snswt (1) reported tht wter chilling time of roiler crcsses ws min which ws shorter thn the current study (115 min). The difference is elieved to e due to the crcss weights etween the previous (1.7 kg) nd the current (.5 kg) studies. 1 SF 1 1 % NCl % NCl % NCl % NCl/1 o C.5 o C -.1 o C -5. o C % NCl % NCl % NCl o C -.1 o C -5. o C Figure 1. Effects of roiler chilling temperture, slt content nd chilling method on sher force of roiler rest fillets 5 3 % NCl/.5C 1% NCl/-.C % NCl/-1.C 3% NCl/-1.C CHILLING TIME (MIN) Figure. Temperture chnge profiles of roiler fillets during chilling in wter nd rine solutions. Tle 1. Evlution 1 of crcss chilling yield nd rest fillet property for slt content, ph, R-vlue, srcomere length nd cooking yield (±SEM) fter chilling crcsses in three different chilling solutions Mens within row with unlike superscripts re different (P <.5). 1 The numer of oservtions in ech chilling, n = 1. 3

4 Crcss chilling yield, fillet slt content, nd fillet cooking yield: After chilling crcsses, no significnt difference ws oserved for chilling yield, ph, R-vlue, nd srcomere length in rw fillets s well s cooking yield nd slt content in cooked fillets (P >.5) (Tle 1). Sher force: The sher force vlue of cooked rest fillets ws step-wise decresed from 1.1 to 11.5 N s the slt content incresed nd the chilling temperture decresed from %/.5 C to 3%/- 1. C, with the lowest sher force oserved for 3% NCl/-1.C (P <.5) (Figure 3). In 19, Duke nd Jnky used one wter control nd 7 tretment comintions using three rine chilling solutions (,.5, 5. nd 7.5% NCl), three chilling tempertures (1, 13, 1 o C) nd three chilling steps (15 min/1 C, 15 min/13 C, nd 15 min/1 C). Out of the chilling tretments, the two lowest sher forces were found in the comintion of 5./5./5.% NCl nd.5/5./7.5% NCl, wheres the highest sher force ws oserved in the wter control of //% NCl (Duke nd Jnky, 19). Those chilling methods, however, llowed wter retention from 9 to 1% potentilly due to the 15 min pre-chilling t 1 C followed y 3 min chilling t 13 C (15 min) nd 1 C (15 min). SF % NCl 1% NCl % NCl 3% NCl.5 o C -. o C -1. o C -1. o C Figure 3. Effects of roiler chilling temperture nd slt content on sher force (SF) of roiler rest fillets Experiment III Sher force: To identify the est chilling condition sed on the Experiment I nd II, three slt solutions (, 3, nd % NCl) were selected to evlute the effect of crcss chilling on met tenderiztion. Results indicted tht sher force ws stepwise reduced s NCl incresed from to % nd the temperture decresed from.5 to -.1 o C in the chilling solution (Figure ). Bsed on these results of Experiment I to III, n idel chilling condition for roiler tenderiztion ppers to e % NCl solution t -.1 o C. SF 1 1 % NCl 3% NCl % NCl.5 o C -1. o C -.1 o C Figure. Effects of roiler chilling temperture nd slt content on sher force of roiler rest fillets Conclusions Improvement of poultry chilling efficiency nd product qulity is desirle in poultry processing plnts. In this study, roiler crcsses hve een chilled using vrious sline solution nd chilling tempertures from to % slt nd from.5 to - 5. o C. Broiler chilling efficiency ws significntly improved nd the rest fillet tenderness significntly incresed s the solution temperture reduced from.5 to -5. o C while the slt content incresed from to %, with no significnt difference oserved etween % NCl/-.1 o C nd % NCl/-5. o C. Bsed on these results, roiler crcsses chilled in % NCl/-.1 o C ppers to e idel to improve oth chilling efficiency nd met tenderness compred to the crcsses chilled in % NCl/.5 o C.

5 ACKNOWLEDGEMENTS The uthor thnks Agriculturl Reserch Institute t Cliforni Polytechnic Stte University (Sn Luis Oispo, CA) for providing funding. The uthors lso thnks Foster Frms (Livingstone, CA) for donting roilers. References Cvitt, L. C., G. W. Youn, J. F. Meullent, C. M. Owens, nd R. Xiong.. Prediction of poultry met tenderness using rzor lde sher, Allo-Krmer sher, nd srcomere length. J. Food Sci. 9:SNQ11 SNQ15. Cross, H. R., R. L. West, nd T. R. Dutson. 19. Comprison of methods for mesuring srcomere length in eef semitendinosis. Met Sci. 5:1. Hoey, J. M., M. G. Dukes, nd D. M. Jnky Tenderness nd sodium-content of Pectorlis superficilis from roilers chilled in potssium or sodium chloride ice slush. J. Food Science, :75-7. Jnky, D. M,, A. S., Arf, J. L. Olinger, J. A. Kourger, nd D. L. Fletcher Sensory, physicl, nd microiologicl comprison of rine-chilled, wter-chilled, nd hot-pcked (no chill) roilers. Poultry Science, 57:17-1. Sms, A. R., nd D. M. Jncky. 19. The influence of rine chilling on tenderness of hot oned chill-oned nd ge-oned roiler fillets. Poult. Sci. 5: Snswt, T., H. C. Lee, P. Singh, H. Kim, K. B. Chin nd I. Kng. 1. Comintion of muscle tension nd crust-freeze-ir-chilling improved efficcy of ir chilling nd qulity of roiler fillets. Poult. Sci. 93: SPSS. 11. PASW Sttistics 1 for Windows. SPSS Inc., Chicgo, IL. Thompson, L. D., D. M. Jnky, nd S. A. Woodwrd Tenderness nd physicl chrcteristics of roiler rest fillets hrvested t vrious times from post-mortem electriclly stimulted crcsses. Poult. Sci. : USDA, Food Sfety nd Inspection Service. 1. Retined wter in rw met nd poultry products; poultry chilling requirements, finl rule. 9 CFR, prts 31 nd 1. Fed. Regist. :