meat colour in fighting bulls
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- 1. Meat colour of fighting bulls.B. Hernndez, G. Lisazo, A- Horcada, M.J Berian and A. PurroyEscuela Tcnica superior de Ingenieros Agrnomos, Universidad Publica de Navarra.
2. Fighting bulls are subjected to both physical and emotional stress before their death, conditions know to affect quality of meat.
Meat from stressed or excessively fatigued animals has a high pH (>6.0 as oposed to 5.4 5.8 in normal meat) and a dark colour.
The aim of thiswork is to characterise the meat of fighting bull, studyhowageingchanges meat colour and investigate the stability of colour or shelflife of thiskind of meat in comparisonwithothertypicalcommercial beef breed.
3. Material and Methods
Fourteen 4 yroldrunning bulls selected from The Fiesta of San Ferminwere
studied. Theywereslaughteredby a swordwound in the bullring.
Theseanimalswerecomparedwith 15 bulls of Pirenaica breedslaugthered
at 12 13months of age.
Longissimusdorsimusclewas removed from the
lefthalf of he carcass 24 hourspost-mortem.
The pH of Longissimusdorsimusclewas
Measured at 24 hours post-mortem with a pH
meter with a penetrationprobe.
Reflectancespectra and CIE L*a*b coordinates, hue and chroma (C*) weredeterminedusing a MINOLTA CM-2002 with a D65 illuminant and 10 observed at three different periods of time: after 24 hours of oxigenation,5 days post mortem and 7 days post mortem
Colour wasalsodeterminedthroughchemicalparameters, i.e.content of myoglobinderivates (deoxymioglobin, oxymioglobin, and metmyoglobin)
Total content of myoglobinwasdeterminedusing a SHIMAZU UV-2001 PC spectophotometer
Analysis of variancewasperformedusing the SPSS 6.1.2 statisticalpackage.
5. Results and Discussion
6. Table 1. Values of liveweight, myoglobincontent and pH in Longissimusdorsimuscle of Fighting bulls and Pirenaica breed bulls
- Colour of meat from fighting bulls wasdarker, redder and more purple than that of beeffrom Pirenaica breed (P
Thisfact is in agreementwithwhatcouldbeexpected in meat that has sufferedsuch a stressingtreatment.
8. Table 2. Evolution of colourcoordinates CIE L*, a*, b*, hue h* and Chroma C* ( standarddeviation), in fighting bulls and Pirenaica breed bulls (n=15) after 24 hours of oxigenation (Day 1) fivedays post mortem and sevendays post mortem.
- Meat of fighting bulls has L* valueslower than those of beef from Pirenaica group at different periodos of time (P6 whileall
thosecatalogued as normal have pH