Characteristic of meat colour of different duck populations
Abstract. Out of 6 conservative flocks (Khaki Campbell – Kh1, Orpington – O1, Miniducks – K2, Polish Pekin – P33, Pekin originated from Danish – P8 and cross-breeds in Pekin type – SB) 60 female ducks were used for comparison (10 ducks in each group). Birds were slaughtered at 7 week of age.
The investigation of breast muscles covers: determination of the colour parameters L* (lightness), a* (redness), b* (yellowness), C (saturation), ho (hue) and ΔE (colour difference), total haem pigments’ content (THP) including myoglobin (Mb), oxymyoglobin (MbO2) and metmyoglobin (MMb) content. Sensory evaluation of raw muscles’ colour intensity in 10 point scale and Principal Component Analysis (PCA) of all measured parameters were also performed.
Low THP and MbO2 were shown by Kh1 and P33 (THP: 3.79 and 3.74 mg/g, MbO2: 2.32 and 2.46 mg/g respectively). They were also characterized by the highest L* value of the all flocks (45.27 and 44.25 respectively) (P≤0.01, P≤0.05).
The Kh1 was evaluated by the sensory panel as the lightest (5.01 conventional units [CU]) (P≤0.01). However P8 and K2 were assessed as darker than Kh1 and P33 (6.12 and 6.22 CU vs. 5.01 and 5.71 CU) (P≤0.01, P≤0.05) and also had significantly higher pigments content (4.48 and 4.57 mg/g respectively) (P≤0.01). Additionally K2 was characterized by the highest MMb content (0.48 mg/g) (P≤0.01), but this value is below the level that makes the colour undesirable. The ΔE values between flocks were in the 1.02–2.86 range. With just few exceptions, flocks with ΔE value higher than 2, differed significantly in pigments content, L* parameter, and sensory panel scores. As regards the obtained results Kh1 and P33 appeared significantly lighter than P8 and K2. Kh1 and P33 had lower pigments content, higher L* value and were assessed by a sensory panel as having lower colour intensity than P8 and K2. PCA analysis confirmed ANOVA results and also indicated large total colour variation of the samples within breeds except of O1 muscles.
