Effect of cold storage terms on physico-chemical characteristics of Japanese quail (Coturnix coturnixjaponica) meat

S. Ribarski, A. Genchev, S. Atanasova
Abstract. The purpose of the study was to investigate the effect of cold and duration of storage at 0–4 °С on the chemical composition and technological traits of Japanese quail (Coturnix coturnix japonica) meat. It was established that water content of the studied muscles varied between 74.28 (m. Pectoralis profundus, MPP) and 75.07% (leg muscles). Protein content was 21.5–22.3% and 20% in breast and leg muscles, respectively. The fat percentage of the different muscles varied within a broad range – from 1.0 to 3.3%. The processes occurring in meat during the cold storage influenced its physico-chemical properties. The most intensive processes were observed during the first 24 hours, when meat pH decreased from 6.06–6.14 to 5.46–5.61 (breast muscles) and from 6.58–6.6 to 6.04–6.06 (leg muscles). By the 72nd post mortem hour, breast and leg meat pH retained 5.33–5.38 and 6.02–6.03, respectively. The lower meat pH reduced the hydrophilicity of muscle proteins and as a result, the water-holding capacity (WHC) by the 24th hour of m. Pectoralis superficialis (MPS) decreased at the lowest extent – 8.3%, of m. Femorotibialis (MFT) – 16.7% (Р<0.05), and the greatest reduction occurred in m. Pectoralis profundus (MPP) – 23.4% (Р<0.001). Until the 72nd hour, the WHC of the studied muscles reached a minimum – 27.0-32.8% (Р<0.001). Consequently to the reduced WHC of muscle proteins during the first 24 hours of storage, carcasses lost 1.1–1.12%, whereas until the 72nd hour – 2.54% of their weight. The recorded weight loss during the first 4 hours after the slaughter was 38.9–43.5% of the loss during the first 24 hours; and the 24-hour loss comprised 43.1–44.5% of the total weight loss. The increased acidity and lower WHC of meat resulted in altered colour traits. During the cold storage, the L* coordinate values of all muscles studied increased, with statistically significant differences for breast muscles (Р<0.01 for MPS and Р<0.001 for MPP). The coordinates а* and b* differed substantially (Р<0.001) only for MPP meat – а* values increased by 19.1%, and b* values by 59.4%.