Effect of cold storage terms on physico-chemical characteristics of Japanese quail - Coturnix coturnix japonica meat

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% - Р0.05, and the greatest reduction occurred in m. Pectoralis profundus MPP – 23.4% Р0.001. Until the 72nd hour, the WHC of the studied muscles reached a minimum – 27.0-32.8% Р0.001. 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 Р0.01 for MPS and Р0.001 for MPP. The coordinates а* and b* differed substantially Р0.001 only for MPP meat – а* values increased by 19.1%, and b* values by 59.4%.