Comparison of physical and qualitative traits of meat of two Polish conservative flocks of ducks

Abstract

In two Polish conservative flocks of Miniduck (K2) and Pekin (P33), registered by FAO as domestic genetic resources (World Watch List, 2000) the mean values of physical (tissue components) and qualitative traits of meat (pH 15 , pH 24 , colour of meat) were determined. The experimental flocks showed significant variations in body weight at 7 weeks of age (1540 vs 2088 in drakes and 1395 vs 1986 g in ducks), in the proportion of breast and leg muscles and skin with subcutaneous fat in eviscerated carcass. K2 ducks are characterized by outstanding musculature of breast and P33 ducks by that of lower leg and by low fatness. pH 15 values of breast and leg muscles in K2 and P33 birds were greater than pH 24 of these muscles. In both flocks pH 15 values of 6.09 to 6.33 and pH 24 values of 5.90 to 6.05 in breast muscles were lower than in leg muscles (6.33 to 6.46 and 6.12 to 6.37, respectively). A significantly lower L* value (darker colour) of breast muscle was characteristic of K2 birds (43.7 in males and 40.5 in females) compared to P33 males and females. Furthermore, breast muscles of K2 drakes and ducks had significantly higher redness (a*) and yellowness values (b*) than P33. In pectoralis superficialis muscle of K2 and P33 females, a significantly lower diameter was found for white muscle fibres (αW) (30.0 to 30.5 µm) and for red muscle fibres (βR) (16.9 to 17.6 µm) than in biceps femoris muscle (αW from 48.3 to 54.2; βR from 36.0 to 37.1 µm). Muscle fibres of K2 compared to P33 ducks were characterized by significantly greater diameters of βR muscle fibre in pectoralis superficialis muscle, and by lower αW and βR fibre diameters in biceps femoris muscle. The experiment showed that meat of ducks from the conservative flocks studied is valuable from the consumer's point of view.

Influence of housing system on the growth and histological structure of duck muscles

“…There were no statistically significant differences in percentages of particular fibres associated with the housing system of the ducks (Tables 5 and 7). According to Kisiel & Książkiewicz (2004) and Witkiewicz et al (2004), it is a genetic trait that is typical of the waterfowls. In turn, the statistical analysis confirmed the significant (P <0.05) effect of the housing system on diameter of both large and small muscle fibres in the case of pectoralis superficialis and biceps femoris of MR71 drakes, which was higher in birds from the OS group (Table 5).…”

Changes in selected physicochemical parameters of breast muscles of geese from Polish conservation flocks depending on duration of the post slaughter period

“…In ducks such measurements were carried out within the first 15 min (KNUST et al, 1995;SKRABKA-BŁOTNICKA et al, 2003), 20 min (BAÉZA et al, 1997 and even 45 min (ALEXIEVA et al, 1998) after slaughter. As regards pH 2 , all of the above mentioned authors agreed as well as by KISIEL and KSIĄŻKIEWICZ (2004) to measure it at 24 h post slaughter. This is the reason why we conducted an investigation on this topic.…”

“…From the point of view of breeding maintaining genetically diversified conservative flocks of birds is necessary to give rise to genetic variation in the selected populations (KSIĄŻKIEWICZ, 2003). These conservative flocks were used in the development of new breeding and experimental strains and synthetic lines as well as in the search for heterosis effects in commercial sets (KISIEL and KSIĄŻKIEWICZ, 2004;WAWRO et al, 2004;WOŁOSZYN et al, 2006). The world's genetic resources conservation programme currently includes 11 Polish goose populations maintained in Poland, including Suwałki geese -Su, Kartuzy geese -Ka, Kielce geese -Ki and Subcarpathian geeseSb (http://bioroznorodnosc.izoo.krakow.pl/gesi).…”

Tissue composition of carcass, meat quality and fatty acid content of ducks of a commercial breeding line at different age

“…However, POWELL (1992) stated that the intensive selection may result in worsening of nutrition value of meat. Scientific research, which were carried out on meat ducks, mainly focused on dressing percentage (PINGEL and TRETTNER, 1987;BOCHNO et al, 1992;KISIEL, 2001;KOKOSZYŃSKI et al, 2002;KISIEL and KSIĄŻKIEWICZ, 2004;KOKOSZYŃSKI and KORYTKOWSKA, 2005), chemical composition of muscles (BONS et al, 1998;WITKIEWICZ, 2000;MAZANOWSKI and KSIĄŻKIEWICZ, 2004;ADAMSKI, 2005), physical and chemical meat characteristics -pH, water holding capacity and colour (KISIEL, 2001;KISIEL and KSIĄŻKIEWICZ, 2004;ADAMSKI, 2005;ADAMSKI et al, 2005). Moreover, one of the indicators specifying meat quality is the content of unsaturated (mono-and polyunsaturated) and saturated fatty acids (BERNACKI and ADAMSKI, 2001;KOKOSZYŃSKI et al, 2002;WITKIEWICZ and KONTECKA, 2002).…”