Effect of Variety and Sex on the Carcass and Meat Quality Traits of Guinea Fowl (Numida meleagris L.).

The aim of this study was to evaluate selected parameters of carcass and meat quality in 16-week-old pearl gray and lavender guinea fowl. The birds were raised in summer and fall, in an extensive system. Until 4 weeks of age, the birds were kept indoors, and from week 5 until slaughter they could use outdoor space enclosed by a fence, adjacent to the building. Guinea fowl were fed complete chicken diets: starter (weeks 0−6), grower (weeks 7−12), and finisher (weeks >13). In comparison with lavender guinea fowl, pearl gray birds had higher live weight at slaughter (p = 0.001) and higher carcass weight (p = 0.001). Females, compared with males, had a higher carcass dressing percentage (p ˂ 0.001), lower liver weight (p = 0.008), lower heart weight (p ˂ 0.001), and lower total weight of giblets (p = 0.004). The leg muscles of pearl gray guinea fowl, compared with those of lavender birds, had a higher content of dry matter (p ≤ 0.029). The breast muscles (p ˂ 0.001) and leg muscles (p = 0.017) of lavender guinea fowl contained less fat than the muscles of pearl gray birds. The breast muscles of females had a higher content of dry matter (p = 0.044) and ash (p = 0.016), and lower total collagen content (p = 0.028) than the breast muscles of males. The leg muscles of females were characterized by a higher pH (p ˂ 0.001), and lower cooking loss (p = 0.004) and drip loss (p = 0.005) than the breast muscles of males. The breast muscles of lavender guinea fowl, compared with those of pearl gray birds, were characterized by a higher chroma value (p ˂ 0.001), and a higher contribution of redness (p ˂ 0.001) and yellowness (p = 0.002), and their leg muscles were lighter in color (p ˂ 0.001), with a higher contribution of yellowness (p = 0.041) and a higher hue angle (p = 0.037). The value of chroma (p = 0.004) and the contribution of yellowness (p = 0.002) were higher in the breast muscles of females, compared with males. Neither variety nor sex affected (p > 0.05) the evaluated sensory properties of guinea fowl meat or the proportions of total SFAs, total UFAs, total MUFAs, and total PUFAs in the intramuscular fat (IMF) of breast and leg muscles. Meat from guinea fowl of both analyzed varieties can be an excellent alternative to more popular types of poultry meat due to its high nutritional value and eating quality.

Chemical Composition and Fatty Acid Profile of the Pectoralis major Muscle in Broiler Chickens Fed Diets with Full-Fat Black Soldier Fly (Hermetia illucens) Larvae Meal.

The aim of this study was to determine the effect of full-fat Hermetia illucens (HI) larvae meal used as a substitute for 50%, 75% and 100% of soybean meal (SBM) in diets fed to male Ross 308 broiler chickens on the proximate chemical composition and fatty acid profile of the Pectoralis major (PM) muscle. The muscles of chickens fed HI larvae meal were characterized by a higher (p < 0.05) total concentration of pigments and lower (p < 0.05) ash content. At the lowest dietary inclusion rate (50%) of HI larvae meal, the PM muscle had a lower (p < 0.05) content of fat and collagen, compared with the remaining treatments. An analysis of the fatty acid profile of the PM muscle revealed that the total concentrations of saturated fatty acids increased (p < 0.05) and the total concentrations of polyunsaturated fatty acids decreased (p < 0.05) with increasing inclusion levels of HI larvae meal. The changes in the fatty acid profile of muscles in birds receiving HI larvae meal led to a decrease in the nutritional value of fat. The present findings indicate that the ≥50% inclusion rate of full-fat HI larvae meal as a protein source alternative to SBM in broiler chicken diets is too high due to its negative effect on the fatty acid profile of meat.

The Fatty Acid Profile of Meat from New Zealand White Rabbits Raised under Intensive and Extensive Production Systems.

The aim of this study was to compare the fatty acid (FA) profile of meat from New Zealand White rabbits raised from 30 to 90 days of age under intensive (IPS) and extensive (EPS) production systems. In group IPS, the rabbits were housed in wire mesh cages with a slatted floor (16.7 animals/m2) and were fed a commercial pelleted diet. In group EPS, the rabbits were housed in free-standing cages on straw litter (2.5 animals/m2) and were fed a conventional farm-made diet (green fodder, barley grain, stale bread, hay). The FA profile of intramuscular fat (IMF) was analyzed in samples of Longissimus thoracis et lumborum (LTL) muscle. The analyzed production systems had no significant effect on the content of most FAs in IMF. However, the differences between group means contributed to more desirable values of the quality indicators of IMF (in particular in the LTL muscle) in group IPS. The study demonstrated that the claim that meat produced under less intensive farming systems is of superior quality could be an oversimplified generalization that should be validated in research.

Changes in the quality of meat (Longissimus thoracis et lumborum) from Kamieniec lambs during long-term freezer storage.

The aim of this study was to determine changes in the quality of lamb meat (Longissimus thoracis et lumborum), which was vacuum-packaged and freezer-stored (-26°C) for 6 and 12 months. The experiment was performed on 12 male lambs of the Kamieniec Longwool breed, raised to 106 days of age. In comparison with fresh meat, thawed meat was characterized by lower ash content, higher pH, greater natural drip loss and cooking loss, and lower scores for taste intensity. Vacuum packaging and low-temperature storage protected lamb meat against oxidative changes, and alleviated the adverse effects of oxidation on the color, aroma and taste of meat. It can be concluded that freezer storage (-26°C) of vacuum-packaged meat can help meet consumer demand for lamb meat products in periods when fresh meat is unavailable. However, it should be noted that long-term frozen storage induces undesirable changes in meat quality, including a decrease in water-holding capacity and taste intensity.