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The objectives of this work was to study the effect of sex and weight at slaughter on meat quality in the longissimus muscle of Black goat and Meriz goat .Twenty four weaned kids from each breed were divided equally and penned individually into two groups .The 1st was castrated using rubber ring ,and the 2nd was left intact ,and was assigned to be slaughtered at 15,20 and 25 kg live body weight .The overall means of  pH, lightness ,redness ,yellowness, drip loss, cooking loss and tenderness were 5.94±0.009 , 46±1.16 , 20.01±0.68 , 35.68±0.78 ,0.25±0.01, 12.17±0.35 ,1.65 ±0.008, respectively. Results revealed neither breed nor sex had a significant effect (p>0.05) on pH, color, drip loss, cooking loss and tenderness. It seems that kids slaughtered at 15 kg had more lightness, have more drip loss, and lower cooking loss as compared with kids slaughtered at 20 and 25 kg.

In the present study, 25 cuts of shank form adult cattle coming from the same slaughtering batch, were withdrawn just after manual sectioning/deboning, and each divided into two pieces (Prox and Dist) of approximately the same weight, that were vacuum packaged by using two different packaging systems: vacuum chamber machine with a bag material and a thermoforming packaging machine with top and bottom webs named BAG and THF respectively. The packed cuts were stored at 2-3°C for 20 days. The drip loss was calculated at the end of the storage as the difference between drained weight and net. Internal muscle pH and pH of the exudate present in the package and microbiological analyses (by pooling the samples) were performed at T0 and at the end of the storage. The drip loss, was significantly lower with BAG packaging: this difference was evident after 20 days of storage (average ± STD BAG vs THF = 1.04±0.36% vs 1.71±0.42%; P<0.01). The values were, in general, low for both the packaging systems, never above 2%. Moreover, shrink bag packages are characterized by better overall pack appearance and less plastic weight per pack. Forming step reduce the thickness of thermoforming material lowering the mechanical resistance and the barrier to oxygen, on the contrary after shrinking bag materials are thickened. The pH of muscles was stable, although a slight increase was evidenced after 20 (average ± STD BAG vs THF= 5.73±0.05 vs 5.78±0.09; P<0.01), due to the ageing of meat. The pH of the exudate was equal at T20 (average ± STD BAG vs THF = 5.34±0.20 vs 5.33±0.17). The drip loss didn’t influence the development of all the microflora; in particular LAB, that represented the main microbial population, showed a gradual increase from T0 (2.20±0.41 Log CFU/g) to T20 (average ± STD BAG vs THF= 4.76±0.29 Log CFU/g vs 4.75±0.0.15 Log CFU/g). Enterobacteriaceae showed an increase, if compared to the initial counts, due to the prolonged storage and the gradual growth of ephemeral microorganisms, without differences among the two series (Enterobacteriaceae: T0=<1.7 Log CFU/g to T20 average ± STD BAG vs THF = 2.83±0.77 Log CFU/g vs 3.09±0.0.70 Log CFU/g). In conclusion, the use of the BAG system demonstrated to have an effect in reducing the drip loss of beef cuts during the refrigerated storage, with only slight influence on the other characteristics of raw meat.

Broiler production at mass level has already been achieved and now emphasis is being laid on increasing meat quality by altering various characteristics of broiler meat. Appearance, texture, juiciness, wateriness, firmness, tenderness, odor and flavor are the most important and perceptible meat features that influence the initial and final quality judgment by consumers before and after purchasing a meat product. The quantifiable properties of meat such as water holding capacity, shear force, drip loss, cook loss, pH, shelf life, collagen content, protein solubility, cohesiveness, and fat binding capacity are indispensable for processors involved in the manufacture of value added meat products. Nutrition of birds has a significant impact on poultry meat quality and safety. It is well known that dietary fatty acid profiles are reflected in tissue fatty acid. Management of poultry meat production is reflected mostly on consumption features (juiciness, tenderness, flavour) of meat. After slaughter, biochemical changes, causing the conversion of muscle to meat, determine final meat quality. Postmortem carcass temperature has profound effect on rigor mortis and the physicochemical changes observed in PSE muscles are attributed to postmortem glycolysis, temperature, and pH. Primary processing and further processing have become a matter of concern with respect to nutritional quality of broiler meat. Genetic variation among birds could contribute to large differences in the rate of rigor mortis completion and meat quality. Heritability estimates for meat quality traits in broilers are amazingly high (0.35–0.81), making genetic selection a best tool for improvement of broiler meat quality.

In this review, recent findings related to various factors influencing quality properties of fish meat and its products during frozen storage are introduced. Many studies have indicated that protein denaturation is the factor determining the quality of frozen fish meat. Ice crystal size does not necessarily determine the quality of frozen fish meat because the tissue of meat reabsorbs water during the thawing process, unless it has been previously damaged by protein denaturation. However, the effects of ice crystals on the quality of thawed fish meat differ based on the fish species, post-mortem stages, protein denaturation, and processing conditions of the fish meat. In the case of frozen-thawed lightly salted fish meat, salting conditions greatly affect the water holding capacity of muscle and the ice crystal size. Also, in the case of frozen kamaboko, which is denatured protein gel, as the thawed water is not absorbed enough by the protein gel, ice crystal size could be a determining factor of quality. The appropriate freezing and storage conditions required for maintaining quality must be based upon the characteristics of each seafood product.

The paper presents the results of a study on the relationship between acidification (pH) and standard quality characteristics of the meat of Polish Large White × Polish Landrace pig crossbreds. The meat for the study was obtained from 184 F1 Polish Large White × Polish Landrace fatteners from a herd free of the stress-sensitivity gene. The obtained results were analysed in groups formed according to the meat’s measured pH45 values (≤ 6.3; 6.3–6.7; > 6.7) and pHu values (≤ 5.3; 5.3–5.6; > 5.6). Increasing measured pH45 values were paralleled by greater water-holding capacity and plasticity, lower drip loss, darker colour L* as assessed visually and with equipment, and greater content of muscle pigments (P < 0.01) of the evaluated meat. Higher pHu values had a more pronounced impact on WHC, free drip loss, tenderness, water content, and colour parameters: a*, b*, chroma C* (P < 0.01), and hue angle ho (P < 0.05). The obtained simple correlations between pH45 and pHu acidity and meat-quality characteristics indicate that the measured pH45 value was correlated more closely than ultimate acidification (P < 0.01) with visually assessed colour intensity, tactilely assessed meat hardness, colour lightness L* (P < 0.01), hue angle ho (P < 0.05), and muscle pigment content. On the other hand, pHu was more strongly correlated with water-holding capacity, drip loss, meat tenderness as well as water and protein content (P < 0.01).

The present research studied for the first time the potential application of the fat derived from the black soldier fly larvae fat (BSLF) in substitution to the soybean oil in the diet for broiler chickens: growth performances, feed-choice, blood traits, carcass characteristics and meat quality were considered in this study. A total of 150 male broiler chicks (Ross 308) at one-day of age were randomly allotted to 3 dietary treatments (5 replicates and 10 birds/pen): a basal control diet (C group), and the same diet in which the soybean oil was replaced by 50% (CH group) or 100% (H group) BSLF. Growth performances, feed-choice test, blood traits and slaughtering performances were not influenced by diets. Independently of BSLF inclusion, broiler chickens breast meat had also similar crude protein and ether extract contents and displayed similar thawing loss. Furthermore, pH, L*, a*, b* colour values, and drip loss were unaffected by dietary treatments both at 0 and 9 days of refrigerated storage. As expected, the fatty acid profile of broiler chickens breast was greatly affected by BSLF inclusion level. With increasing BSLF inclusion rate, the proportion of SFA increased (32.2, 37.8, 43.5% for C, CH and H breast meat, respectively, p < .001) to the detriment of the PUFA fraction (22.7, 23.0, 22.9% for C, CH and H breast meat, respectively, p < .001). On the contrary, MUFA fraction was unaffected. BSLF inclusion guaranteed satisfactory productive performances, carcass traits and overall meat quality, thus suggesting that BSLF could be a promising new feed ingredient for chickens.

One of the consequences of intense genetic selection for growth of poultry is the recent appearance of abnormalities in chicken breast muscles, such as white striping (characterised by superficial white striations) and wooden breast (characterised by pale and bulged areas with substantial hardness). The aim of this study was to evaluate the quality traits of chicken fillets affected by white striping and wooden breast abnormalities. In two replications, 192 fillets were divided into the following four classes: normal (n=48; absence of any visual defects), white striping (n=48, presence of white striations), wooden breast (n=48; diffusely presence of hardened areas) and white striping/wooden breast (n=48; fillets affected by both abnormalities). Morphology, raw meat texture and technological properties were assessed in both unprocessed (pH, colour, drip loss, cooking loss and cooked meat shear force) and marinated meat (marinade uptake, purge loss, cooking loss and cooked meat shear force). Fillets affected by white striping, wooden breast or both abnormalities exhibited higher breast weights compared with normal fillets (305.5, 298.7, 318.3 and 244.7 g, respectively; P<0.001). Wooden breast, either alone or in combination with white striping, was associated with a significant (P<0.001) increase of fillet thickness in the caudal area and raw meat hardness compared with both normal and the white striping abnormality, for which there was no difference. Overall, the occurrence of the individual and combined white striping and wooden breast abnormalities resulted in substantial reduction in the quality of breast meat, although these abnormalities are associated with distinct characteristics. Wooden breast fillets showed lower marinade uptake and higher cooking losses than white-striped fillets for both unprocessed and marinated meats. On the other hand, white-striped fillets showed a moderate decline in marinade and cooking yield. Fillets affected by both abnormalities had the highest (P<0.001) ultimate pH values. In contrast, the effects on colour of raw and cooked meat, drip loss, purge loss and cooked meat shear force were negligible or relatively low and of little practical importance. Thus, the presence of white striping and wooden breast abnormalities impair not only breast meat appearance but also the quality of both raw and marinated meats mainly by reducing water holding/binding abilities.

Reducing the dietary CP content is an efficient way to limit nitrogen excretion in broilers but, as reported in the literature, it often reduces performance, probably because of an inadequate provision in amino acids (AA). The aim of this study was to investigate the effect of decreasing the CP content in the diet on animal performance, meat quality and nitrogen utilization in growing-finishing broilers using an optimized dietary AA profile based on the ideal protein concept. Two experiments (1 and 2) were performed using 1-day-old PM3 Ross male broilers (1520 and 912 for experiments 1 and 2, respectively) using the minimum AA:Lys ratios proposed by Mack et al. with modifications for Thr and Arg. The digestible Thr (dThr): dLys ratio was increased from 63% to 68% and the dArg:dLys ratio was decreased from 112% to 108%. In experiment 1, the reduction of dietary CP from 19% to 15% (five treatments) did not alter feed intake or BW, but the feed conversion ratio was increased for the 16% and 15% CP diets (+2.4% and +3.6%, respectively), while in experiment 2 (three treatments: 19%, 17.5% and 16% CP) there was no effect of dietary CP on performance. In both experiments, dietary CP content did not affect breast meat yield. However, abdominal fat content (expressed as a percentage of BW) was increased by the decrease in CP content (up to +0.5 and +0.2 percentage point, in experiments 1 and 2, respectively). In experiment 2, meat quality traits responded to dietary CP content with a higher ultimate pH and lower lightness and drip loss values for the low CP diets. Nitrogen retention efficiency increased when reducing CP content in both experiments (+3.5 points/CP percentage point). The main consequence of this higher efficiency was a decrease in nitrogen excretion (−2.5 g N/kg BW gain) and volatilization (expressed as a percentage of excretion: −5 points/CP percentage point). In conclusion, this study demonstrates that with an adapted AA profile, it is possible to reduce dietary CP content to at least 17% in growing-finishing male broilers, without altering animal performance and meat quality. Such a feeding strategy could therefore help improving the sustainability of broiler production as it is an efficient way to reduce environmental burden associated with nitrogen excretion.

The aim of this study was to evaluate the effect of the packaging system type on the physical characteristics and microbial changes in ostrich meat during refrigerated storage. The applied packaging systems were vacuum packaging (VP) and modified atmosphere packaging (MAP) using two combinations of gases: MAP1 (40% O2/40% CO2/20% N2) and MAP2 (60% O2/30% CO2/10% N2). Eight meat samples were obtained in three replicates for all parameters, except for pH, for which six replicates were obtained from the M. ilifibularis (IF) muscle, and were stored in a refrigerator at 2 °C and analyzed at 0, 4, 8, 12 and 16 days for the effect of packaging methods on physical meat quality. The initial pH (5.99) decreased at the end of the storage time for MAP1 to 5.81, whereas VP was stable from day 0 to 12 and increased up to 6.08 on day 16. Regarding meat color, the L* value increased during storage for MAP1 and MAP2 from 36.99 to 40.75 and 41.60, respectively, whereas it declined for VP to 34.22. The same tendencies were reported for redness (a*) and yellowness (b*). Drip loss was the lowest in MAP1 and highest in VP. The lowest total viable bacteria counts were identified in VP, as compared to MAP1 and MAP2.

The dietary energy level can affect ruminal microbiota, and further can affect rumen fermentation and fatty acid (FA) synthesis. In this study, we investigated the correlations between rumen bacteria and rumen fermentation parameters and intramuscular fat (IMF) FA profiles of Holstein bulls fed different energy diets via using 16S rRNA high-throughput sequencing and gas chromatography. The results showed that the improved dietary energy increased propionate, isobutyrate and isovalerate concentrations, and decreased acetate concentration and the acetate/propionate ratio. Increased dietary energy improved beef IMF content and had no effects on cooking loss, Warner-Bratzler shear force, water holding capacity, or drip loss. Increase dietary energy also decreased C18:0, C18:1 trans , C22:0, C20:3n-3, C22:6n-3, and saturated fatty acids, and increased C18:1 cis -9, C18:2n-6 trans , and monounsaturated fatty acids. 16S rRNA high-throughput sequencing analysis revealed that dietary energy had no impact on alpha diversity or the relative abundance of most of the major phyla and genera in rumen. In all dietary treatment groups, the dominant microbial phyla were Bacteroidetes (54.91%) and Firmicutes (33.60%), and the major microbial genus was Prevotella_1 (21.75%). Improved dietary energy decreased the abundances of Firmicutes and Tenericutes and increased that of Proteobacteria at the phylum level, while decreasing those of RC9_gut_group , and increased Prevotellaceae_UCG-004 , Phocaeicola , Acetitomaculum , Lachnoclostridium_1 , Prevotellaceae_UCG-003 , and Anaerovibrio at the genus level. Spearman correlation analysis showed high correlations between rumen bacteria and fermentation parameters/IMF FA profiles. Collectively, our data indicated that dietary energy affects the ruminal microbiota, and further affects ruminal fermentation and IMF FA composition.