Krzysztof Damaziak

Effect of packaging method and cold-storage time on chicken meat quality

This study was performed to determine the effects of vacuum packaging (VP) and modified-atmosphere packaging (MAP) (CO2/N2 = 3:7) on the physicochemical properties and sensory attributes in chicken breast meat during storage at 2ºC±0.5ºC for 5, 10 and 15 days. Results showed that storage time influenced the physicochemical properties, except sensory attributes, shear force and shear energy of chicken meat. The extended storage time was causing an increase in the pH value, drip loss and in values of color parameters (L, a* b*) in chicken meat. Moreover, the packaging method affected values of drip loss, cooking loss and shear force. Fresh meat (0 days of storage) was characterized by the highest overall quality assessed with the semi-consumer scaling method. Storage time and packaging method were found to exert significant effects on the physicochemical parameters determined instrumentally and on sensory attributes of meat evaluated with the semi-consumer scaling method.

Early and 24 h post-mortem changes in breast muscle quality traits of two turkey genotypes and their reciprocal crosses raised under semi-confined conditions.

Abstract An experiment was conducted to determine the effect of reciprocal crossing of turkeys on early and 24 h post-mortem changes in quality traits of their breast muscles. The turkeys of slow-growing (SG) and fast-growing (FG) lines as well as SF (SG × FG) and FS crosses (FG × SG) were reared with access to free range. After slaughter turkey breast muscles were examined in the following terms: 5 min, 45 min, 2 h and 24 h post-mortem, for: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes of the breast meat were evaluated based on chemical composition, water holding capacity (WHC), cooking loss (%), shear force (N) and colour (L*, a*, b*). Despite differences in the rate of post-mortem changes, the genotype of turkeys had no significant effect upon many quality traits assessed 24 h post-mortem. Meat of lighter birds (SG and SF) was characterised by a lower fat content but a similar protein content compared to meat of FS and FG turkeys. In addition, meat of males from these groups was darker. Meat from the breast muscles of heavier birds (FS and FG) was harder. Significant negative maternal effects were determined for temperature of meat of both male and female turkeys, for pH2 and EC24 of males as well as for L2, L24 and cooking loss of female meat. Positive heterosis was confirmed only for pH2 of female meat and for G2 of male meat. In summary, the direction of fast- and slow-growing turkey crossing may affect the quality of their meat. However, meat of both types of hybrids reared under semi-confined conditions (with the possibility of using free range) was characterised by appropriate quality parameters.

Comparsion of production performance of two genetic groups of turkeys reared in the Semi-intensive system

Production results were compared for two groups of turkeys reared in semi-intensive system. The material included 40 primitive turkeys of the light type and 40 heavy hybrids of the Big-6 line (commercial flock). Females was raised to 14 and males to 22 weeks of life. During the rearing, body weight (g) was controlled individually and feed intake (g) was monitored in groups, in weekly intervals. Significantly higher body weight values (P ≤ 0.01) were reported in both females (8806 g) and males Big-6 (23593 g), compared to primitive turkeys (2418 g and 6589 g, respectively). Big-6 turkeys were also characterized by a faster growth rate. This group compared to primitive turkeys showed also a higher feed intake and lower FCR values. Losses control of the turkeys throughout the rearing period showed a 17.5% increase in the survival rate in the group of primitive turkeys.

Influence of indoor and outdoor systems on meat quality of slow-growing chickens

ABSTRACT The aim of this study was to determine the effect of rearing system (with and without outdoor access) on carcass composition and meat quality in slow-growing chickens. The highest shear force was found for the breast muscles of chickens from the outdoor group. Breast (P < 0.05) and leg (P < 0.01) muscles of the birds from the outdoor group were characterized by the highest content of vitamin E. Therefore, differences were observed in fatty acid composition. A lower level of saturated fatty acid (SFA) (P < 0.01), a higher level of n-3 polyunsaturated fatty acid (PUFA) (P < 0.05), and a lower n-6/n-3 PUFA ratio (P < 0.01) were found in breast and leg muscles of chickens from the outdoor group. The breast muscles of chickens from the outdoor group were characterized by a higher level of monounsaturated fatty acids (MUFA) (P < 0.01) and a lower level of n-6 PUFA (P < 0.05). The rearing system may modify the health-promoting properties of meat.

Dietary vitamin E supplementation on cholesterol, vitamin E content, and fatty acid profile in chicken muscles

Abstract: The aim of the study was to determine the effect of dietary vitamin E level on cholesterol and vitamin E content and fatty acid profile in broiler chicken breast and leg muscles. Chickens (420 cocks) were randomly divided into two feeding groups (210 birds each). The control group was fed with standard diet containing 44 mg kg-1 of vitamin E, whereas the experimental group was supplemented with extra 200 mg kg-1 of vitamin E. The dietary addition of vitamin E caused a significant increase in its content in the muscles, with a higher value noted in the leg muscles. Meat of chickens fed with the higher dose of vitamin E was also characterized by a lower cholesterol level. The addition of vitamin E as well as type of the muscles had a significant effect on the fatty acid profile and values of atherogenicity (AI) and thrombogenicity (TI) indices. The recorded increase in the content of n-3 polyunsaturated fatty acids (PUFAs) and a decrease in the n-6/n-3 fatty acid ratio indicate a positive effect of vitamin E on the fatty acid profile. In turn, lower values of AI and TI in leg muscles of chickens with a high intake of vitamin E prove the beneficial fatty acid profile in these muscles upon such supplementation.

Variation in Growth Performance and Carcass Yield of Pure and Reciprocal Crossbred Turkeys

Abstract This study compared growth, feed conversion ratio (FCR), mortality rate and results of slaughter analysis of slow-growing Bronze turkeys (SG), fast-growing Big 6 turkeys (FG), and their reciprocal crosses (SF and FS). Until 6 weeks of age the birds were kept indoors and afterwards they were allowed to use free ranges. Toms were reared until 21 and hens until 15 weeks of age. The FS turkeys were characterized by higher (P≤0.05) BW and dressing percentage and by lower FCR compared to the SF crosses of both sexes. The analysis of orthogonal contrasts demonstrated that values of most of the slaughter analysis parameters were due to the additive effect of genes. Only weight of skin with fat and of gizzard could result from heterosis. Study results demonstrate that FS crosses constitute better material for the alternative production of turkeys compared to the other analysed groups (SG, SF, FG).

Effect of dietary canthaxanthin and iodine on the production performance and egg quality of laying hens

In this study, we aimed to evaluate the effect of canthaxanthin (CX) and iodine (I) on the production of laying hens, on counteracting debilitation of the vitelline membrane, and on inhibiting Salmonella growth in eggs stored at 30°C. Three hundred hens were reared in cages. Birds were divided into six feeding groups (10 hens × 5 repetitions) that were administered 0, 3 or 6xa0ppm of CX and 1 or 10xa0ppm of I with their diets. Laying rate, egg weights, and feed conversion ratios were controlled. The quality of fresh eggs was assessed in wks 25-26, 48-50 and 62-63 of hens lives. An additional batch of eggs was incubated at the temperature of 30°C, and egg quality changes were monitored on days 3, 6 and 9 of storage. Additionally, eggs collected from four experimental groups of hens whose diets had been iodated with 1 or 10xa0ppm of I and supplemented with 0 or 6xa0ppm of CX were infected under laboratory conditions with Salmonella, and incubated for 5 and 10 d. The laying rate, egg weights, and feed conversion ratio were significantly improved. Dietary inclusion of CX contributed to a higher resistance of the vitelline membrane of egg yolks, but only for fresh eggs. Vitelline membrane degradation during egg storage at 30°C was significantly counteracted by dietary inclusion of I at a dose of 10xa0ppm. The same I dose resulted in the complete inhibition of Salmonella growth until day 10 of incubation, but exclusively for eggs collected from 40-week-old hens. Dietary supplementation with 10xa0ppm of I was found to impart high level of resistance to the vitelline membrane against the growth of Salmonella in case of eggs stored at 30°C; therefore, I was found to be more beneficial by ensuring longer preservation than that of CX. However, dietary supplementation with CX was found to increase the resistance of vitelline membrane in fresh eggs.

Early and 24 h post-mortem thigh (ilio tibialis) muscle metabolism and meat quality in two genetic types of turkeys and their reciprocal crosses, raised under semi-confined conditions

ABSTRACT 1. The experiment was conducted in order to determine the effect of the direction of turkey crossing on quality traits of their thigh muscle. 2. In total, 1358 turkeys of slow- (SG) and fast-growing (FG) lines as well as SF crosses (SG × FG) and FS crosses (FG × SG) were reared with access to free range to 21 weeks of age in the case of males and 15 weeks of age in the case of hens. 3. After slaughter of 15 males and 15 hens from each genetic line, their thigh muscles were examined and the following traits were measured after 5-min, 45-min, 2-h and 24-h post-mortem: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes were evaluated based on chemical composition, water holding capacity, cooking loss (%) and colour. 4. The rate of post-mortem changes in temperature, G, L and pH in muscles differed among the 4 lines of turkeys, with the highest metabolic rate determined for muscles of SG turkeys, followed by muscles of SF, FS and FG birds. A more beneficial muscle water holding capacity of both sexes of turkeys and better results of cooking loss in male muscles were found in SG and SF turkeys. The thigh muscles of the crosses were characterised by a higher content of protein and a lower content of fat compared to the muscles of FG turkeys, and in the case of the males also by a higher protein content compared to the muscles of SG birds. 5. Owing to the faster post-mortem metabolism, better water holding capacity, lower cooking loss and fat content at a similar content of protein, the thigh muscles of SF crosses raised in the free range system represent a better quality of meat for consumers compared to the thigh muscles of FS turkeys.

Analysis of storage possibility of raw and smoked breast meat of oat-fattened White Kołuda® goose based on their quality characteristics

Raw and smoked (spickgans) fillets of oat-fattened White Kołuda® goose were packed in: PET - ethylene terephthalate bags; VSP - 99% vacuum; MAP1 - 80% O2, 20% CO2; MAP2 - 70% N2, 30% O2; MAP3 - 30% O2, 40% N2, 30% CO2, and stored at a temperature of 2°C. On the day of packaging (0 d) and during storage of raw (5, 7, 10 d) and smoked fillets (5, 10, 15 d), the samples were analyzed for weight losses, physicochemical traits, and chemical composition. The study demonstrated the effect of storage time and packaging method on storage yield of raw and smoked fillets. In VSP, the raw fillets were characterized by the lowest amount of leakage, whereas spickgans were characterized by the highest storage yield and weight loss. The analysis of the effect of the modified atmosphere demonstrated the lowest weight loss of raw fillets at, simultaneously, the smallest amount of leakage in MAP1. The spickgans stored in MAP2 showed higher weight, higher yield after storage, and lower storage loss in all terms of analyses compared to MAP1 and MAP3. The greatest cooking loss at simultaneously the lowest pH values was determined for the samples stored in VSP. The WBSF values of raw fillets were decreasing along with storage time, in contrast to WBSF values of spickgans, in which case the value of this parameter increased compared to 0 d. Raw fillets stored in MAP1 and MAP3 were characterized by the most significant increase in the value of L*, by a decrease in the value of a* and an increase in that of b* parameter. Visual assessment of spickgans on 15 d of storage revealed the presence of white sediment on the surface of products, except for the samples stored in VSP. The study demonstrated the effect of storage time on the contents of protein and fat in raw fillets and on the contents of salt and fat in spickgans.

Sigmoid Models for the Growth Curves in Medium-Growing Meat Type Chickens, Raised under Semi-Confined Conditions

Abstract The study analyzed the growth of medium-growing chickens of the CCGP experimental line, using Gompertz, Logistic, and Richards models as well as body gain curves. The birds were reared until 9 wk of age. To fit BW values to the applied models, determination coefficients (R2 ,Ř2) and standard error of the mean (±SE) were calculated for 487 male and 493 female chickens. The comparison of results obtained demonstrated the Gompertz model to be the most precise equation to describe the growth of both sexes of CCGP chickens, though in all examined models the determination coefficients were approximating 99%. According to the Gompertz model, the chickens may reach the maximum BW at the age of 16 wk (5900 g - males and 4000 g - females), whereas the maximum daily BW gain - on day 47 (69.0 g) in males and on day 41 (50.0 g) in females. Values achieved in the Logistic model were the most diverging from the values obtained with other models, whereas the Richards model may be successfully applied to estimate BW of chickens. Females were reaching the maximum BW gains earlier, but the curve of their BW gain was proceeding with two peaks (at ca. 4 wk - 313.09 g/wk and at 6 wk - 327.59 g/wk), which was probably due to partial growth deceleration as a result of allowing the birds to use free ranges on day 14. In the case of males, the maximum BW gain (727.35 g/wk) was reached at 6.2 wk.