EFFECT OF BREED ON MEAT QUALITY IN JAPANESE QUAILS (COTURNIX COTURNIX JAPONICA)

Trakia Journal of Sciences, No, pp181-188, 013 Copyright 013 Trakia University Available online at: http://www.uni-sz.bg ISSN 1313-7050 (print) ISSN 1313-3551 (online) Original Contribution EFFECT OF BREED ON MEAT QUALITY IN JAPANESE QUAILS (COTURNIX COTURNIX JAPONICA) S. Ribarski 1*, A. Genchev 1 Department of Meat and Meat Products, Faculty of Agriculture, Trakia University, Stara Zagora Bulgaria, Department of Poultry Science, Faculty of Agriculture, Trakia University, Stara Zagora, Bulgaria ABSTRACT At present, Japanese quails are reared in many countries in Asia, Europe, the Middle East and America for eggs and meat production. In the USA and Europe, producers are oriented to breeds with superior meat traits. In our country, two Japanese quail breeds are generally preferred for industrial scale production the meat type Pharaoh and the all-purpose Manchurian Golden breeds. The purpose of the present study was to establish the effect of quail breed on the quality of produced meat. The two groups of quails were slaughtered at 35 days of age after 4-hour fasting period. The physicochemical properties of meat (рн, muscle colour on the CIE L*a*b* system and water holding capacity) from two breast muscles - m. Pectoralis superficialis (MPS) and m. Pectoralis profundus (MPP) were investigated. In both breeds, ph values of studied breast muscles were similar, suggesting that glycogen depots in breast muscles and the post mortem anaerobic glycolysis rate were almost comparable. The absolute reduction of ph values ( рн abs ) was less pronounced in Pharaoh quails, while the breast meat of this breed had better water holding capacity (WHC). The analysis of meat colour traits showed similar values of L* in both breeds. The а * and b* values were higher in MPS (Р<0.001) than in MPP. During meat storage, a* values increased until the 4 th hour, especially in MPP (Р<0.05). A similar trend was present for b* values, but differences were not statistically significant. The data for colour coordinates L*, a* and b* allowed for determination of the colour difference ( Е*), which was considerable for MPP (Р<0.05). At the background of lower a* and b* values of Pharaoh quail meat, observed chroma values (С*) were also lower. During storage, C* values increased, with more pronounced differences for MPP (Р<0.01). The Hue angle (h o ) did not change significantly during that time, despite the slight tendency towards reduction of values. Key words: Japanese quails, meat quality, рн, water holding capacity, colour coordinates, L*, a*, b*, C*, Hue o. INTRODUCTION During the last decade, the global consumption of poultry meat has increased. Compared to beef, pork and mutton, poultry meat is defined as leaner. It is rich in polyunsaturated fatty acids (PUFA), and low sodium and cholesterol content. Poultry meat is a suitable source for *Correspondence to: Stefan Ribarski, Department of Meat and Meat products, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria, ribarski@uni-sz.bg 181 Trakia Journal of Sciences, Vol. 11,, 013 production of the so-called "functional foods". It contains bioactive substances with beneficial effects for human health conjugated linoleic acid, vitamins, antioxidants, Ω 6 and Ω 3 PUFA (1, ). Along with increased chicken and turkey meat production, there is also an increased interest towards the production and consumption of meat from pheasants, partridges, Japanese quails and other non-commercial bird species, reared under industrial conditions. Today, Japanese quails are reared in many countries in Asia, Europe, the Middle East and America both for eggs and meat production.

Manually deboned Japanese quail meat contains 7.5 75.1% water, 0-3.4% protein, 1.0 3.4% lipids and 1. 1.6% mineral substances (3, 4). Mechanically deboned quail meat contains 17% protein, 10% fat and.6% minerals. The proportion of bone does not exceed 0.75%, with average diameter of about 0.05 mm (5). Comparative studies on physicochemical properties of meat from quails, broiler chicken and ducks demonstrated that quails had the lowest-calorie meat with highest protein content (6). The ph of meat is one of the most important traits for poultry meat quality. It is established that this trait changes most dramatically during the first hours after the slaughter. This is a period of most enhanced glycolysis and lactate accumulation into the muscle tissue. The rate of these processes and the lowering of skeletal muscle ph in the early post slaughter period are essential for meat quality. In a study on the time course of changes in ph of m. Pectoralis superficialis in broiler chickens, breast muscle glycolysis was complete until the 45 th min post mortem, and afterwards average ph remained almost unchanged (7). One investigation on physicochemical properties of goose meat concluded that during the first 45 min after slaughter, ph decreased by 1.1 and 7.1%, whereas over 4 hours, the decrease was by 9.7-19.3% (8). A similar dynamics of ph reduction was exhibited by Japanese quail meat by 7.5-11% on the average (4). Reduction of ph alters the spatial structure of myofibrillar proteins, which results in lower water holding capacity (WHC) of meat. The extent of myosin shrinkage depends on the rate of glycolysis and ultimate ph values, as well as on the rate of post mortem temperature decrease. These events are most intensive during the first 4 hours after the death (4). An investigation of physicochemical properties of poultry meat demonstrates that ph of chicken meat is very low, hence it s WHC. This increased the drip loss during storage and the cooking loss (9) in a study on the effect of breed on quail meat quality and composition, the meat of the English White breed has proved to be with lower fat content and better WHC compared to the Pharaoh (10). The research on the effect of slaughter age on slaughter traits and chemical composition of meat showed that 35 days of age was the optimal slaughter age for Pharaoh (meat type) and Manchurian Golden (heavy all-purpose type) quail breeds (11, 1). For egg-type breeds, this age is about 4 days, when live weight of birds attains 130-140 g, satisfying the requirements of first-quality carcasses (weight < 80 g) (13). At 8 weeks of age (±3 days), the eggtype quail meat contains more water, protein and minerals compared to meat of adult birds (aged 8 months ± 3 days) (14). The literature review makes clear that Japanese quails are subject to extensive experimental research. The exceptional variety of breeds, strains and production types used in global husbandry practice motivated our detailed research on physicochemical properties of meat in the two Japanese quail breeds, reared in Bulgaria. The purpose of the present study was to investigate the effect of Japanese quail breed on the quality of produced meat. MATERIAL AND METHODS The study was conducted with two Japanese quail breeds Pharaoh (specialized meat-type breed) and Manchurian Golden (all-purpose breed for eggs and meat production). The quails from both groups were slaughtered at 35 days of age, after 4-hour fasting. The initial processing included removal of the skin with feathers. This method was chosen to avoid the possible influence of temperature during carcass scalding on meat colour traits. The slaughter analysis was done as per the protocol described by Genchev and Mihaylov (15). Carcasses were identified by individual numbers and weighed on an ACB plus-300 balance with precision of 0.01 g. Weighed labeled carcasses were arranged in polystyrene foam plates, packed with stretch wrap film and placed at 0-4 0 С for 4 hours. The two breast muscles: m. Pectoralis superficialis (MPS) and m. Pectoralis profundus (MPP) characterised with different morphology and post mortem carbohydrate catabolism were submitted to physicochemical analysis. The ph of MPS and MPP was determined at post slaughter min 30 and hour 4. A portable phmeter NESTO with a glass electrode, Trakia Journal of Sciences, Vol. 11,, 013 18

preliminary calibrated in standard solutions with ph 4.0 and рн 7.0 was used. The electrode of the ph-meter was inserted at a depth of 1 cm into the muscle tissue. The muscle colour coordinates were measured in the CIE L*a*b* system (16). For this purpose, a Lovibond SP60 spectrophotometer (X-Rite Incorporated), previously calibrated with white and black colour standards was used. The values of coordinates L * (white - black), a * (red-green) and b * (yellow-blue) were measured 4 and 4 hours after the slaughter as followed: m. Pectoralis superficialis in the middle third of the medial surface (facies medialis) of the muscle; m. Pectoralis profundus in the middle third of the lateral surface (facies lateralis) of the muscle; Three measurements of colour coordinates were performed in the same muscle area and for the first measurement, the spectrophotometer was always directed longitudinally to muscle fibres. The second and the third measurement were made in the same point, after rotating the device 45 о and 90 о clockwise (17). The arithmetic mean of the three measurements for L *, a * and b * values was retained. The Chroma (С*) = a * b*, Hue angle (h o )= tg -1 (b*/a*) and colour difference Е= L* a * b * were calculated on the basis of a * and b * values (18). The WHC of meat was determined 4 hours after the slaughter by compression of muscle tissue sample over filter paper between two glass slides (19). The WHC was determined by the formula: WHC = А/В.100 where: WHC - water holding capacity of muscles, %; А - weight of muscle samples before the compression, g; В weight of muscle samples after the compression, g. *Note: Higher WHC values correspond to lower WHC of muscles. Data were statistically processed using the classic methods for statistical analysis in MS Excel 003. RESULTS ph values of studied muscles are listed in Table 1. There were no statistically significant differences between Pharaoh and Manchurian Golden quails. On post mortem min 30, рн 1 values of both breast muscles were comparable. The breed-related difference was within 0.8-1.1%. On the 4 th post mortem hour, рн of both breast muscles decreased up to 5.4-5.5. At this time interval, the difference related to breed was also insignificant 0.-1.7%. The established рн values allowed assuming that glycogen reserves of skeletal muscles and the rate of post mortem anaerobic glycolysis in both quail breeds were almost similar. The absolute difference between рн 1 and рн ( рн abs ) for all experimental subjects is varied between 0.7 and 1.1 which corresponded to reduction by 5 to 17%. Average рн abs values of breast muscles were somewhat different depending on the breed. It could be noted that in Pharaoh Quails, рн abs values were lower (0.61 for MPS and 0.6 for MPP). In Manchurian Golden quails, the respective values were 0.67 and 0.64, equivalent to a difference of 8.5% for MPS and 3.3% for MPP. Meat ph during the first post mortem hours had the most substantial effect on water holding capacity of meat. As seen from Table 1, breedrelated difference in WHC of studied muscles was negligible. Table presents the data about muscle colour coordinates in studied breeds. By the 4 th post mortem hour, the between-breed differences between L * (lightness) values were minor and insignificant. In general, L 4h * varied between 39.5 and 51.8, whereas differences between quail breeds were by -.8%. By the 4 th post mortem * hour, L 4h increased by 18.6 to 6.%. In this study, L * 4h of studied muscles in both breeds were within 41.3 and 58.8. 183 Trakia Journal of Sciences, Vol. 11,, 013

Table 1. Physico-chemical characteristics of breast meat Traits m. Pectoralis Superficialis (MPS) m. Pectoralis Profundus (MPP) Pharaoh Manchurian Golden Pharaoh Manchurian Golden рн 30min 6,±0,03 6,1±0,06 6,±0,03 6,1±0,05 min max 5,91 6,38 5,69 6,7 6,03 6,41 5,6 6,5 VC, %,01 3,99,34 3,30 difference,% 1,1 0,8 рн 4h 5,5±0,05 5,4±0,03 5,5±0,03 5,5±0,03 min max 5,1 6,05 5,5 5,64 5,43 5,71 5,3 5,74 VC, % 3,59,5 1,93,38 difference,% 1,7 0, рн abs 0,61±0.05 0,67±0.05 0,6±0.03 0,64±0.05 min max 0,7 0,97 0,38 1,11 0,46 0,87 0,9 1,08 VC, % 34,34 33,41 0, 9,7 difference,% 8,5 3,3 рн relative 0,10±0,01 0,11±0,01 0,10±0,01 0,10±0,01 min max 0,05 0,15 0,07 0,17 0,07 0,14 0,05 0,17 VC, % 33,17 9,66 19,01 7,39 difference,% 8,6 3, WHC 4h 1,4±0,8 3,1±0,8 1,9±0,8 3,7±0,9 min max 15,88 7,43 16,04 36,10 14,46 9,9 18,5 41,34 VC, % 16,88 18,7 16,40 19,90 difference,% 7,3 7,5 Redness values (а*) of breast muscles is varied between 13.9-4. (MPS) and 7.1-1.8 (MPP). On both the 4 th and the 4 th post mortem hours, the values of this colour trait were lower in both studied muscles of Pharaoh quails. A statistically significant difference was present only for MPP on the 4 th post mortem hour. The pigmentation of MPS was most intense by 46.5-6.7% (Р<0.001) on hour 4 and by 9.-35.% (Р<0.001) on hour 4 compared to MPP. During the storage of meat from hour 4 to hour 4, average a* values of MPS and MPP increased by 17.-18% and 15.9-16.7% respectively (Р<0.05 for MPP). The values of the b * coordinate (yellowness) preserved the tendency for lower intensity of the colour of Pharaoh quail meat compared to that of Manchurian Golden breed. The difference between breeds was more pronounced in MPP by 10%, but not statistically significantly. The yellowness values increased between hours 4 and 4 of storage, more intensively for MPP (by 4.9-61.4%). Similarly to redness values, breast muscle yellowness was stronger in MPS. The yellowness of this muscle was higher than that of MPP in the two breeds by 75.7-86.% (Р<0.001) on post mortem hour 4 and by 30-36.8% (Р<0.001) on post mortem hour 4. The difference between breeds on hour 4 was not considerably 3.3% for MPS and 1.6% for MPP. The Chroma values of both breast muscles (С*) on hour 4 (Chroma) were lower in Pharaoh quails. This could be anticipated on the basis of lower а* and b* values of meat in this breed. The statistically significant difference between the breeds for MPP а 4h * values further influenced the С 4h * values (Р<0.01). On post mortem hour 4, average С 4h * values increased by 5.7-7.% for MPS and by.8-35.5% (Р<0.01) for MPP compared to hour 4. The hue angle (h o ) did not differ substantially between groups on hours 4 and 4. It could be affirmed that h o values tended to decrease slightly as the storage term increased. The colour difference E* varied within a rather wide range: between 1.0 and 1.1 for MPS and between 1.9 and 18.3 for MPP. Comparing the average values of the two breeds, E* of both breast muscles were bigger in Pharaoh quails, with difference by 18.% for MPS and 1.3% for MPP. It should be noted that the colour difference was more pronounced for MPP, whose E* values were by 37.-40.3% (Р<0.05) higher than those of MPS. Trakia Journal of Sciences, Vol. 11,, 013 184

Table. Colour characteristics of breast meat Traits m. Pectoralis Superficialis (MPS) m. Pectoralis Profundus (MPP) Pharaoh Manchurian Golden Pharaoh Manchurian Golden L* 4h 44,37±0.586 45,64±0.605 47,45±0.483 46,5±0.850 min max 40,18 49,45 40,4 50,48 4,39 50,63 39,54 51,80 VC, % 6,19 5,93 4,78 8,17 difference,%,8,0 L* 4h 48,39±0.75 47,9±0.663 50,58±0.80 49,9±0.89 min max 4,39 51,93 43,45 5,45 46,1 58,84 41,3 53,64 VC, % 5,80 5,87 6,14 7,05 difference,% 1,0 1,3 a* 4h 17,6±0.399 18,59±0.390 10,83±0.435 1,69±0.458 min max 14,40 1,38 14,57 1,13 7,10 14,61 9,6 17,39 VC, % 10,6 9,38 18,84 16,13 difference,% 5,3 14,6 ** a* 4h 18,50±0.59 19,0±0.67 13,68±0.907 14,86±0.673 min max 13,94 1,50 15,19 4, 9,50 1,81 10, 0,57 VC, % 1,39 14,85 5,68 19,3 difference,% 3,6 7,9 b* 4h 10,91±0,5 11,44±0,36 5,86±0,330 6,51±0,399 min max 8,85 13,6 8,91 14,78 3,68 9,4 4,03 10,60 VC, % 10,84 14,15 6,44 7,41 difference,% 4,6 10,0 b* 4h 1,30±0.494 1,7±0,745 9,46±0.960 9,30±0,874 min max 8,7 15,4 8,49,66 4,86 15,31 3,7 18,50 VC, % 15,56 4,85 39,34 39,88 difference,% 3,3 1,6 C* 4h 0,74±0,44 1,86±0,47 1,38±0,469 14,36±0,473 min max 17,1 4,33 17,08 5,10 9,86 17,06 10,10 18,55 VC, % 10,00 9,66 17,76 14,73 difference,% 5,1 13,8 ** C* 4h,3±0,730 3,10±0,900 16,77±1,190 17,64±0,997 min max 16,1 6,35 18,03 3,94 10,90 5,41 11,13 7,67 VC, % 1,7 16,53 7,48 3,99 difference,% 3,8 4,9 Hue o 4h 1,41±0,034 1,43±0,046 1,75±0,17 1,90±0,151 min max 1,17 1,69 0,98 1,76 0,5 3,76 0,87 3,3 VC, % 11,0 14,48 34,0 35,47 difference,% 1,8 7,8 Hue o 4h 1,9±0,04 1,3±0,068 1,34±0,139 1,56±0,145 min max 0,96 1,51 0,68 1,8 0,64, 0,79 3,17 VC, % 1,54 1,67 40,15 39,40 difference,%,6 14, E* 5,0±0,83 4,40±0,814 8,7±1,307 7,37±1,088 min max 1,45 10,46 1,0 1,14 3,53 18,05 1,9 18,6 VC, % 55,48 71,67 54,71 57,1 difference,% 18, 1,3 DISCUSSION There are no reference values for ph of Japanese quail meat during the first post mortem hours in the available literature, Depending on the feeding pattern, meat ph of 35-day-old Pharaoh quails range between 5.95 and 6.18 185 Trakia Journal of Sciences, Vol. 11,, 013 (0).Depending on the slaughter age, рн 1 of breast muscles ranges between 5.9 and 5.98 (1). Comparative studies on ph of meat from Japanese quails, chickens, partridges and turkeys showed that Japanese quail meat is characterized

with highest ph values both before (6.58) and after rigor mortis (6.38) (). This allowed assuming that glycolysis in muscles of Japanese quails occurred at a slower rate compared to other domestic fowl species and broiler chickens and turkeys in particular. Low ph values during the first post mortem hours, apart its direct effect on WHC, also influence some other organoleptic properties of meat including colour, tenderness, juiciness etc. After ph values have attained the isoelectric point of myofibrillar proteins, which is between рн 5.-5.4, shrinkage of the protein network occurs, accompanied by reduction of meat WHC. Protein matrix shrinkage is associated with attachment and fixation of bivalent ions (Ca + and Mg + ) to negatively charged protein areas, which also results in lower WHC. In our study, the data for WHC indicate a specific relationship between рн abs and WHC with distinct effect on meat WHC. The colour of meat is an organoleptic trait which could be directly evaluated and indicates the topographic area, species, freshness and tenderness of produced meat. Meat colour depends on the amount of heme pigments, and mostly on the chromoprotein myoglobin (Mb) and the post mortem chemical alterations it suffers. The colour traits are also dependent on the amount, the colour and distribution of intramuscular fat, as well as on structural and ultrastructural changes in myofibrillar proteins by the time of rigor mortis. Numerous factors influence the colour of raw chicken meat breed, sex, age, feeding, preslaughter preparation, stunning, slaughter, scalding temperature, method and regimen of cold storage, storage terms etc. (8, 0, 3, 4). Many investigations have reported increase in L* values during the first 4 hours followed by inconsistent changes thereafter. The L* values established by us differed from data from other researchers with respect to breast muscles of Pharaoh Japanese quails. Literature reports indicate values between 33.7-35.4 (0) and 53.7 57 (1).The lightness of breast muscles differs among domestic fowl species: between 38.-39. in goose (8) and 4.6-45.3 in ducks (5). These differences, in our view, could be attributed to genetic influences as well as to the topographic muscle area used for assessment of meat colour and the post mortem period of assessment. In our experiment, L * 4h values of both breast muscles were within the reference limits for this muscle type. The redness or a* values depend primarily on myoglobin content of muscle fibres. It is the main pigment responsible for the colour of fresh meat. With regard to the currently prevailing myoglobin form (oxygenated MbO, reduced Mb or oxidised MMb), meat colour could substantially differ among various assessments (6). This is supported by the rather broad range of published a* values. In available literature on colour traits of Japanese quail breast meat, a* values could be roughly divided as low 9.7 (17, 7), medium 11.7-1.5 (0) and high 13.1-16 (1, 8). The a* values of studied muscles from both quail breeds in this study were higher that cited values, probably because of the higher relative proportion of MbO, which is responsible for the bright red colour of the meat. The MbO content is the primary factor influencing а* values, but the ratio between MbO and Mb is also important (5). Another plausible explanation could be found with the time and site of colour assess,emt. The a* values immediately after the slaughter do not reflect objectively the actual redness of muscles (6, 9). More consistent information could be obtained after the 4 th hour, when the post mortem relationships between myoglobin, oxymyoglobin and metmyoglobin become steadier. The values of the b* colour coordinate are influenced by multiple pigments which could enhance or attenuate the colour in the yellowblue spectrum. Biliary pigments, derivatives of heme, are among the most commonly encountered in the animal organism. Biliverdin for instance, is yellow-coloured. Another group of yellow pigments are carotenoids and flavoproteins, which depending on their form could present one colour or another. During storage of meat, the b* values tended to increase as a result of post mortem changes during the first 48 hours. The published yellowness values vary from 9.9 9.79 (0) and 17.1-18.0 (1). According to some authors, b* values are mainly influenced by the composition of fattening ration. Statistically significantly higher b* values of both breast muscles have been reported after Trakia Journal of Sciences, Vol. 11,, 013 186

dietary supplementation of antioxidants to Japanese quails (8). Chroma values are a main indicator of the amount of myoglobin in muscles and thus, C* values determine the saturation of their colour (30). During the first 4 post mortem hours, there were no considerable changes in muscle myoglobin, which was correspondingly accompanied by insignificant changes in C* values. The differences in hue angle values obtained by the 4 th and the 4 th post mortem hours were not considerable and in agreement to trends, reported by other researchers for beef meat colour (30, 31). They believe that the alterations in colour traits of meat during its storage result in reduction of a* values and had almost no effect on h о values. The slight post mortem changes of meat h о allowed the assumption that h о values could provide reliable information about the changes of meat colour, especially of cooked meat (3). CONCLUSION The ph values of studied breast muscles were similar in both breeds. They allowed affirming that glycogen depots of skeletal muscles and the post mortem anaerobic glycolysis rate were almost comparable in both Japanese quail breeds. The absolute reduction of ph values ( рн abs ) was less pronounced in Pharaoh quails, while the breast meat of this breed had better water holding capacity (WHC). The analysis of meat colour traits showed similar values of L* in both breeds. The а * and b* values indicated a more intensive pigmentation of MPS (Р<0.001). During meat storage, a* values increased from the 4 th to the 4 th hour, especially in MPP (Р<0.05). A similar trend was present for b* values, but differences were not statistically significant. The data for colour coordinates L*, a* and b* allowed for determination of the colour difference ( Е*), which was considerable for MPP (Р<0.05). At the background of lower a* and b* values of Pharaoh quail meat, observed chroma values (С*) were also lower. During storage, C* values increased, with more pronounced differences for MPP (Р<0.01). The hue angle h o did not change significantly during that time, despite the slight tendency towards reduction of values. REFERENCES 1. Barroeta, A.C., Nutritive value of poultry meat: Relationship between vitamin E and PUFA. World Poultry Science Journal, 63:77-84, 006.. Givens, D.I., Animal nutrition and lipids in animal products and their contribution to human intake and health. Nutrients, 1:71-8, 009. 3. Genchev, A. Mihaylova, G., Ribarski, S., Pavlov, A. and Kabakchiev M., Meat quality and composition in Japanese quails. Trakia Journal of Sciences,6,4: 7-8, 008 4. Ribarski, S., Genchev, A. and Atanasova, S., Effect of cold storage terms on physicochemical characteristics of Japanese quail (Coturnix coturnix japonica) meat. Agricultural Science and Technology, 5, 1:16-133, 013 5. Antipova, L.V., Makarov, А.V., Potential for a broader assortment of functional foods produced from mechanically deboned quail meat. In: Proceedings from the International Scientific Practical Conference on New Trends in Poultry Meat and Eggs Production, VNIIPP State Establishment, October 17-18 006 (Ru). 6. Lonita, L., Popescu-Miclosanu, E., Roibu C. and Custura, I., Bibliographical study regarding the quails meat quality in comparison to the chicken and duck meat. Lucrari Stiintifice, 56, 4-9, 008. 7. Drbohlav, V. and Drbohlavova, D., Effect of storage upon meat quaility traits in broiler chickens. Food Production Science, ІІІ, 1:5-9, 1987. 8. Okruszek, A., Ksiazkiewicz, J., Woloszyn, J., Haraf, G., Orkusz, A. and Szukalski, G., Changes in selected physicochemical parameters of breast muscles ofgeese from Polish conservation flocks depending on duration of thepost slaughter period. Arch. Tierz., Dummerstorf, 51, 3:55-65, 008. 9. Barbut, S., Colour measurements for evaluating the pole soft exudative (PSE) occurrence in turkey meat. Food Res. Int., 6:39-43, 1998. 10. Genchev, А., Ribarski, S. Afanasjev, G., Blohin, G., Fattening capacities and meat quality of Japanese quails of Pharaoh and White English breeds. Journal Central European Agriculture, 6, 4:501-505, 005. 187 Trakia Journal of Sciences, Vol. 11,, 013

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