COMPARISON OF THE CHEMICAL COMPOSITION AND FATTY ACIDS OF THE INTRAMUSCULAR FAT OF GOAT KID AND RAM LAMBS MEAT

Roman Niedziółka, Krystyna Pieniak-Lendzion, ELżbieta Horoszewicz
Departament Sheep and Goat Breeding, University of Podlasie in Siedlce, Poland

ABSTRACT

In the experiment, goat kids of white improved breed and ram lambs of the Polish Lowland sheep fattened up to 150 days, were studied. After weaning, the animals at the age of about 70 days old were fattened "ad libitum" with all-mash pelleted feed CJ the additive containing 6.1 MJ EN and 182 g of crude protein, and meadow hay additionally. The main aim our study was determined the differences in fatty acids compositions of intramuscular fat of goat kid and ram lambs, fed with the same feed and kept in the same conditions. Results of the study showed that lambs were significantly heavier (36.64 kg) and had got a higher weight of warm carcass (16.67 kg). The kid meat showed significantly higher content of protein (20.21%) and mineral compounds (1.13%) and lower fat content (2.28%). Lamb meat contained more dry matter as well as crude fat and less protein and mineral elements than goat meat. Muscles of goat kid characterized 3.55 p.j. (percentage units) lesser contents of palmitic acid (C_16:0 ) and 4.33 p.j. of stearinic acid (C_18:0 ). Significance of differences was confirmed statistically. Among determined monosaturated acids dominated oleinic acid (C_18:1 ): in goat kid tissue 54.1% and ram lambs tissue 47.5%. From among acids polyunsaturated significant differences stepped out among fatty acids; C_18:2 , C_18:3 , C_20:4. In the researcher's study, this indicator was slightly below this optimum ratio and ranged from 1.60 for goats and 1.29 for rams. In the experiment, favorable proportion of UFA:SFA characterized of goat kids (1.69) incomparision with ram lambs (1.22). The differences among studied animals were significant statistically.

Key words: kids, rams, meat, fatty acids.

INTRODUCTION

Recently, markets of food products adapt to different requirements of contemporary consumer, insisting of lean easily digested meat, haring high quality and taste. High interest of the animal’s fat composition is observed, resulting from multiple functions in the diet. Excessive consumption of this kind of products can increase the cholesterol level in blood, leading to closing the blood vessels and infarct [10, 12, 14, 15]. According to many authors [1], the chemical composition and characteristics of fatty acids in the muscular tissue of ruminants depends, among other factors, on the quality age, location of fat tissue an the type of feed the animals are fed with.

The main aim our study was determined the differences in fatty acids compositions of intramuscular fat of goat kid and ram lambs, fed with the same feed and kept in the same conditions

MATERIAL AND METHODS

Kids males (n=16) of White Improved breed and ram lambs (n=16) of Lowland Polish breed were used as the experimental material. The study was carried out in rotation of two repetitions. After weaning, the animals at the age of about 70 days old were fattened "ad libitum" with all-mash pelleted feed CJ the additive containing 6.1 MJ EN and 182 g of crude protein, and meadow hay additionally. The fattening was conducted until the age of 150 days.

The slaughtering and the evaluation of carcass value were carried out according to methods approved by the Animal Science Institute for sheep. After 24- hours of chilling in temperature 4°C, the carcasses were divided into half-carcasses. The right half of the carcasses was dissected into meat, bones and fat.

The fatty acids profile in intramuscular fat extracted from adductor muscle (m. adductor) was determined by Soxhlet method. Determination of fatty acids profile was performed by gas chromatography Chrom 5 deverce fitted with the fire-ionizing detector (FID), a glass column, a SILAR 5CP spiral with a 10% level with inner diameter 4mm and 2.5 meter lenght, nitrogen as transferring gas at float rate 30ml∙min.^-1, column temperature was 200°C and detector temperature was 250°C.

The results were statistically analyzed of variance followed by a Tukey test, and by computer program SPSS PC [7].

RESULTS AND DISCUSSION

Results of the study showed that lamb kids were significantly heavier (36.64 kg) and have got a higher weight of warm carcass (16.67 kg) and higher weight of right of fatness (8.16 kg) just before slaughter. However goat kid weighted near slaughter 31.75 kg and they had about 2 kg lower mass of carcass in comparison to ram lambs. There were no clear differences in slaughter value and meat content in the goatkid fatness with significantly reduced fat tissue (15.61 and 17.79%) (Fig. 1). The effect of animal species and the year of study on body weight before slaughter, right-half carcass weight and fat contain in half carcasses was found. The similar results were shown by Sanz-Sampelayo et al. [10] and Taylor et al. [13].

The kid meat showed significantly higher content of protein (20.21%) and mineral compounds (1.13%) and lower fat content (2.28%) . Lamb meat contained more dry matter as well as crude fat and less protein and mineral elements than goat meat (Fig. 2). The results obtained correspond to the values achieved by Pieniak-Lendzion et al. [9], and Gruszecki et al. [4] in their research.

The effect of animal species and the year of study on body weight before slaughter, right-half carcass weight and fat contain in half carcasses were found. The similar results were shown by Sanz-Sampelayo et al. [11], and Arsenos et al. [1]. Statistically significant differences for chemical composition of muscle tissue with regard to the animal species and the year of study were proved. Protein and minerals contains were larger, whereas fat contain was smaller in muscle tissue of kids. Similar results were proved by Babiker et al. [2], Pieniak-Lendzion et al. [9].

Investigation resulted in finding that intramuscular fatt of goat kid characterized generally advantageous profile of fatty acids that the one of ram lambs (Table 1). The comparative analysis of results shows the 3.55 p.j. lesser content of palmitic acid ( C_16:0 ) and 4.33 p.j. of stearinic one ( C_18:0 ). The difference was statistically significant. Kalinowska and Pustkowiak [6] obtained lower results palmitic acid C_16:0 – 15.86, stearic acid C_18:0 – 17.70%. Jonshon [5] obtained the results higher by 3%.

Among fatty acids, playing special role in human body organism, statistically significant differences were find in oleinic acid content (C_18:1 ), in goat kid and ram lambs respectively haring 54.1 and 47.5% of that ones. The mentioned content of fatty acid influenced the sum of monounsaturated acids (MUFA). Furthermore, significant differences in the content of polyunsaturated fatty acids ( C_18:2 , C_18:3 , C_20:4 ) was noticed. The studied muscles of goat kid contained move mentioned acids than the analogous tissue of ram lambs.

The animal species significantly influenced the percentage participation of majority of fatty acids.

The intramuscular fat of goat kid characterized significantly lesser participation of saturated fatty acids (SFA) by 7.91 p.j. and a higher content of unsaturated ones (UFA) by 7.91 p.j., and among them, monounsaturated acids (MUFA) by 7.14 p.j. in comparison with ram lambs. Statistical differences in content of polyunsaturated fatty acids were not found (PUFA).

Comparison of fatty acids in analyzed muscles, dependently of the kind of animal during two years showed statistically significant differences between years of investigations. However, no differences in percentage contents of the following acids were ascertained: C_17:1 , C_18:0 , C_18:1 , C_18:2.

It was demonstrated that habitat factor the experimental years and specific animals significant effect of on contents fatty acids; C_18:3 , C_20:1 , C_20:4 . In case of fatty acids; C_14:0 , C_16:1, C_17:0 differences between the specific animals not always have significant.

Proportion of unsaturated (UFA) to saturated (SFA) acids is the significant indicator of fat quality. From the dietary point of view, the relationships between saturated and unsaturated acids are important for a consumer, and their optimal ratio is 2:1 [8]. In the experiment, advantageous proportion of UFA:SFA characterized goat kids (1.69) in comparison with ram lambs (1.22). The differences between animal species were significant statistically.

Results of the study showed higher quality of goat meat in comparison to lambs meat, confirm evader data obtained by Banskalieva et al. [3], Gruszecki et al. [4], Pieniak-Lendzion et al. [9], Velasco et al. [14].

CONCLUSIONS

1. The goat kid meat from the experiment showed significantly higher content of protein (20.21%) and mineral compounds (1.13%) and lower fat content (2.28%)

2. In the experiment significant differences in fatty acids composition in intramuscular fatt, dependently on animal species, were stated.

3. The most beneficial, from dietary point of wiew, composition of fatty acids, i.e. the highest content of unsaturated ones and the lowest content of saturated acids, characterized the intramuscular fatt of goat kids.

4. The analyzed intramuscular fat of goat kids characterized by move beneficial participation of MUFA and PUFA than the ram lamb ones.

REFERENCES

1. Arsenos G., Zygoyjannis D., Kofidis D., Kotsaounis N., Stamataris C., 2000. The effects of breed slaughter weight and nitritional menagement on cholesterol content of lamb carcasses. Small. Rum. Res. 36, 275-283.

2. Babiker S.A., El Khider I.A., Shafie S.A., 1990. Chemical composition and quality attributes of goat meat and lamb. Meat. Sci. 28, 273.

3. Banskalieva V., Sahlu T., Goetsch A.L., 2000. Fatty acid composition of goat muscles and fat depots; a review. Small Rum. Res. 37, 255-268.

4. Gruszecki T., Lipecka Cz., Szymanowska A., Wierciński J., Junkuszew A., 1999. Skład kwasów tłuszczowych w wewnštrz-mięœniowym tłuszczu owiec i kóz [Composition of fatty acids in the intermuscular fat of the sheep and goats]. Zesz. Nauk. Prz. Hod. 43, 87-94 [in Polish].

5. Johnson D.D., Eastridge J.S., Neubauer D.R., McGowan P., 1995. Effect of sex class on nutrient content of meat from young goat. J Anim. Sci. 73, 296-301.

6. Kalinowska B., Pustkowiak H., 2000. Zawartoœć kwasów tłuszczowych i cholesterolu w mięsie i podrobach koŸlšt tuczonych do masy ciała 16 kg [The content of fatty acids and the cholesterol in meat and the goatling's offals fattened to mass of body 16 kg]. Zesz. Nauk. AR Wroc. 399, 165-157 [in Polish].

7. Microsoft Corp., 1985. Introduction About this Manual Running SPSS/PC the SPSS/PC Tutorial.

8. Nestel P. J., 1987. Polyunsaturated fatty acids (n-3, n-6). Am. J. Clin. Nutr. 45(5), 1161-1167.

9. Pieniak - Lendzion K., Niedziółka R., Szeliga W., 2000. Charakterystyka wybranych cech jakoœciowych mięso koziołków i tryczków. [Characterization of selected meat quality traits of kids and ram lambs]. Rocz. Nauk. Zootech., Supl. 5, 173-177 [in Polish].

10. Santos-Silava J., Bessa J., Bessa R.J.B., Santos-Silva F., 2002. The effect of genotype feeding system and slaughter weight on the quality of light lambs. II Fatty acid composition of meat Livestock Production Science, Portugal 77, 187-194.

11. Sanz-Sampelayo M.R., Lara L., Prito I., Gil-Extremera F., Boza J., 1993. Body compo- sition and energy metabolism of pre-ruminant kids and lambs. Agr. Prod. Anim. 8, 1, 5-15.

12. Œwistak E., Sawicka B., Rejman K., Berger S., 1996. Żywienie a umieralnoœć z powodu chorób dietozależnych [The feeding and the death-rate with reason of diseases the dependent from diet]. Rocz. PZH 47(3), 303 [in Polish].

13. Taylor S.C., Murrey J.I., Thonney M.L., 1989. Breed and sex differences among equally mature sheep and goat. 4; Caracass muscle, fat and bone. Anim. Prod. 49, 3, 385-409.

14. Velasco S., Caneque V., Lauzurica S., Perez C., Hidobro F., 2004. Effects of different feeds on meat quality and fatty acids composition of lambs fattened at pasture. Meat Sci. 66, 457-465.

15. Ziemlański S., 1996. Żywienie a zdrowie [The feeding and heatlh]. Przem. Spoż. 50 (10), 4 [in Polish].

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