Lipid and fatty acid composition of rabbit meat: Part 1.-Apolar fraction

The apolar lipid contents and the fatty acid composition of meat from two rabbit breeds (New Zealand white and commercial hybrid HYLA) fed two commercial diets of different protein and crude fibre levels have been studied. The total and apolar lipid content of meat from both rabbit breeds ranged from 4·9 to 10·5% (wet weight). The individual lipid classes of the apolar fraction are described. Triglycerides accounted for more than 80% of total apolar lipids. The fat from rabbit meat is comparatively richer in palmitic acid (about 40% being always the major fatty acid), in linoleic acid and in myristic acid and poorer in stearic acid than other meats. Although differences in the fatty acid compositions of meat were observed, only clear influences of age, sex, breed, and/or feeding on the fatty acids C-16:0, C-18:0 and C-18:2 of total and apolar lipids were found.     

Effect of fat-enriched diets on rabbit meat fatty acid composition

The effects of beef tallow-, soya and sunflower olein- and soya bean oil-enriched (3%) diets on the chemical and fatty acid composition of total, a polar and polar lipids of rabbit meat have been studied. No significant differences (P > 0.05) in the meat chemical composition were observed between groups. However, a large effect of the diet on the total and apolar lipid fatty acids was found, with C18:1 and C18:2 the most affected fatty acids. The influence of the diets on the fatty acids of the polar fraction was less marked. It is concluded that the enrichment of the rabbit diet with either soya and sunflower oleins or soya bean oil allows the production of rabbit meat with a higher unsaturation degree than is obtained by using conventional diets, which constitutes an important nutritional benefit to the human being.     

饲养因素对兔肉脂肪酸组成影响的研究进展

兔肉除了其\     

饲养因素对兔肉脂肪酸组成影响的研究进展

兔肉除了其"四高"(高赖氨酸、高蛋白质、高磷脂、高消化率)和"三低"(低胆固醇、低脂肪、低热量)的特点以外,兔肉中脂肪酸组成作为其功能性的重要方面之一被广泛研究。本文综述了饲养对兔肉中脂肪酸的抗菌性、抗氧化性、降血脂、保护改善肝脏等功能性质的影响,以及饲养方式、日粮类型和日粮饲喂等因素对兔肉中脂肪酸组成的影响,旨在为指导肉兔养殖和提高兔肉功能品质提供参考。     

气相色谱-质谱联用分析四川白兔肌内脂肪酸的组成

以四川白兔的前腿肌(foreleg muscle,FL)、后腿肌(rear leg muscle,LL)、背最长肌(longissimus dorsi,LD)和腹部肌肉(abdominal muscles,AM)为实验原料,经三氯甲烷-甲醇浸提法提取,采用气相色谱-质谱联用仪测定不同性别、日龄和部位四川白兔肌内脂肪酸组成,为四川白兔肉的营养价值提供基础数据。结果表明:四川白兔肌内的主要脂肪酸有12种,其中棕榈酸、硬脂酸、油酸、亚油酸的累积含量占总脂肪酸含量的80%左右。兔肉肌内脂肪中主要是不饱和脂肪酸,尤以多不饱和脂肪酸居多,占40%左右,略高于饱和脂肪酸含量。性别对脂肪酸组成基本无影响,日龄对脂肪酸组成有一定的影响,各部位间的脂肪酸组成差异不显著(P0.05)。     

Cholesterol content and fatty acid composition of rhea meat

The influence of species and muscle on the intramuscular fat content, cholesterol content and fatty acid composition of Greater and Lesser Rhea meat were evaluated. Muscle has no influence (P>0.05) on any of these characteristics. Neither intramuscular fat (1.23%) nor cholesterol content (57 mg/100 g) differed (P>0.05) between species. Despite differences (P<0.05) in the percentage of individual fatty acids, total saturated fatty acids (33.1%) did not differ (P>0.05) between species, while total monounsaturated fatty acids (26.8 vs 32.2%) was lower (P<0.05) and total polyunsaturated fatty acids (39.7 vs 33.6%) higher (P<0.05) for Greater than Lesser Rhea.     

风干牦牛肉氨基酸与脂肪酸组成分析评价

通过对风干牦牛肉原料及成品中氨基酸与脂肪酸的含量进行测定,分析其组成变化,并对风干牦牛肉的营养价值进行评价。结果显示:原料肉和风干牦牛肉均含有十八种氨基酸和十四种脂肪酸,且风干牦牛肉的氨基酸和脂肪酸总量分别高于原料肉1.34g/100g干物质和0.62%（p<0.05）。风干牦牛肉的氨基酸总量为81.14g/100g干物质,EAA/TAA为39.45%,EAA/NEAA为65.15%。脂肪酸总量为97.97%,P:S为0.32,接近理想模式,n-6:n-3为1.4,处于理想范围。因此可以判断风干牦牛肉是一种具有独特风味的优质蛋白质来源,也是具有均衡脂肪酸的高营养价值的肉制品。      

兔肉脂肪酸组成的气相色谱法分析

采用极性毛细管柱气相色谱法,测定了兔肉脂肪酸组成的相对百分含量和实际含量.测定结果表明,此方法能准确分离出兔肉中的主要8种脂肪酸:豆蔻酸、棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸、亚麻酸和花生酸,有较好的精密度、重复性、可靠性.     

白牦牛肉脂肪酸组成及分析

为分析白牦牛肉的脂肪酸组成及功能特性,采用气相色谱-质谱联用仪(GC-MS)对甘肃天祝白牦牛肉进行定性定量测定,并与当地黄牛肉进行比较。结果表明:白牦牛肉与黄牛肉中的脂肪酸均以饱和脂肪酸为主,在单不饱和脂肪酸和多不饱和脂肪酸尤其是功能性脂肪酸方面,两者有显著的差异(P<0.05或P<0.01),牦牛肉脂肪酸种类更丰富、营养价值更高。     

伊拉兔肉肌内脂肪酸组成及温度对其脂肪氧化的研究

研究了伊拉肉兔后腿肉的肌内脂肪含量,并分析测定了其脂肪酸组成,同时研究了兔腿肉在常温(15±0.5)℃和低温(4±0.5)℃贮藏条件下的脂肪氧化稳定性。结果表明,兔腿肉肌内脂肪主要含有19种脂肪酸,其中棕榈酸(16∶0)、硬脂酸(18∶0)、油酸(18∶1)、亚油酸(18∶2)的总含量占脂类总脂肪酸含量的71.06%左右。伊拉兔肉肌内脂肪中主要是不饱和脂肪酸,尤以多不饱和脂肪酸居多。在常温(15±0.5)℃和低温(4±0.5)℃贮藏条件下,兔腿肉POV、TBA值的差异极显著(p<0.01)。常温条件下,第5d兔肉出现异味并逐渐变成臭味,而低温条件下,第7d才开始出现轻微异味,低温冷藏对保证肉品质量有重要意义。      

Fat deposition, fatty acid composition and meat quality: A review

This paper reviews the factors affecting the fatty acid composition of adipose tissue and muscle in pigs, sheep and cattle and shows that a major factor is the total amount of fat. The effects of fatty acid composition on meat quality are also reviewed. Pigs have high levels of polyunsaturated fatty acids (PUFA), including the long chain (C20-22) PUFA in adipose tissue and muscle. The full range of PUFA are also found in sheep adipose tissue and muscle whereas cattle ‘conserve’ long chain PUFA in muscle phospholipid. Linoleic acid (18:2n − 6) is a major ingredient of feeds for all species. Its incorporation into adipose tissue and muscle in relation to the amount in the diet is greater than for other fatty acids. It is deposited in muscle phospholipid at a high level where it and its long chain products eg aracidonic acid (20:4n − 6) compete well for insertion into phospholipid molecules. Its proportion in pig adipose tissue declines as fat deposition proceeds and is an index of fatness. The same inverse relationships are not seen in ruminant adipose tissue but in all species the proportion of 18:2n − 6 declines in muscle as fat deposition increases. The main reason is that phospholipid, where 18:2n − 6 is located, declines as a proportion of muscle lipid and the proportion of neutral lipid, with its higher content of saturated and monounsaturated fatty acids, increases. Oleic acid (18:1cis − 9), formed from stearic acid (18:0) by the enzyme stearoyl Co-A desaturase, is a major component of neutral lipid and in ruminants the same enzyme forms conjugated linoleic acid (CLA), an important nutrient in human nutrition. Like 18:2n − 6, -linolenic acid (18:3n − 3) is an essential fatty acid and is important to ruminants since it is the major fatty acid in grass. However it does not compete well for insertion into phospholipid compared with 18:2n − 6 and its incorporation into adipose tissue and muscle is less efficient. Greater biohydrogenation of 18:3n − 3 and a long rumen transit time for forage diets also limits the amount available for tissue uptake compared with 18:2n − 6 from concentrate diets. A positive feature of grass feeding is that levels of the nutritionally important long chain n − 3 PUFA are increased ie EPA (20:5n − 3) and DHA (22:6n − 3). Future research should focus on increasing n − 3 PUFA proportions in lean carcasses and the use of biodiverse pastures and conservation processes which retain the benefits of fresh leafy grass offer opportunities to achieve this. The varying fatty acid compositions of adipose tissue and muscle have profound effects on meat quality. Fatty acid composition determines the firmness/oiliness of adipose tissue and the oxidative stability of muscle, which in turn affects flavour and muscle colour. Vitamin E is an essential nutrient, which stabilises PUFA and has a central role in meat quality, particularly in ruminants.     

坛子肉中氨基酸和脂肪酸营养品质评价

目的评价坛子肉中氨基酸和脂肪酸的营养品质。方法运用多种方法对坛子肉中氨基酸和脂肪酸的组成及含量进行测定,并用必需氨基酸指数法(essential amino acid index method,EAAI)、氨基酸评分法(amino acid score, AAS)、化学评分法(chemical score, CS)评价坛子肉中蛋白质的营养价值。结果坛子肉中氨基酸总量为20.76%±0.21%, 8种必需氨基酸占氨基酸总量的42.60%, 4种鲜味氨基酸占氨基酸总量的36.90%,AAS和CS均表明第一限制性氨基酸为色氨酸。坛子肉中粗脂肪含量为28.15%±0.31%,不饱和脂肪酸占脂肪酸总量的70.79%±0.31%。必需氨基酸占氨基酸总量的38.15%,必需氨基酸与非必需氨基酸的比值为61.68%。结论坛子肉是一种具有独特风味的优质蛋白源以及具有均衡脂肪酸的高营养价值的肉制品。     

Chemical and fatty acid composition of meat from Spanish wild rabbits and hares

The differences in the chemical and fatty acid compositions between the meats of five Spanish wild rabbits (Oryctolagus cuniculus) and five Spanish wild hares (Lepus europaeus) for foreleg, loin, hindleg and perirenal fat have been studied. Only significant differences (P<0.05) in the meat chemical composition were observed between rabbits and hares for dry matter and fat in loins, and for ash in hindlegs. Significant differences (P<0.05) between saturated fatty acids in foreleg and perirenal fat and between unsaturated C-181 and C-182 fatty acids in loins were observed.

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Chemische- und Fettsäurenzusammensetzung des Fleisches von spanischen Wildkaninchen und Hasen

Zusammenfassung Spanische Wildkaninchen und Hasen unterscheiden sich in der Fleischzusammensetzung signifikant (P<0.05) nur in bezug auf den Gehalt an Trokkenmasse und Fett in den Lenden und in bezug auf den Mineralstoffgehalt der Hinterbeine. Signifikante Unterschiede waren auch bei den gesättigten Fettsäuren in Vorderbeinen und Nierenfett und zwischen den ungesättigten Fettsäuren C-18l und C-182 in den Lenden zu beobachten.

     

不同畜禽肌肉脂肪酸组成的对比分析

采用GC-MS测定猪、牛、鸡、兔后腿肌脂肪酸组成的相对百分含量和实际当量,测定结果表明四者的主要脂肪酸组成有17种,其中棕榈酸（16∶0）、硬脂酸（18∶0）、油酸（18∶1n-9）、亚油酸（18∶2n-6）和花生四烯酸（20∶4n-3）的总含量占肌肉总脂肪酸含量分别为84.35%、79.71%、81.78%、81.19%。n-6/n-3比率猪肉最高,鸡肉、兔肉次之,牛肉最低。就综合营养价值而言,兔肉最高,牛肉、鸡肉次之,猪肉最低。      

Cholesterol content and fatty acid composition of ostrich meat as influenced by subspecies

Two muscles, the m. gastrocnemius and m. iliofibularis, were excised from the left legs of six Red Neck (Struthio camelus massaicus) and six Blue Neck (Struthio camelus australis) ostriches and analysed for lipid and cholesterol content and fatty acid composition. Total lipid (1.43 g 100g ) and cholesterol content (65.63 mg 100g ) did not differ (ps> 0.05) in any muscle between subspecies. Although the percentage of some individual fatty acids differed (p < 0.05), the total percentage of saturated fatty acids and total monounsaturated fatty acids was similar (p > 0.05) between subspecies in both muscles. Although the percentage total polyunsaturated fatty acids was higher (p < 0.05) in Blue Necks (23.78%) than in Red Necks (23.65%) in the m. gastrocnemius, but not (p > 0.05) in the m, iliofibularis, the difference of 0.13% is probably of no practical significance.     

肉中脂肪酸组成与健康关系的研究进展

综述了肉中各类脂肪酸与人体健康的关系以及影响肉中脂肪酸组成的主要因素(包括地域、品种、日龄、饲料成分、饲养方式、加工条件等),并对保持肉中脂肪酸组成平衡的方法进行了展望,为人们通过合理生产加工从而获得更加优质的肉制品提供了理论依据。      

Irradiation effect on fatty acid composition and conjugated linoleic acid isomers in frozen lamb meat

The effect of gamma radiation processing on the lipid content, fatty acid composition and conjugated linoleic acid (CLA) profile in frozen lamb meat was investigated. Samples of longissimus thoracis muscle from lambs fed lucerne basal diets either unsupplemented or supplemented with polyunsaturated vegetable oils were irradiated (7 kGy) and analysed. CLA contents in lamb meat did not affect (P > 0.05) the levels of lipid oxidation induced by the irradiation. No significant differences (P > 0.05) were observed for fatty acid composition, related nutritional indexes (n − 6/n − 3 and PUFA/SFA), as well as for total lipid and CLA contents, between non-irradiated (control) and irradiated meat samples. In contrast, meat irradiation affected the relative proportions of total trans, trans and cis/trans CLA isomers (P < 0.001), in addition to the percentage of some minor individual CLA isomers (t11, t13 and t9, t11, with P < 0.05 and P < 0.001, respectively). The percentage of total cis/trans CLA isomers slightly decreased in irradiated samples, while the relative proportion of total trans, trans isomers slightly increased. This observation may be explained by the higher susceptibility to autoxidation of the cis double bond relative to the trans configuration.     

Effect of genetic rabbit lines on lipid content, lipolytic activities and fatty acid composition of hind leg meat and perirenal fat

The influence of genetic origin on lipid content, lipolytic activities and fatty acid composition of rabbit leg meat and perirenal fat was studied and changes in free fatty acids and oxidative parameters during refrigerated storage evaluated. Three rabbits lines were used, line R selected for growth rate and lines V and A selected for litter size at weaning. Line R had higher fat contents and higher lipolytic activities in the meat of the hind leg than lines A and V. Differences between lines were found in the fatty acids of the meat and perirenal fat. Lower SFA and higher PUFA percentages were found in line A. Free fatty acids and oxidative parameters were little influenced by rabbit line. Animals were measured at the same stage of maturity, thus it can be considered that differences found between lines are genetic differences and not differences due to the degree of maturity.     

Effect of crossbreeding and gender on meat quality and fatty acid composition in pork

This study considers the effect of crossbreeding and gender (barrows; gilts) on meat quality and intramuscular and subcutaneous fatty acid composition in pork. The sire lines included Large White (LW), Duroc (D) and Pietrain (P) and the dam line was Landrace (LR)×LW, producing LW×(LR×LW), D×(LR×LW) and P×(LR×LW). Pork samples were removed from Longissimus dorsi (LD) and Semimembranosus (SM) muscles and subcutaneous fat (SCF). There were no important differences in meat quality parameters but D×(LR×LW) had the highest percentage of intramuscular fat. Castrated males had more intramuscular fat and more intense meat colour than female pigs. The Large White and Duroc sire line had saturated fatty acids (SFA) in SM, whereas the Pietrain sire line was significantly higher than Duroc sire line in the concentration of polyunsaturated fatty acids (PUFA), PUFA/SFA (P/S) and the n-6/n-3 ratio. The concentrations of SFA and monounsaturated fatty acids (MUFA) in SCF were significantly higher in LW×(LR×LW) and P×(LR×LW), respectively. No differences were found in the percentage of PUFA, P/S and n-6/n-3 ratio between D×(LR×LW) and P×(LR×LW). Female pigs had the most polyunsaturated intramuscular and subcutaneous fat. The results demonstrate small differences in fatty acid compositions among sires.     

Manipulation of the fatty acid composition of pig meat lipids by dietary means

Pigmeat products have been associated with an unhealthy image due to the relative proportions of polyunsaturated and saturated fatty acids. The aim of this experiment was to improve the fatty acid profile of the carcass fat by feeding various dietary sources of fat. Groups of 10 female Large While × Landrace pigs were fed one of four experimental diets. Five in each group were slaughtered at 70 kg live weight and the remaining five at 100 kg live weight. The diets were offered ad libitum and daily intake was recorded. The diets were based on barley, soya bean meal and fishmeal. Diet 1 contained 50 g tallow kg^?1, a relatively saturated fat, and diets 2, 3 and 4 contained 50 g soya oil kg^?1, an unsaturated fat. Diet 3 also contained 7.5 g GLA oil kg^?1, which is rich in gamma linolenic acid, with the aim of increasing the production of arachidonic acid in the body fat. Diet 4 was supplemented with 9.5 g EPAnoil kg^?1, which is rich in eicosapentaenoic acid and docosahexaenoic acid. There were no significant differences between dietary treatments in performance (daily liveweight gain or the efficiency of food conversion to liveweight gain) of the pigs slaughtered at 70 kg live weight, but small differences were observed at 100 kg live weight, where pigs on treatments 2, 3 and 4 performed slightly better than those on treatment 1. At both slaughter weights the lipid content of the m semitendinosus was higher than that of the m longissimus dorsi (approximately 24 and 13 g kg^?1, respectively). The pattern of fatty acids in the dietary fat was reflected to varying degrees in the carcass fat. Diet 1 resulted in the highest levels of palmitic, palmitoleic, stearic and oleic acids whereas diets 2, 3 and 4 gave high levels of linoleic and linolenic acids. The extra gamma linolenic acid in diet 3 did not result in a consistently significant increase in the production of arachidonic acid. The supplement of EPAnoil gave significant increases in the levels of eicosapentaenoic and docosahexaenoic acids in the body lipids. The polyunsaturated to saturated fatty acid ratio of the body lipid was increased with diets 2, 3 and 4 to about 1.0. In spite of high levels of linoleic acid, there were no adverse effects during the processing of the carcasses and the taste panel evaluation did not reveal any treatment differences.