蒙古斑点马不同部位脂肪和肌肉组织中脂肪酸组成的比较研究

通过对蒙古斑点马不同部位脂肪和肌肉组织中脂肪酸组成进行分析比较,旨在明确蒙古斑点马体脂脂肪酸组成特点。选择3 匹成年蒙古斑点马,屠宰后采集肾周、肠周和皮下脂肪以及肩肌、背最长肌和臀肌样品,利用气相色谱法测定脂肪酸组成及含量。结果表明：蒙古斑点马不同脂肪组织中均检出19 种脂肪酸,其中饱和脂肪酸（saturated fatty acid,SFA）含量34.77%～37.38%,不饱和脂肪酸（unsaturated fatty acid,UFA）含量达60%以上,UFA中单不饱和脂肪酸（monounsaturated fatty acid,MUFA）含量33.04%～36.39%,多不饱和脂肪酸（polyunsaturated fatty acid,PUFA）含量26.47%～27.51%,其中皮下脂肪C10:0、C18:0、C20:0含量显著低于肾周和肠周脂肪（P＜0.05）;MUFA在皮下脂肪的沉积程度较其他2 个部位高,但均无统计学差异;PUFA中C18:3 n-3含量最高,其在各脂肪组织间无显著差异。3 个不同部位肌肉中均检出15 种脂肪酸,其中SFA含量占总脂肪酸含量的38.32%～40.04%,MUFA含量占35.70%～40.19%,PUFA含量占15.25%～20.33%;SFA中背最长肌和臀肌C12:0含量显著高于肩肌（P＜0.05）,其余SFA在不同部位肌肉间无显著差异;MUFA中背最长肌C16:1含量显著高于肩肌和臀肌（P＜0.05）;肩肌n-6/n-3 PUFA比值显著高于背最长肌和臀肌（P＜0.05）;皮下脂肪的C18:3 n-3和总PUFA含量显著高于背最长肌（P＜0.05）。综上所述,蒙古斑点马不同部位脂肪和肌肉组织脂肪酸组成各具特点,但UFA含量均较高。     

Conjugated linoleic acid (CLA) and polyunsaturated fatty acids in muscle lipids of lambs from the Patagonian area of Argentina

The concentrations of fatty acids were measured in total lipids, triacyglycerol and phospholipid fractions of intramuscular fat (IMF) from the Longissimus dorsi (LD) muscle of 10 lambs reared to approximately 30kg live weight on natural pasture with their dams. Fatty acid composition was also measured in 25 (five of each) Semitendinosus (ST), Semimembranosus (SM), Rectus femoris (RF), Gluteus (GLU) and Tensor fascia latea (TFL) muscles. Intramuscular fat percentages were similar for all muscles. Aspects of the fatty-acid patterns of relevance to human nutrition tended to favor the leg muscles with lower saturated fatty acids (SFA %), n-6/n-3 fatty acid ratios (p<0.01) and higher concentrations of the conjugated linoleic acid (CLA) (p<0.05). The estimated fatty acid concentrations (mg/100g of meat) showed higher contribution of arachidonic (C20:4 n-6), eicosapentanoic (C20:5 n-3), docosapentanoic (C22:5 n-3) and docosahexanoic (C22:6 n-3) acids in leg compared to LD lipids.     

Biochemical and technological characteristics of hot chicken meat

In the hot breast and leg muscles of broiler chicken the level of ATP, the 'R' value, the lactic acid content, the pH value, the length of sarcomers, the water and fat retention capacity, the fat emulsion stability, thermal drip, and the extractability of protein fraction were investigated. It was found that in the breast muscles the onset of rigor mortis commenced within 30–60 min, and in the leg muscles as early as 15–30 min after killing of the birds. The deepest rigor mortis occurred between the first and fourth hour, and then gradually declined, sooner in the leg than in the breast muscles. The addition of sodium chloride (2.0–2.5%) to the minced pre-rigor meat not later than 40 min after slaughter, or better, an injection of NaCl brine into intact muscles 15 min after slaughter of birds, preserved their good technological properties.
The tenderness and the thermal drip of hot salted and chilled salted muscles showed no significant differences, but water retention and fat emulsifying capacity were better in the hot salted meat samples. The hot salted and cooked muscles were preferred by the sensory panel to corresponding samples of chilled muscles.
From the hot salted chicken meat more sarcoplasmic and myofibrillar proteins were extracted than from meat salted after chilling. However, after frozen storage the extractability of myofibrillar proteins were higher in the salted chilled meat.     

A comparison of distribution and composition of intramuscular fat in Duroc Jersey and Hampshire pigs at 100 kg liveweight

The intramuscular fat content, its fatty acid composition and that from the triglyceride fraction, were determined in several muscles from the right sides of four Duroc Jersey and four Hampshire castrated male pigs slaughtered at 100 kg liveweight. The Hampshires had heavier muscles than the Duroc Jersey pigs, but did not show significant differences in the percentages of intramuscular fat. The concentrations of linoleic acid were, in general, higher in the Hampshire than in the Duroc Jersey pigs and in many muscles the differences were highly significant (p < 0·05) The concentrations of linoleic acid (18:2) in the triglyceride fraction did not differ among muscles within breeds but were higher in Hampshire than in Duroc Jersey pigs.     

玉山黑猪肉营养特性分析

研究在优质肉生产中科学利用玉山黑猪这一优良地方猪种资源.对9头玉山黑猪的背最长肌中肌内脂肪、氨基酸、肌苷酸以及脂肪酸和背脂中的脂肪酸,从营养学角度进行分析评价.结果表明:玉山黑猪背最长肌中17种氨基酸总含量为19.16％,其中鲜味氨基酸和必需氨基酸占总氨基酸的比例分别为38.96％和44.78％,具有较浓的鲜味和较高的蛋白质“生物效价”,而且氨基酸评分结果表明玉山黑猪的必需氨基酸比例适宜,有利于人体吸收;玉山黑猪肉中肌内脂肪、肌苷酸含量分别为6.62％、2.99％,是其肉质鲜嫩多汁的物质基础;此外,玉山黑猪背最长肌和背脂的不饱和脂肪酸的比例都较高,其背最长肌亚油酸和亚麻酸的含量分别为12.73％和0.86％,表明玉山黑猪脂肪酸的营养价值比较高.     

安福火腿游离脂肪酸、风味物质及氨基酸分析

为揭示安福火腿的品质特性及其主体挥发性风味物质成分,采用气相色谱-质谱联用、固相微萃取-气相色谱-质谱联用等对其肌内脂肪和皮下脂肪中游离脂肪酸、挥发性风味物质进行对比分析及肌肉中氨基酸的组分含量进行定量检测。结果表明,从肌内脂肪和皮下脂肪中分别检测出19、29种游离脂肪酸（皮下脂肪的总游离脂肪酸含量是肌内脂肪的7.992倍）,29、31种挥发性风味物质。采用气味活性值分析法分别得到7、14种主体挥发性风味物质,其中己醛、辛醛、壬醛、（E, E）-2, 4-癸二烯醛和双戊烯是肌内脂肪和皮下脂肪中共同呈现的关键挥发性风味物质,3-甲硫基丙醛和癸醛仅存在于肌内脂肪中。肌肉中检测出17种氨基酸,且必需氨基酸的含量丰富,占氨基酸总量的41.98%,天冬氨酸和谷氨酸两种鲜味氨基酸的含量最高,它们对安福火腿的鲜美度有着重要的贡献。此研究可为后期分析加工工艺对安福火腿品质的影响提供借鉴。     

Composition of Bovine Muscle Lipids at Various Carcass Locations

SUMMARY— Bovine intramuscular lipids extracted from the semitendinosus, triceps brachii and longissimus dorsi muscles were fractionated into phospholipids and neutral fats by silicic acid column chromatography. In spite of the wide range in total fat content at each location, phospholipids were present in all three muscles at a level of approximately 500 mg per 100 g of muscle tissue. This result, coupled with the lower total fat content of the semitendinosus as compared to the other two muscles, indicated a significantly higher percentage of phospholipid material in the total fat from the semitendinosus as compared to the triceps brachii or longissimus dorsi.
The fatty acids were identified in both lipid fractions using retention time data obtained on both a polar and a non-polar column. The identity of the unsaturated fatty acids was confirmed when their peaks did not appear on the chromatographs obtained from brominated samples. There was significantly more C14:0 in the longissimus dorsi neutral fat fractions than in the semitendinosus neutral fat fractions. In the phospholipids, there was significantly more C16:0 and significantly less C18:0 in the longissimus dorsi as compared to either the semitendinosus or triceps brachii. Although the two lipid fractions of the longissimus dorsi contained slightly higher percentages of total saturated fatty acids than the corresponding fractions in the other two muscles, the effects were not significant.     

鲐鱼不同部位的营养评价及风味物质分析

本文以鲐鱼为研究对象,分析了鲐鱼不同部位(背肉、腹肉及尾肉)的基本成分、总氨基酸组成及脂肪酸组成,并对其营养价值和风味物质进行了分析。研究表明:不同部位中腹肉脂肪含量最高,为4.2%,背肉含量最少;尾肉蛋白质含量最低,仅为71.26%。总氨基酸组成差异不显著,其中各部位含量最高的氨基酸都为谷氨酸,含量达2.68 g/100 g。背肉中脂肪酸种类最多33种,尾肉最少为26种,各部位中DHA和EPA含量都很高。电子鼻结果表明三个部位的挥发性成分存在差异。背肉中检测出挥发性成分31种,腹肉、尾肉分别为32种和25种;背肉与腹肉中的游离氨基酸含量差异不显著,但和尾肉差异显著。背肉中核苷酸总量显著高于其他2个部位;三个部位都是IMP含量最高,分别为452.71、441.33、448.26 mg/100 g。研究结果将对鲐鱼肉的分类加工及深加工提供一定的参考价值。     

Effect of breed-type on the relationships between intramuscular and total body fat in steers

The partitioning of total dissectible body fat and the amounts of intramuscular fat in Psoas major, Semitendinosus and Biceps brachii muscles were determined in two groups of A. Angus and AA × Nelore steers with similar averages of total dissectible fat (27·7 kg). In addition, the fatty acid composition of total fat and the triglyceride fraction from dissectible and intramuscular fats were determined.

The AA × Nelore steers have higher levels of subcutaneous fat and lower levels of intermuscular fat than the A. Angus but contain lower levels of intramuscular fat in the three muscles. The allometric regressions varied according to the muscle and breed type. The fatty acid composition of subcutaneous and kidney fats were similar but differences in the percentages of 14:0, 18:0, 18:2 and 20:4 fatty acids in intramuscular fats between the two genetic groups were detected.     

Chemical fat composition of muscles of the indigenous Nigerian pigs as influenced by age and sex

Seven selected muscles of 96 indigenous Nigeria (32 female, 32 castrated male and 32 intact male) pigs aged between birth and 504 days were analysed for chemical fat. Highly significant age effects were observed for the seven muscles. Statistically significant sex differences were observed for all the muscles except semitendinosus. Generally, fat values for muscles of intact male pigs were lower than for the other two sexes. While non-significant sex-age interactions were observed for biceps femoris, semitendinosus, semimembranosous and longissimus dorsi muscles, highly significant effects were observed for psoas major, triceps brachii and infraspinatus. Growth coefficients b derived from log-log regressions of intramuscular fat weight on body weight ranged from an average of 1·088 (R(2) = 0·956) for M. infraspinatus to 1·348 (R(2) = 0·934) for M. biceps femoris and from 0·604 (R(2) = 0·945) to 0·756 (R(2) = 0·941) when related to carcass fat. Average growth coefficients for fore limb muscles were less than for hind limb and spinal column muscles. Fat growth in other depots is reported for comparison with growth of intramuscular fat.     

The effect of production system and age on concentrations of fatty acids in intramuscular fat of the longissimus and triceps brachii muscles of Angus-cross heifers

The concentrations of fatty acids were measured in intramuscular fat from the longissimus lumborum (LL) and triceps brachii (TB) muscles of Angus-cross heifers finished either on a high-concentrate ration in Washington, USA, (US cattle, n = 15) or on pasture in New Zealand (NZ cattle, n = 16). Half of the NZ cattle were of a similar age to the US cattle (NZAge) and half were of a similar weight (NZWt). Intramuscular fat levels were higher for the LL muscle and for the US cattle but only within the LL muscle (P < 0.05). Aspects of the fatty-acid patterns that are of relevance to human nutrition tended to favour the pasture-finished NZ cattle with lower n − 6/n − 3 fatty acid ratios (P < 0.001), higher concentrations of an anticarcinogenic conjugated linoleic acid (C18:2 c9,t11) (P < 0.05) and its precursor (trans-vaccenic acid, TVA) (P < 0.01), and lower levels of the 18-carbon trans monounsaturated fatty acids other than TVA (P < 0.01). Concentrations of 20 of the 22 fatty acids analysed differed significantly between the two muscles. When values were adjusted to a common intramuscular fat level by covariance, most of the group differences remained, but a number of the muscle differences became non-significant. For almost half the fatty acids considered, there was a significant interaction between treatment group and muscle, which indicates that the results for one muscle do not necessarily apply to other muscles, although the ranking of the groups was usually the same for both muscles.     

The influence of fibre-type composition and associated biochemical characteristics on the acid buffering capacities of several beef muscles

Several beef forequarter muscles were investigated for fibre-type composition, total pigments, total nitrogen, non-protein nitrogen, anserine, carnosine and inorganic phosphorus contents, ultimate pH (pH(u)) and acid buffering capacities. In general, the predominantly 'red' fibre-type muscles had significantly higher (P<0·05) pH(u) values and total pigment concentrations than the predominantly 'white' fibre-type muscles which had significantly higher (P< 0·05) total nitrogen, non-protein nitrogen and carnosine contents and also significantly higher (P< 0·05) acid buffering capacities. The relationships between the various biochemical parameters of all the muscles studied and their acid buffering capacities were investigated by correlation matrix. The higher buffering capacities of the 'white' fibre-type muscles over the pH range pH(u) to pH 5·0 were attributed to their higher contents of carnosine and inorganic phosphorus. However, over the pH ranges pH(u) to pH 4·5 down to pH(u) to pH 3·0, the higher buffering capacities of the 'white' fibre-type muscles were attributed primarily to their higher lactic acid concentrations, as indicated by their low pH(u) values, and also to their higher non-protein nitrogen contents.     

Oxidative and lipolytic deterioration of different muscles from free-range reared Iberian pigs under refrigerated storage

Three different type of muscles, two glicolytic (Serratus ventralis and Longissimus dorsi) and one oxidative (Masseter) were displayed under refrigeration at +4?°C during 10 days to evaluate differences in lipolytic and oxidative changes of different muscles with different metabolic pattern. Thiobarbituric acid reactive substances (TBARS), phospholipid content, hexanal content and fatty acid profiles of neutral and polar lipid fractions were analysed at day 0 and day 10. Phospholipid content (g phospholipids/g intramuscular fat) significantly (P<0.035) decreased from day 0 to day 10 in m. Masseter (0.33 vs. 0.25, respectively), but not in m. L. dorsi (0.12 vs. 0.09, respectively) and m. S. ventralis (0.19 vs. 0.14, respectively). Changes in fatty acid profiles of neutral and polar lipids significantly differed among muscles after storage. Slight differences were found in neutral lipids from m. L. dorsi and m. S. ventralis, while neutral lipids from m. Masseter were highly altered. Great changes affected fatty acid profiles from polar lipids in the three muscles. m. Masseter muscle showed significantly higher (P<0.000) TBARS values (1.13, 0.65 and 0.60 mg MDA/kg meat, respectively) and hexanal content (689.2, 241.2 and 355.8 μg/g meat, respectively) than m. L. dorsi and m. S. ventralis. In conclusion, oxidative meat is more prone to oxidative and lipolytic deterioration than glycolytic muscles during refrigerated storage and as a consequence of that a lower shelf-life.     

Fat content and fatty acid pattern in muscle and adipose tissue from differently reared calves

Two groups of Simmental calves were fed a milk replacer diet or were early weaned and slaughtered at the age of 4 months. Two muscles and two adipose tissue samples were removed, the lipids were extracted by chloroform-methanol and the fatty acid composition was analyzed by gas chromatography after transesterification with Na-methylate. Total lipid contents in both muscles were relatively small (<2%) Due to high phospholipid content, veal muscle lipids contain a high proportion of polyene fatty acids which accounted for more than 30%. Adipose tissue consists predominantly of oleic acid (from 34% to 37%) and palmitic acid (from 27% to 29%). In extractable perinephric fat, milk replacer diet caused significantly higher myristic acid (C(14)) values and, accordingly, lower oleic (C(18:1)) values.     

Carcass composition and meat quality of three different Iberian×Duroc genotype pigs

Carcass composition and meat quality of Longissimus dorsi (LD) and Biceps femoris (BF) muscles from three different Iberian×Duroc genotype pigs were studied: GEN1: ♂ Iberian×♀ Duroc1; GEN2: ♂ Duroc1×♀ Iberian; GEN3: ♂ Duroc2×♀ Iberian. Duroc1 (DU1) were selected for the manufacture of dry-cured meat products while Duroc2 (DU2) were pigs selected for meat production, with high percentages of meat cuts and low carcass fat. Genotype had a significant effect on the differences found while sex had not. GEN2 showed the highest weights at days 180 and 238 of weaning and the highest slaughter weights (day 316) followed by GEN3, while the lowest weights were found in GEN1. GEN3 had well conformed carcasses in comparison with GEN1 and GEN2, since GEN3 showed the highest percentages of ham and loin and the highest weight of loin as well as the lowest back and ham fat thickness. However, the use of DU2 pigs in the cross with Iberian had negative effects on meat quality, as GEN3 gave the worst meat quality in both muscles, postmortem pH, cook and drip loss, and colour and the lowest percentages of intramuscular fat (IMF). In subcutaneous fat (SCF), GEN3 had higher percentages of polyunsaturated fatty acids (PUFA) than GEN2, while GEN2 had higher saturated fatty acids (SFA) levels. In LD, IMF from GEN3 showed the highest percentage of MUFA and PUFA; while the fatty acid profile of GEN2 was more saturated. BF muscle showed similar trends, but not significantly so. On the other hand, few differences were found between reciprocal crosses (GEN1 vs. GEN2). GEN2 showed higher IMF in LD than GEN1, agreeing with their carcass weight. As a result, GEN1 had a fatty acid profile of IMF in the LD that was more unsaturated.     

Nutrient composition of Najdi-camel meat

The proximate composition, amino-acid composition, and inorganic nutrients of different wholesale cuts and organs of 18 (six each at eight, 16, and 26 months) Najdi male camels have been determined. Skeletal muscles contained 68·8-76% moisture; 19·4-20·5% protein; 4·1-10·6% fat, and 1·0-1·1% ash. In proximate composition, camel meat is generally similar to beef. Significant differences (p < 0·05) in moisture, fat, potassium, sodium, magnesium, iron, and zinc were found between samples. The meat protein tended to have a higher percentage of the amino acid proline than literature values for other red meats, and lower values for tryptophan, aspartic acid, and tyrosine. Differences were observed between skeletal muscles and organs in nutrient content. Organs have higher percentages of ash, sodium, and iron than skeletal muscles. Among organs, kidneys contained higher quantities of moisture, calcium, and sodium but lower values of protein, magnesium, and potassium than liver and heart meats.     

Intramuscular fatty acid profile of longissimus dorsi and semitendinosus muscle from Pateri goats fed under traditional feeding system of Sindh, Pakistan

The present study was undertaken to assess the intramuscular fatty acid composition of different muscles taken from male Pateri (n=15) goats, reared on naturally grown grasses, leaves and pods of Acacia nilotica and crushed cereal, under traditional way of feeding. Goats were slaughtered with an average weight of 68±7kg and age 12±1 month. The samples were taken from longissimus dorsi region (between the 12th and 13th rib) and distal region of semitendinosus muscle. Results of total fat content and fatty acids composition does not show significant (P>0.05) variation among muscles investigated. The fatty acid composition of muscles studied were primarily composed of oleic (31.50-33.38%), followed by palmitic acid (19.84-22.05%) and stearic acid (22.25-24.91%) respectively. Muscle tissue in general contained an average 51.13% of saturated fatty acids and 48.87% of unsaturated fatty acids. The mean conjugated linoleic acid was found 0.41%, 0.43% and 0.47% in ribeye and loin portion of longissimus dorsi muscle and distal region of semitendinosus muscle, respectively.     

2 种低值金枪鱼赤身肉的营养成分分析与评价

以青干金枪鱼和鲔的赤身肉为研究对象,通过气相色谱、液相色谱和原子吸收光谱等理化检测方法对其进行营养成分分析并作出评价。结果表明：1）青干金枪鱼和鲔赤身肉水分含量分别为71.13%和72.27%;粗脂肪含量分别为0.63%和1.47%;粗蛋白质含量分别为24.56%和23.44%;灰分含量分别为1.56%和1.38%;2 种金枪鱼均含有丰富的矿物质元素。2）青干金枪鱼和鲔赤身肉多不饱和脂肪酸含量高,尤其是二十二碳六烯酸含量高达28.53%和21.56%。3）青干金枪鱼和鲔赤身肉氨基酸配比合理,必需氨基酸/总氨基酸分别为39.86%和39.97%,必需氨基酸指数分别为96.23和96.66。因此,2 种金枪鱼赤身肌肉蛋白含量高,脂肪含量低,具有较高的营养价值。     

2 种不同品系中华鳖的营养成分分析与比较

以清溪花鳖和中华鳖日本品系为研究对象,对鳖雌雄肌肉和裙边水分、粗蛋白、粗脂肪、灰分、矿物质元素含量及氨基酸、脂肪酸组成进行分析。结果表明：1）清溪花鳖和中华鳖日本品系雌雄肌肉的粗蛋白含量分别为18.46%、17.25%、19.17%、18.83%,裙边为21.00%、22.31%、24.89%、20.07%,2 种鳖雌雄肌肉的粗脂肪含量分别为1.07%、0.96%、1.17%、1.05%,裙边为0.23%、0.32%、0.30%、0.27%;2）清溪花鳖和中华鳖日本品系雌雄肌肉的必需氨基酸指数分别为93.92、92.52、91.89、93.12,说明2 种中华鳖的肌肉营养丰富,均为良好蛋白源,肌肉中必需氨基酸/氨基酸总量分别为37.10%、36.67%、36.48%、36.76%,裙边中必需氨基酸/氨基酸总量分别为17.74%、19.73%、17.80%、17.81%;3）清溪花鳖和中华鳖日本品系雌雄肌肉中多不饱和脂肪酸含量丰富,二十碳五烯酸＋二十二碳六烯酸的含量分别为14.98%、13.97%、16.20%、19.22%,中华鳖日本品系雌雄肌肉中二十碳五烯酸＋二十二碳六烯酸的含量要高出清溪花鳖约3%。     

LIPID COMPOSITION OF BOB AND SPECIAL-FED VEAL

Four muscles were studied to determine the lipid composition of Bob (BV) and Special-fed (SFV) veal. No differences existed for proximate analysis values of muscles from carcasses of different weight classes (P> 0.05). Muscles from SFV were higher in fat (P < 0.05) and generally displayed more protein and less moisture than the BV. BV contained more cholesterol than SFV (P< 0.001); however, there was no difference among the 4 muscles for cholesterol content (P > 0.05). SFV contained more 14:0 and 18:2, and less 16:1, 18:0 and 18:1 fatty acids than BV (P< 0.05). Fatty acid composition on a g per 100 g tissue weight basis was higher in 14:0, 16:0, 17:0, 18:2 and 20:4 (P< 0.05) for SFV. The longissimus contained more 14:0, 16:0, 18:0 and 18:1 than the other muscles studied (P< 0.05). The results indicate that veal is an appropriate low-fat muscle food which meets modern dietary guidelines concerning fat consumption.