不同品种鸡蛋品质及蛋黄中热量和性激素含量的比较

为研究不同品种鸡蛋品质及蛋黄中热量和性激素含量,该试验以遂昌散养土鸡所产的鸡蛋、市售散装土鸡蛋和普通鲜鸡蛋为研究对象,测定鸡蛋重量、蛋黄干湿重和热量以及蛋黄睾酮、二氢睾酮和雌二醇等性激素含量。结果表明,市售散装土鸡蛋和普通鲜鸡蛋的重量显著大于遂昌土鸡蛋（P〈0.05）,而遂昌土鸡蛋与散装土鸡蛋的蛋黄干湿重和热量均显著高于普通鲜鸡蛋（P〈0.05）;遂昌土鸡蛋蛋黄睾酮和二氢睾酮含量均显著低于散装土鸡蛋和普通鲜鸡蛋（P〈0.05）,而蛋黄雌二醇含量在3种鸡蛋中无显著差异（P=0.145）。     

红曲霉-中药复合制剂对鸡蛋营养品质和胆固醇含量的影响

本研究旨在探讨红曲霉-中药复合制剂对鸡蛋营养品质和胆固醇含量的影响.试验测定了鸡蛋的蛋白、蛋黄、水分、蛋白质、脂肪以及胆固醇等指标.结果表明,鸡蛋蛋白和蛋黄含量、含水量、蛋白质及脂肪含量未见显著差异(P＜0.05),试验第7周时,与对照组相比,试验组全蛋和蛋黄中胆固醇含量(mg/g)明显降低(P＞0.05).     

饲料营养成分对鸡蛋品质的影响

鸡蛋的品质主要涉及蛋重、蛋壳质量、蛋黄色泽、蛋的成分与风味等。许多研究表明,饲料中多种营养成分影响蛋的品质。1　饲料营养成分对鸡蛋成分的影响近30年来,鸡蛋因蛋黄中含较高的胆固醇而消费呈下降趋势。遗传育种方法至今还未能成功降低鸡蛋蛋黄中胆固醇的含量,而营养学上有些研究发现,饲料中的某些微量成分能起到调控鸡蛋胆固醇含量的作用。Pesti和Bakalli( 1 998)试验研究表明,日粮添加1 2 5mg/kgCu2 +,蛋黄中胆固醇从1 1 7mg/g下降至8 6mg/g ,降低了2 6% ;添加2 5 0mg/kgCu2 +则蛋黄胆固醇进一步下降到7 9mg/g。有研究表明,β-环…     

基于包装正面(FOP)标签方案的生鲜鸡蛋营养价值评价

为推动我国生鲜鸡蛋包装正面(FOP)标签方案落地实施,笔者借鉴国外经验,基于《中国食物成分表》(标准版第6版第2册)和《食品安全国家标准预包装食品营养标签通则》数据,比较5种生鲜鸡蛋[普通白皮鸡蛋、土鸡蛋、普通红皮鸡蛋、藏鸡蛋、乌鸡蛋(绿皮)]的可食部分能量与主要营养成分含量,采用富含营养素食物(NRF)9.3模型评价5种生鲜鸡蛋的营养价值,并采用评分法对5种生鲜鸡蛋进行营养评分,用于FOP标签设计,探索合适的FOP标签方案。结果表明：5种生鲜鸡蛋的可食部分能量均在120～150 kcal(每100 g鸡蛋,1 kcal=4.186 kJ)之间,相差不大;土鸡蛋的胆固醇含量高达1 177.4 mg(每100 g鸡蛋),是普通鸡蛋的2倍;5种生鲜鸡蛋的饱和脂肪酸含量均不足10 g(每100 g鸡蛋),钠含量均不高,均属于低钠食品,蛋白质含量均高于10 g(每100 g鸡蛋);5种生鲜鸡蛋的维生素A含量均在200μg(每100 g鸡蛋)以上,其中普通白皮鸡蛋是富含维生素A的鸡蛋[维生素A含量≥240μg(每100 g鸡蛋)]。5种鸡蛋的NR9_{100 kcal}值相差较小...     

低胆固醇沙棘鸡蛋的品质和营养成分分析

本试验通过测定低胆固醇沙棘鸡蛋的蛋品质、营养成分、类胡萝卜素含量、胆固醇含量,并和普通鸡蛋进行比较分析。结果表明,沙棘鸡蛋的蛋黄颜色(罗氏色泽)、蛋黄比例、蛋黄/蛋清比例、蛋重较普通鸡蛋分别提高了26.21%、16.00%、48.72%、10.54%(P 0.05),2种鸡蛋的哈夫单位数值均在72以上,蛋比重为1.06～1.10、蛋壳厚度均在0.35 mm以上,且无显著性差异(P 0.05);沙棘鸡蛋的灰分含量、粗脂肪含量、蛋白质含量较普通鸡蛋分别提高了21.15%、26.59%、14.51%(P 0.05),并且其蛋黄和全蛋的类胡萝卜素含量较普通鸡蛋分别提高了85.81%、44.09%(P 0.01);沙棘鸡蛋蛋黄、蛋清以及全蛋胆固醇含量相对于普通鸡蛋降低了45.17%、71.31%、48.64%(P 0.01)。沙棘鸡蛋的营养价值、口感明显优于普通鸡蛋,蛋品质和等级也高于普通鸡蛋,类胡萝卜素含量的增加和胆固醇含量的降低提高了沙棘鸡蛋的保健作用,使营养丰富的鸡蛋又增加了自身的附加值。     

鸡 HMGCR 基因SNPs及其与鸡蛋胆固醇含量的关联性分析

为培育一种蛋黄胆固醇含量较低的蛋鸡新品系,以丝羽乌骨鸡为研究对象,测定675枚丝羽乌骨鸡蛋蛋黄胆固醇含量,通过DNA测序技术和创造酶切位点PCR-RFLP方法检测了丝羽乌骨鸡群体中3-羟基-3-甲基戊二酸单酰辅酶A还原酶基因的2个SNPs位点,分别分析这两个SNPs位点不同基因型与鸡蛋胆固醇含量的关联性。结果表明:(1)丝羽乌骨鸡蛋蛋黄胆固醇含量为13.41mg/g,鸡蛋中胆固醇含量为456.50mg/100g。(2)g.12217G>T位点中GG基因型的鸡蛋胆固醇含量最低,且与其他两种基因型具有显著的差异。     

加拿大鸡蛋中胆固醇含量的调查

在加拿大市售的自来航鸡蛋中胆固醇含量究竟有多少,为此进行了调查。在全国各地随机选择14个蛋鸡场,收集27～52周龄期间产出的鸡蛋(每个场8～12枚)。用高效液相色谱仪分析鸡蛋中胆固醇的含量。测定结果,每克蛋黄中胆固醇的含量为12～15mg之间,平均13mg。每个鸡蛋(平均蛋重60.4士5g)的胆固醇含量在139～288mg之间,平均221±29mg。大型蛋(56～64g)的胆固醇含量平均为     

利用酶法简捷测定鸡蛋总胆固醇含量研究

本文利用商品血清胆固醇试剂盒(酶法)建立了一种快速、简单、准确测定鸡蛋总胆固醇含量的方法。取全蛋液约500 mg(蛋黄液约200 mg)用5 000μL乙醇旋涡振荡提取1 min,离心10 min(10 000 r/min),取200μL上清夜与2 000μL测定试剂混匀,37℃保温10 min,测定500 nm的吸光值。本方法线性范围为0～120μg胆固醇,测定极限约0.40μg、0.15μg,在1 h内可以测出鸡蛋胆固醇含量。利用本文建立的方法对3种鸡蛋胆固醇含量进行了测定,每克可食部分含量为3.88～3.95 mg,每枚含量范围为198.9～210.1 g,平均为206.4 mg。     

六种不同来源鸡蛋胆固醇含量的测定和比较分析

为了解不同来源鸡蛋胆固醇含量并降低其含量,试验采用邻苯二甲醛分光光度计比色法测定了蛋黄中胆固醇的含量。结果表明:胆固醇在550nm处有最大吸收峰;超市6种不同来源(北京、江西、湖南、乌鸡、始兴和土大妈)的鸡蛋蛋黄平均胆固醇含量分别为17.43,16.56,13.80,12.50,13.85,11.74mg/g,经方差分析和多重比较,不同来源样品间含量存在差异。测定的加样回收率为99.41%,测定的样品标准差和变异系数分别为0.23mg/g、1.97%,显示试验的准确性高,重复性好。不同来源样品间比较分析认为,品种、营养、饲养管理条件等可能是导致胆固醇含量存在差异的主要原因。     

不同苜蓿草粉水平对产蛋鸡蛋黄胆固醇含量影响的研究

选择健康35周龄新罗曼商品代蛋鸡768只,采用2×4因子试验设计,随机分为8个处理组,每组3个重复,每个重复32只,分别在饲粮中添加0,3%,5%,7%的紫花苜蓿草粉和1.6%和2.4%的油脂,试验期60 d,观测苜蓿草粉和油脂对鸡蛋蛋黄重、蛋黄相对重、每克蛋黄胆固醇含量以及每枚鸡蛋中胆固醇含量的影响.结果表明:1)添加苜蓿草粉和油脂后,对蛋黄相对重无显著影响(P＞0.05);蛋黄重有显著增加,其中低油脂组中7%草粉添加组蛋黄重极显著高于不添加组(P＜0.01),各添加组之间差异不显著;高油脂组中各添加组之间无显著差异;每g蛋黄胆固醇含量有较大降低,添加草粉后,各试验组较不添加组极显著降低每g蛋黄中胆固醇含量(P＜0.01);每枚蛋中胆固醇含量有显著降低,其中高油脂组中5%和7%草粉添加组蛋黄重极显著高于不添加组(P＜0.01),各添加组之间差异不显著.二者的交互作用中,苜蓿水平对鸡蛋中胆固醇的影响高于油脂水平.2)随着苜蓿草粉添加水平的增加,每g蛋黄中胆固醇含量和鸡蛋中胆固醇含量逐渐降低,每g蛋黄中胆固醇含量在前30 d下降较快,随后逐渐降低,试验至45 d时趋于平稳.     

鸡蛋胆固醇含量测定方法比较研究

试验随机选取了中华绿蛋鸡产的绿壳蛋和依莎褐蛋鸡产的褐壳鸡蛋各20枚,采用邻苯二甲醛分光光度计比色法和气相色谱法,测定鸡蛋中胆固醇的含量,比较两种方法在测定鸡蛋胆固醇含量上的差异。结果表明,用邻苯二甲醛比色法测得褐壳蛋蛋黄胆固醇含量176．79mg／枚,浓度为13．35mg／g。用气相色谱法测得胆固醇含量142．74mg／枚,浓度为9．69mg／g,二种方法测定的结果差异显著（P〈0．05）。用邻苯二甲醛比色法测得绿壳蛋蛋黄胆固醇含量158．12mg／枚,浓度为10．65mg／g。用气相色谱法测得胆固醇含量128．70mg／枚,浓度为8．54mg／g,二种方法测定的结果差异显著（P〈0．05）。     

Effects of Egg Yolk Source on the Cryopreservation of Stallion Spermatozoa

Three experiments were conducted to determine whether replacement of chicken egg yolk, as a component of freezing extenders, with egg yolk from other avian species would improve the post-thaw motility and percentage of intact acrosomes of stallion spermatozoa. In the first experiment, substitution of chicken egg yolk with chukar egg yolk, as a component of the lactose-ethylenediaminetetraacetic acid extender, improved (P ≤ .05) the post-thaw motility of stallion spermatozoa. These results were not replicated in (IMV Technologies, Maple Grove, MN, USA) a more expansive study comparing 2%, 4%, 6%, or 8% egg yolk combined with INRA 96 when a “slow freeze” method was used, or the same substitution at levels ranging from 13% to 22% when egg yolk was combined with lactose-ethylenediaminetetraacetic acid for diluents used for a “fast freeze” method of cryopreservation. In the third study, egg yolks from regular and high omega-3 chicken eggs as well as from turkey, chukar, and mallard duck eggs were analyzed for lipid content and fatty acid profile. The yolk from the turkey eggs was higher (1,300 mg/100 g) and that from mallard ducks was lower (560 mg/100 g) in cholesterol as compared with the two types of chicken eggs and chukar egg yolk (range, 1,046-1,094 mg/100 g). In addition, the high omega-3 eggs did test higher for fatty acids (4.51 g/100 g) than other types of eggs (range, 0.28-0.73 g/100 g). Substitution of chicken egg yolk with turkey, but not duck, egg yolk resulted in higher post-thaw total motility (P ≤ .05) for spermatozoa obtained from two of the three stallions used in the third experiment.     

Correlations between breeder age, egg cholesterol content, blood cholesterol level and hatchability of broiler breeders

1. The research was carried out to investigate correlations between breeder age, egg cholesterol content, blood cholesterol level and hatchability of broiler breeders. 2. Egg cholesterol content increased with increased breeder age. The mean yolk cholesterol contents (mg per g yolk) were 10.47+/-0.28, 15.34+/-0.65 and 15.64+/-0.71 mg/g at 28, 45 and 65 weeks of age, respectively. 3. There were positive correlations between yolk weight and yolk cholesterol content (mg/g yolk) (r=01.941; P<0.01) and egg cholesterol content (mg/egg) (r=0.980; P<0.01). 4. Negative correlations were found between egg yolk cholesterol content and hatchability of fertile eggs (r=-0.345; P<0.05), fertility ratio (r=-0.609; P<0.01) and hatchability of total eggs (r=-0.574; P<0.01). 5. The mean blood cholesterol levels were 165.1+/-11.04, 166.5+/-11.97 and 179.5+/-11.33 mg/dl at 28, 45 and 65 weeks of age, respectively.     

Effect of dietary saffron (Crocus sativus L.) on the oxidative stability of egg yolk

1. The effects of dietary inclusion of red stigmas of Greek saffron (Crocus sativus L.) on the oxidative stability of shell eggs and liquid yolks were investigated and compared with those of dietary a-tocopherol. 2. Ninety-six Lohmann laying hens, 38 weeks old, distributed into 4 groups with 4 replicates each, were given either a control diet, diets enriched with 10 (SAF10) or 20 (SAF20) mg/kg saffron, or a diet enriched with 200 mg/kg a-tocopheryl acetate (VE200). 3. Following 6 weeks of feeding, eggs were collected and the rate of lipid oxidation was determined in refrigerated stored shell eggs, as well as in yolks adjusted to a pH of 6.2 or 4.2 and stored in the presence of light. 4. The results showed that the extent of lipid oxidation in shell eggs, as measured by malondialdehyde (MDA) formation, differed between dietary treatments, but did not change with storage time. In stored shell eggs, MDA levels differed between dietary treatments at all time points. 5. Yolks from the control group adjusted to pH 6.2 gave MDA values higher than those of the SAF10 group, which in turn were higher than those of the SAF20 group, a finding suggesting that saffron exerted a dose-dependent antioxidative activity. The VE200 group gave lower MDA values than the other groups at all time points. The oxidation profile of yolks at pH 4.2 showed a similar pattern but the rate of oxidation was greater.     

Divergent selection for yolk cholesterol in laying hens

1. Lines were selected for divergence in yolk‐cholesterol concentration for three and four generations in the Cornell Control (Leghorn) and Athens‐Canadian (AC) (meat‐type) randombred populations respectively. Selection was based on both individual and family records.

2. Cholesterol values were obtained from two consecutively laid eggs when birds were 28 weeks of age. The yolks of eggs from individual hens were pooled and analysed for cholesterol content by the colorimetric assay of Zlatkis et al. (1953) on the “fat extract” obtained by a modification of the procedure of Folch et al. (1956).

3. The largest differences between high and low lines (1.lb27 and 1.lb38 mg cholesterol/g yolk) were observed in the last generation of selection. There was evidence of a lack of response in the low lines. Realised herita‐bility estimates obtained by dividing the difference between high and low lines by half the cumulative selection differential ranged from 0.lb11 to 0.lb25 in the AC population and from 0.lb21 to 0.lb25 in the Leghorn population. Realised estimates on a within‐line basis suggest that selection for yolk cholesterol is effective only in the upward direction.     

Physiological performance of quails that underwent dietary and pharmacological manipulation of cholesterol

The present work evaluated whether dietary and pharmacological interference on cholesterol synthesis were capable of inducing alterations in blood and yolk cholesterol levels and the secretion of corticosterone metabolites. Forty‐five 40‐day‐old quails were divided into three experimental groups: vegetal fat diet, 2% beef fat (tallow) diet and vegetal fat diet with simvastatin administration (3.13 mg/kg/day). During all experiments, the animal weights and food consumption were recorded and blood and faecal samples (days 0, 15, 30, 45 and 60), as well as eggs (days 30, 45 and 60), were collected. Analysis of serum and yolk cholesterol was performed and faecal corticosterone levels were measured. No differences were observed on blood cholesterol or faecal corticosterone between all treatments, despite a tendency of increased cholesterol in the group with the animal fat diet. However, quails submitted to an animal fat diet displayed an increase in yolk cholesterol at day 30 of the treatment and the egg yolks of quails treated with simvastatin exhibited a decrease in cholesterol content by the end of the treatment at 60 days. These results improved the knowledge regarding the physiology of quails and offered support to other studies concerning the consequences of the pharmacological treatment and the dietary manipulation of cholesterol levels.     

Chromatographic analysis of lypophilic compounds in eggs from organically fed hens

Egg yolks represent a common foodstuff in the human diet and are an important source of nutrients including lipids and carotenoids. The aim of this study was to compare the carotenoid, fatty acid and vitamin E contents of the yolk of eggs from nine hen breeds (Barred Plymouth Rock, Speckled Italian, Black Italian, Red Italian, Rhode Island, Silver Laced Wyandotte, Gold Araucana, Partridge Brahma and Yellow Cochin) raised in barns in an enclosed house. Gas chromatography-mass spectrometry (GC-MS) was used for the fatty acid analyses, and reversed phase-high performance liquid chromatography-photodiode array detection (RP-HPLC-PDA) for carotenoids and vitamin E quantification. The major carotenoids identified were lutein and zeaxanthin, which together represented more than 93% of the total carotenoids, followed by β-cryptoxanthin and β-carotene.The results indicated that the total carotenoid content of the eggs ranged from 16.84–87.31 μg/g egg yolk (average value 49 μg/g egg yolk). The most representative fatty acids found were palmitic acid, stearic acid, oleic acid and linoleic acid. Significant differences in the proportions of α-linolenic acid were observed among the samples. The α-tocopherol content was directly correlated with the total carotenoid content. The results show that the chemical composition of egg yolk varies greatly among hen breeds.     

Egg yolk fatty acid profile of avian species – influence on human nutrition

Lipids are an important nutritional component of the avian egg. A review of the literature was completed to determine the fatty acid compositions in egg yolk from some avian species. Additionally, the nutritional influence of lipid and lipoprotein content on the plasma of male participants during 30‐day feeding was discussed. The ostrich eggs had the highest unsaturated fatty acid and the lowest cholesterol content in relation to other avian species. Ostrich had a higher proportion of 18:3n‐3 (p < 0.01) compared with other species. Chicken yolk numerically contained much higher levels of 22:6n‐3 than those found in turkeys, quails and geese, but the amount of 22:6n‐3 in ostrich egg was lower by comparison with other species (p < 0.01). After the storage of eggs at the room temperature, there was a notable loss of vitamin E (vitE) in the yolks of all species and this decrease was marginal (p < 0.01) in ostrich compared with other species. There were significant (p < 0.05) increases in plasma low‐density lipoprotein (LDL) level in all male subjects. Plasma high‐density lipoprotein (HDL) level decreased (p < 0.05) only in men who were fed chicken or ostrich eggs daily. Consumption of different species’ eggs had no influence on the total male plasma cholesterol and triglyceride levels. LDL‐C:HDL‐C ratio increased (p < 0.05) after goose and turkey egg consumption. Consumption of one egg/month by healthy human subjects had no effect on serum total cholesterol and triglyceride. The LDL‐C:HDL‐C ratio (which is a strong predictor of coronary heart disease risk) increased, although non‐significantly, by consuming chicken, quail and ostrich eggs.