Optimizing storage temperature of liquid bovine semen diluted in INRA96

Temperature regulation of liquid bovine semen can be difficult in field situations. Two experiments were carried out to assess the effect of storage temperature on in vitro sperm characteristics and 60-d nonreturn rate (NRR) following artificial insemination (AI) of liquid bovine semen. In experiment 1, the effect of storage of liquid bovine semen in INRA96 diluent (IMV Technologies, L'Aigle, France) at 1 of 5 storage temperatures (5, 15, or 28°C, and fluctuating between 5 and 15°C or 5 and 28°C) on total and progressive motility and kinematic parameters was assessed objectively via computer-assisted sperm analyzer on d 0, 1, 2, 3, and 4 after collection. Fluctuating temperatures were designed to mimic day- to nighttime variation. In experiment 2, we assessed the field fertility of liquid semen stored at a constant 5 or 15°C or in an unregulated manner and compared with that of frozen-thawed semen (total of n = 106,738 inseminations). In experiment 1, we detected a linear decrease in motility with increased duration of storage. Semen stored at a constant 15°C or fluctuating between 5 and 15°C had greater total motility than semen held at 5 or 28°C or fluctuating between 5 and 28°C; however, semen stored at 15°C and fluctuating between 5 and 15°C did not differ from each other. Semen held at a constant 5 or 15°C or fluctuating between 5 and 15°C, although not differing from each other, had higher progressive motility scores than that held at 28°C or fluctuating between 5 and 28°C. Semen stored at a constant 28°C exhibited poor motility and velocity values but had high progressive motion values compared with that all other storage temperatures; however, the other storage temperatures did not differ from each other in relation to motility kinematics. In experiment 2, semen stored at a constant 5°C resulted in a lower 60-d NRR (62.5%) than storage at constant 15°C or unregulated temperature or frozen-thawed semen (73.6, 74.6, and 74.4%, respectively. In conclusion, sperm stored in IRNA96 are quite tolerant in terms of storage temperature, retaining acceptable motility between 5 and 15°C. Storing semen at a constant 15°C resulted in greater in vitro sperm motility and higher NRR rates than storage at 5°C and did not differ in NRR from frozen-thawed semen or semen stored at an unregulated temperature; however, lower storage temperatures were shown to be more detrimental to sperm in vivo than unregulated storage conditions.     

大麻纤维高温煮练时间与脱胶质量的关系

大麻纤维具有无刺痒感、吸湿透气、抗静电、抗菌、屏蔽紫外线等优良性能,但大麻的纺织加工仍存在很多问题,传统的化学脱胶方法仍存在一定的局限性。通过对高温煮练前后大麻组分分析、电镜照片观察及强力指标的测试,探讨在其它因素不变的情况下,高温煮练时间变化对大麻纤维脱胶质量的影响。结果表明,在一定条件下最适合大麻纤维高温煮练的时间为3 h左右。     

Influence of extraction temperature on the final quality of espresso coffee

The final quality of espresso coffee (EC) depends upon certain technical conditions, such as the extraction temperature used in preparing it. The aim of this work was to investigate the effects of water temperature (88, 92, 96 and 98 °C) on the final quality of three types of EC (Arabica, Robusta Natural blend and Robusta Torrefacto blend) in order to select the optimal temperature. Volatile compound (analysed by Static headspace gas chromatography/mass spectrometry) and sensory flavour profiles were the most relevant parameters, whereas physicochemical, taste and mouthfeel parameters were not very useful for selecting the water temperature. For Arabica and Robusta Natural blend ECs, 92 °C was the optimal water temperature. For Robusta Torrefacto blend EC the overall acceptability might lead to the selection of 88 °C as the ideal water temperature, but the high percentages of key odorants related to roasty and earthy/musty flavours and the ‘not hot enough’ perception dictated the selection of 92 °C in this case as well. © 2003 Society of Chemical Industry     

原绒品质与纺纱质量

决定纱线质量的基础因素是原料质量.文章从配绒方面寻找原料指标与纱线指标之间的相关性.结果表明:原绒回潮率、强力、细度、巴布长度、短绒率等与成纱质量指标的相关性较大,影响成纱回潮率、强力、纱线线密度和捻度等重要指标.同时,分析了原料品质和温湿度、粗纺工艺流程之间的相关性,为提高纱线质量提供了理论依据.生产实践和理论分析中得出,原绒品质与工艺二者的主次关系,应根据具体情况和条件,以降低成本提高质量为中心,全面权衡.     

不同真空预冷终温对新鲜牛肉品质的影响

从宏观结构和微观结构等方面来探讨真空预冷（不同的预冷终温,2、4、6℃）与传统的预冷方式对新鲜牛肉品质的影响。结果表明,真空预冷后牛肉的失水率高于其他的预冷方式,且真空预冷的终温越低,失水率越高,不同的预冷方式对失水率差异性显著（p<0.05）。真空预冷的降温速度分别是-18℃冷库预冷和0℃冷库预冷的2倍和8倍左右。综合质构TPA指标、色差、蛋白质变性等理化指标,发现不同的预冷方式对牛肉均存在显著性差异（p<0.05）,除水分损失较大之外,真空预冷对牛肉品质的影响较小,其中真空预冷终温至4℃时较其他的预冷方式更接近新鲜牛肉的理化指标。结论:真空预冷作为一种快速的蒸发预冷技术适合于牛肉胴体的预冷。      

Effect of oven temperature profile and different baking conditions on final cake quality

This study discusses the effect of airflow on oven temperature profiles, the internal cake temperature and the final cake quality. It was found that the presence of airflow reduced the oscillation in the oven temperature profile from 12.98–30.27% to 3.17–4.02%. The bottom of the oven chamber experienced the greatest reduction in temperature oscillation in the presence of airflow. During the second stage of baking with airflow, the heating rate was increased from 5.07 to 7.52 °C min^?1 and 8.35 °C min^?1 to the increase of the baking temperature from 160 to 170 °C and 180 °C, respectively. The cake volume expansion rate was also increased 5–10% during second stage when baking with airflow condition. The cakes baked in the presence of airflow had a more porous crumb texture and lower moisture content compared to the cakes baked without airflow.     

The effect of muscle, cooking method and final internal temperature on quality parameters of beef roast

The aim of the study was to evaluate the influence of cooking conditions (dry air and steam) and final internal temperature (75, 85, 95°C) on the physico-chemical properties of beef infraspinatus (INF) and semimembranosus (SEM) muscles as well as their tenderness and juiciness. Cooking method and temperature influenced moisture, total collagen content in cooked meat and cooking loss, whereas muscle type affected fat, total collagen content and cooking loss. Warner-Bratzler shear force values were affected by cooking method, which also influenced juiciness of roasts. Temperature affected tenderness and juiciness, whereas muscle type influenced juiciness. The most desirable tenderness had INF heated in steam and dry air to 95°C. Processing SEM in dry air to 85 and 95°C lowered the juiciness of the roasts. There were significant correlations between physico-chemical, sensorial and image attributes, however high accuracy of prediction (r(2)>0.8) was achieved only for SEM muscle.     

再生季稻米蛋白质含量与外观、碾米品质及营养品质的关系

以10个不同品种再生季稻米为研究材料,探究再生季稻精米中蛋白质含量与矿物质元素、氨基酸含量、外观品质、加工品质的关系。结果表明：供试品种再生季稻米畾优1068的加工品质较差,外观品质较好,其精米中蛋白质、矿物质元素以及氨基酸酸含量最高。相关性分析表明蛋白质含量与Cu元素、甘氨酸、丙氨酸、脯氨酸、组氨酸、丝氨酸以及谷氨酸显著正相关（其中与丝氨酸、谷氨酸的相关系数分别达0.97和0.98）;与出糙率、精米率、垩白粒率、垩白度显著负相关。因此,Cu元素及丝氨酸、谷氨酸等含量的增加有利于蛋白质的积累;同时,蛋白质含量的增加会减少再生季稻米中的垩白,改善稻米的外观品质,但是会降低出糙率和精米率     

Effect of serum sources and colostral whey on bovine semen quality and spermatozoa immunoglobulin G immunofluorescence

Heifer, bull, fetal calf sera, and colostral whey were used to evaluate the influence of protein concentrations on percent progressive motility, head-to-head agglutination, acrosomal integrity, and immunoglobulin G immunofluorescence of bovine spermatozoa using ejaculates from 10 bulls. In the first experiment, 10% (vol/vol) addition of undiluted colostral whey resulted in the highest head-to-head agglutination, acrosomal integrity, and immunoglobulin G immunofluorescence. Ten percent (vol/vol) addition of whey diluted to a protein concentration equivalent to fetal calf serum produced significantly lower agglutination, acrosomal integrity, and immunoglobulin G immunofluorescence. Fetal calf serum was unable to produce agglutination and immunoglobulin G immunofluorescence of bovine spermatozoa. Heifer and bull sera produced similar responses for all seminal measurements. In Experiment 2, unheated whey and heifer serum resulted in higher response for all variables than heat inactivated whey and heifer serum. Whey treatment produced greater spermatozoal motility, agglutination, acrosomal integrity; and immunoglobulin G immunofluorescence than treatment with heifer serum. Spermatozoal immunofluorescence indicated antibodies in normal whey, bull, and heifer serum bound to spermatozoal membranes at the acrosomal region. Colostral whey was an effective source of agglutinin factor. Normal unheated whey and heifer serum did not cause sperm damage or immobilization.     

打叶质量与出片率的关系

为优化 12 0 0 0kg/h 4打 11分卧式打叶机的工艺参数 ,根据生产线实测结果 ,用相关方法分析了打叶复烤生产线流量、打前烟叶含水率、温度及打叶机组工艺参数对打叶去梗质量及出片率的影响。结果表明 ,随着打叶流量逐渐增大 ,碎片率呈近似“U”形变化趋势 ,叶中含梗率及梗中含叶率也随之升高 ;在一定范围内 ,随着打前烟叶含水率和温度的升高 ,>12 .7mm叶片率提高 ,<3.18mm碎片率和梗中含叶率降低 ;随着 >12 .7mm叶片率的提高 ,虽可减少打叶造碎及梗中含叶率 ,提高出片率 ,但会增大叶中含梗率。     

温湿度与粗纺纱线质量的关系

车间温湿度是影响纺纱工艺的重要因素之一,分析了纺织厂温湿度对粗纺纺纱质量的影响。对车间温湿度的波动情况进行分析,从温湿度对粗纺生产工艺和纱线条干均匀度的影响2方面进行了理论探讨。实践表明:温湿度过高或过低均不利于纺纱生产的进行,且影响纱线的条干水平,稳定的车间温湿度是提高纺纱质量的前提,控制车间温湿度的实质是控制半成品或成品的回潮率,以达到稳定生产、提高产质量和节能的目的。     

Cooking rate, pH and final endpoint temperature effects on color and cook loss of a lean ground beef model system

To assess the effects of pH, heating rate and endpoint temperature on instrumental and visual color of ground beef, pH was adjusted to 5.2–6.4, samples were heated at 0.7°C or 3°C/min to 55, 60, 65, 70, 75 or 80°C in a water bath. Cooking rate had no effect on cook loss, instrumental or visual color. Regression equations for linear, quadratic and/or cubic effects of pH and/or endpoint temperature were significant for most color indices. Amount of variance explained by the model and R² was increased by adding the calculated percentages of metmyoglobin and/or deoxymyoglobin to the regression models. The predicted sensory brownness score (0=very pink, 7.5=intermediate pink/brown, 15=intense brown) for samples with pH 5.75 cooked to 70°C was 9.75. Samples with a pH of 5.5 achieved this brownness score at 67°C. Samples with a pH of 5.2 achieved this brownness at 58°C.     

Relationship between meat quality and cooking losses

Summary. On the basis of visual assessment of exudative appearance, hams and shoulders were divided into two categories before curing: the 'normal' and the exudative ones. The 'normal' category included the DFD (dark, firm, dry) and the intermediate types having significantly lower average cooking loss. Since the two conditions are easily recognized, a preliminary selection is quite efficient. The efficiency of selection depends on the incidence of exudative meat to be processed. In the case of high incidence, selection may improve uniformity of pork products by decreasing cooking losses.     

Relationship between composition and stability of bovine milk lysozyme.

The amino acid analysis, peptide mapping, and heat stability of bovine milk lysozyme are presented. The bovine milk lysozyme molecule contains approximately 154 amino acids and is strikingly different in amino acid content from human milk lysozyme and egg white lysozyme. Tryptic hydrolysis yielded 26 peptides, all of which are unique from tryptic peptides of human milk lysozyme and egg white lysozyme. In addition, bovine milk lysozyme was more heat stable than human milk lysozyme at pH 4.0 but more labile at pH 7.0 and 9.0. Possible explanations for the differences in heat stability are discussed.     

小麦谷蛋白溶胀指数与面团特性及面条品质相关性分析

选用30种小麦,通过谷蛋白溶胀指数(SIG)与面团特性及面条品质的相关性研究,进而评价谷蛋白溶胀指数在预测蛋白质品质中的应用.结果表明:SIG与面团品质参数形成时间、稳定时间、弱化皮、拉伸曲线面积具有显著相关性,相关系数分别为0.537,0.547,-0.516,0.469;SIG20与面条品质参数最佳蒸煮时间、咀嚼性、弹性具有显著相关性,相关系数分别为0.455,0.477,-0.521,与硬度具有相关性,相关系数为0.334.谷蛋白溶胀指数比其他3种预测方法更简单,相关性更好,更适合中国小麦蛋白质品质预测,可以用于指导品质育种、谷物化学研究、面制食品加工.     

羊毛丝光工艺与高温湿热黄变的关系

文章对羊毛的丝光工艺和黄变机理进行了深入研究.采用3种工艺,通过工艺优化,为企业生产提供可靠的工艺数据;通过比较3种丝光工艺,发现不同的丝光工艺丝光毛白度不同,不同工艺的丝光毛遇高温水煮黄变的程度也不同,高温水煮过程中,加抗氧化剂可明显降低黄变;脱氧酶在丝光工艺中的应用,有利于提高丝光毛白度并降低残留氧化剂在后续工艺对纤维造成的损伤与黄变.     

Changes in water quality during heating in electromagnetic and gas heated pans and the relationship between water quality changes and temperature increase rate

Relatively large changes in the indicators of water quality, such as pH, hardness, and bicarbonate content, were observed during electromagnetic heating of pans of different tap waters and compared with pans heated by liquid natural gas (LNG) or liquid petroleum gas (LPG). For example, the pH and hardness of Hiroshima tap water were increased from 7.35 to 9.27 and from 19.0 to 35.7 mg L^?1, respectively, during 20 min of electromagnetic heating. When tap water from Tokyo was subjected to electromagnetic heating, the water hardness of 74.2 mg L^?1 was increased by 52% after 20 min of heating. Such water quality changes were observed consistently in several tap water samples across Japan. These changes showed a close correlation with rates of temperature increase. It was suggested that mineral components (Ca and Mg), which were attached on the stainless steel surface of the pans might be released into the tap water with high calorific heating.     

Relationship between individual herd-heritability estimates and sire misidentification rate

The objectives of this study were to estimate heritabilities within herds participating in Dairy Herd Improvement and determine the relationship of the individual herd heritability with sire misidentification rate. Individual herd heritabilities for milk, fat, and protein yield and somatic cell score (SCS) were calculated with daughter-dam regression and daughter-sire predicted transmitting ability (PTA) regression using 4,712,166 records from 16,336 herds available for August 2000 evaluations and 7,084,953 records from 20,920 herds available for August 2006 evaluations. Herd heritabilities were estimated using regression models that included fixed breed, age within parity, herd-year-season of calving, dam records nested within state, sire PTA within state, and an interaction between sire PTA and herd variance; random regression coefficients were dam records within herd and sire PTA within herd. Average daughter-dam herd heritability estimates ranged from 0.21 (SCS in 2000) to 0.73 (protein percentage in 2006), whereas daughter-sire herd heritability ranged from 0.10 (SCS in 2000) to 0.42 (protein percentage in 2006). Verification of sire identification with DNA marker analysis was provided by Accelerated Genetics and Alta Genetics Inc. Daughter-sire herd heritability was more strongly correlated with sire misidentification rate than daughter-dam herd heritability. The correlation between the first principal component for all measures of herd heritability and sire misidentification rate was −0.38 (176 herds) and −0.50 (230 herds) in 2000 and 2006, respectively. Herd heritability can be estimated with simple regression techniques for several thousand herds simultaneously. The herd heritability estimates were correlated negatively with sire misidentification rates and could be used to identify herds that provide inaccurate data for progeny testing.