鱼肽的抗疲劳功能研究

用鲢鱼副产物中蛋白质酶解得到的鱼肽饲喂小鼠4周,小鼠运动后血乳酸的恢复速率比对照组提高25%(P<0.05);血尿素氮含量明显降低,运动后恢复期血乳酸恢复速率加快,游泳时间明显延长,说明水解鲢鱼副产物鱼肽具有抗疲劳作用。     

畜产品质量安全存在的问题及对策分析

当下畜牧产品质量安全事件接连不断发生,让人们对畜产品质量的安全更为关注,分析畜产品质量的影响因素,对目前畜产品的质量安全问题进行探讨,针对质量安全问题提出相应控制对策。     

Rapid Determination of Carbon,Nitrogen, Silicon,Phosphorus, and Potassium in Sugar Mill By-products,Mill Mud,and Ash using Near Infrared Spectroscopy

This article describes a proof-of-concept exercise to examine the ability of near infrared spectroscopy (NIRS)–based methods to predict the major nutrient properties of sugar mill by-products, particularly mill mud, ash, and mixtures of mud and ash. Sixty mill mud, mixed mud/ash, and ash samples were subsampled three times and analyzed using traditional analytical techniques for carbon (C), nitrogen (N), silicon (Si), phosphorus (P), and potassium (K), and the NIR spectra were recorded. Two different partial least squares (PLS) regression models were constructed, one using all samples and the other without the ash samples included in the model development. Three mud, one mixed mud/ash, and two ash samples were retained for predictive purposes and were not included in the model development process. R² values in the range of 0.77 to 0.98 were obtained for all constituents across both sets of PLS models. The standard errors of prediction (SEP) were similar for both models for N (0.10 and 0.08), P (0.17 and 0.16), and K (0.05 and 0.05). However, the SEP obtained for Si (3.53 and 1.04) and C (1.92 and 1.00) varied between the two models. These preliminary results are very encouraging. Future research will extend to robust NIRS calibrations for these nutrients and develop applications for their use within laboratory or field situations to permit nutrient monitoring in various sugar mill by-products.     

清末武汉的农副产品进出口贸易

清末中国陷入半殖民地半封建社会的深渊,中国的市场被卷入世界资本主义市场内,沦为西方列强的经济附庸,成为西方资本主义经济的原料产地和产品倾销市场,被迫向他们大量出口原料及土产品,并大批进口洋货。被称为九省通衢的武汉因这种进出口贸易变得极度繁盛,一跃成为当时仅次于上海的全国第二大城市,素有东方芝加哥之美誉。     

Effects of Different Dietary Cotton by-products Levels on Production Performance,Nutrient Digestibility and Blood Biochemical Indexes of Sheep

The study was conducted to determine the effects of different dietary cotton by-products levels on production performance,nutrient digestibility and blood biochemical indexes of sheep.30 healthy sheep were chosen and randomly divided into 5 groups with 6 sheep per group. The feed of each group was that 50% formula concentrate feed was mixed with 50% wheat straw (control group),25% wheat straw and 25% cotton stalk (group Ⅰ),50% cotton stalk (group Ⅱ),45% cotton stalk and 5% cotton seed (group Ⅲ),and 40% cotton stalk and 10% cotton seed(group Ⅳ), respectively. The experiment lasted for 60 d. The result showed that:① The total weight gain and ADG of sheep showed a decreased with the increase of cotton stalk added proportion in the diets, and the total weight gain and ADG of group Ⅱ were significantly lower than group Ⅲ (P<0.05).② The concentration of NH₃-N was increased or decreased at different levels after adding different proportions of cotton by-products,and the TVFA and propionic acid concentration were not significantly affected (P>0.05).③ There was no significant difference of intake nitrogen, fecal nutrogen and uninary nitrogen among groups (P>0.05),but apparent digestibility of NDF and ADF showed a downward trend with the increase of cotton by-products added proportion in the diets,which were extremely significantly lower than control group (P<0.01).④ There were no significant differences among groups of the blood white cell count,red cell count,hemoglobin concentration,total protein,albumin,globulin,serum iron,sodium,chlorine and potassium content (P>0.05),but serum magnesium was significantly increased with increases of gossypol content in the diets (P<0.05). In conclusion,when the cotton by-products addition level in diets reaches 50% caused the free gossypol concentration in the feed more than 300 mg/kg, it would has certain negative effects on the production performance and health of sheep,and the cotton stalks add ratio in the diet should be controlled in the range of lower than 25%.     

Spatial and Temporal Variation of PM10 Mass Concentrations within the Greater Area of Athens,Greece

The formation of chlorination by-products (CBPs) was investigated through bench-scale chlorination experiments with river water. The compounds selected for analysis belonged to the groups of trihalomethanes, haloacetic acids, haloketones and haloacetonitriles. Trihalomethanes and haloacetic acids were the major species formed during chlorination, while haloketones and haloacetonitriles occurred at lower levels. The factors affecting the formation of these compounds were examined by two sets of experiments; the first with varying pH and reaction time, and the second with varying chlorine dose and temperature. Different effects of these factors were observed for different categories of CBPs, and in many cases, these effects were compound-specific, as confirmed by statistical analysis. Optimization of chlorination conditions in water treatment plants is a critical issue that should take into account the influence of chlorination parameters on the formation of individual CBPs.     

氨基酸氯化消毒副产物的生成机理研究

氯消毒是造纸废水再生利用过程中常用的消毒方法,它可以有效杀灭病原微生物,但同时也会生成各种具有毒性效应的消毒副产物。消毒过程中氯会与水中含氮有机物发生反应,生成各种形式的副产物,对人体健康产生危害。作者选取了四类氨基酸为研究对象,对它们与氯反应副产物的生成机理分别进行了讨论。     

Characterization of New Zealand Hoki and Southern Blue Whiting Surimi Compared to Alaska Pollock Surimi

Representative commercial lots of surimi produced from the New Zealand fish species hoki (Macruronus novaezelandiae) and Southern blue whiting (Micromesistius australis) were compared to that of Alaska pollock (Theragra chalcogramma) on the basis of functional properties and composition. Parameters studied included gelling response to preincubation and cooking for various times and to the addition of water and starch as well as frozen stability at -8°C. There were few species-related differences in response to the various treatments, although differences in absolute values of rheological parameters were noted. Surimi from the three species should be interchangeable with few or no modifications needed in the operating procedures of food manufacturers.     

超临界CO2萃取联合超声处理对凡纳滨对虾虾头油脂提取效果的影响

凡纳滨对虾在加工过程中会产生大量的虾头等副产物，其含有丰富的蛋白和脂类等物质。以虾头为原料，研究不同超临界CO2萃取压力（15~35 MPa）、温度（35~55 ℃）、时间（30~150 min）对虾头中油脂提取率的影响，采用超声波联合超临界技术提取油脂，气相质谱仪测定挥发性风味物质。结果表明，在超临界CO2萃取压力为30 MPa，35 ℃提取120 min时，虾头中油脂提取率为38.03%，联合超声处理（功率2.5 kW、频率35 kHz处理20 min），提取率可提高至52.97%±0.95%。经气相质谱检测，从虾头油脂中共检测出22种挥发性成分，包含烷烃类、醛类、酯类、酸类等。超声联合超临界提取方式可为对虾加工副产物的利用提供新技术。