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1.
Sivadier G Ratel J Bouvier F Engel E 《Journal of agricultural and food chemistry》2008,56(21):9803-9812
Authentication of farm animal rearing conditions, especially the type of feeding, is a key issue in certification of meat quality and meat products. The purpose of this article was to analyze in parallel the volatile fraction of three adipose tissues excised from 16 lambs in order to authenticate two animal diets: pasture (n = 8) and concentrate (n = 8). On the basis of growth rate and anatomical location, three different lamb adipose tissues were analyzed: perirenal fat (PRF), caudal subcutaneous fat (CSCF), and heart fat (HF). An initial experiment was used to optimize the extraction of volatile compounds from the adipose tissues. Using a lipid liquid phase extraction, heating the ground tissue to 70 degrees C, was shown to be the best sample preparation mode before dynamic headspace-gas chromatography-mass spectrometry (DH-GC-MS) analysis to achieve a good representation of the starting material, while getting a good extraction and reproducibility. Next, the application of an instrumental drifts correction procedure to DH-GC-MS data enabled the identification of 130 volatile compounds that discriminate the two diets in one or several of the three tissues: 104 were found in PRF, 75 in CSCF, and 70 in HF. Forty-eight of these diet tracers, including 2,3-octanedione, toluene, terpenes, alkanes, alkenes, and ketones, had previously been identified as ruminant pasture-diet tracers and can be considered generic of this type of animal feeding. Moreover, 49 of the 130 compounds could identify diets in only one tissue, suggesting that complementary analysis of several tissues is superior for diet identification. Finally, multivariate discriminant analyses confirmed that the discrimination was improved when PRF, CSCF, and HF were considered simultaneously, even if HF contributed minimal information. 相似文献
2.
Anne-Laure Pennarun Carole Prost Michel Demaimay 《Journal of agricultural and food chemistry》2002,50(2):299-304
The study of the aroma of oysters is of great economic interest in France because it enables their organoleptic quality to be verified. The aim of this study is to optimize the extraction methods of the volatile compounds of oysters Crassostrea gigas in order to obtain an extract with an odor as close as possible to that of the original oysters'. Oyster aroma is rarely studied, and its sensory profile has not been investigated to date. Two extraction methods were studied: vacuum hydrodistillation carried out at 20 degrees C with noncrushed oyster using ultrapure water and dynamic headspace carried out using noncrushed oyster during a 30 min purge. They were compared with regard to their sensory characteristics by a panel of seven judges, all trained in seafood aroma recognition. This study has shown that vacuum hydrodistillation is the better method to obtain an extract closest in aroma to the oyster reference. 相似文献
3.
Jeleń HH Ziółkowska A Kaczmarek A 《Journal of agricultural and food chemistry》2010,58(24):12585-12591
Determination of the botanical origin of raw spirit used for alcoholic beverage production is of great importance for rectifying units, control laboratories, and proper product labeling. Raw spirit samples (138) produced from rye, corn, and potato were analyzed using a solid phase microextraction-mass spectrometry (SPME-MS) method, which involved volatiles preconcentration by SPME with subsequent volatile fraction characterization by MS without particular compounds separation by GC. Obtained data were treated using principal component analysis and linear discriminant analysis (LDA) to test the possibility of sample classification. SPME sampling conditions allowed rapid extraction in 2 min at 50 °C using a carboxen/divinylbenzene/polydimethylsiloxane fiber, followed by rapid MS analysis. Use of LDA made possible the classification of raw spirits based on the material they were produced from. The classification ability of the developed SPME-MS method was 100%, whereas its prediction ability was 96%. 相似文献
4.
泥沙来源“指纹”示踪技术研究综述 总被引：4，自引：0，他引：4
泥沙来源"指纹"示踪技术是综合研究流域土壤侵蚀和泥沙输移的新方法。泥沙来源"指纹"示踪技术基于流域侵蚀产沙过程划分潜在物源类型,根据物源特性筛选具有诊断能力的"指纹"性质,通过定量转换模型建立流域出口泥沙与内部潜在物源间的"指纹"联系,定量描述各潜在物源对流域出口产沙的相对贡献;结合悬移质或沉积泥沙通量监测,定量分析各潜在物源对流域产沙的绝对贡献量及流域侵蚀产沙时、空变化特征。通过综述泥沙来源"指纹"示踪技术的理论基础及实施框架,流域尺度潜在物源类型,泥沙"指纹"因子类别、分布特点及诊断能力,泥沙来源复合"指纹"示踪技术的研究进展,指出泥沙来源"指纹"示踪技术的局限性,并对泥沙来源"指纹"示踪技术进行展望。 相似文献
5.
Pennarun AL Prost C Haure J Demaimay M 《Journal of agricultural and food chemistry》2003,51(7):2006-2010
Oyster farming in France is a traditional activity. Each year, 149 000 tons of oysters are fattened before being sold. More and more oyster farmers supplement the diet of oysters by microalgae to optimize the fattening process and to improve both the growth and flesh quality of oysters. In the present study, oysters were supplemented by two microalgae: Skeletonema costatum and Tahitian isochrysis clone. The ash, protein, carbohydrate (including glycogen), and lipid contents were analyzed. The growth of oysters was improved when they were fattened with microalgae, leading to an increase in the condition index. The chemical composition of oysters was influenced by the chemical composition of the microalgae, especially the level of glycogen, which was significantly increased for oysters supplemented by microalgae. The fatty acid profile of oysters fattened by microalgae was positively correlated with the fatty acid profiles of S. costatum and T. isochrysis. These results show the effectiveness of supplementation by microalgae on the growth and on the biochemical composition (glycogen and fatty acids especially) of oysters. 相似文献
6.
7.
Roozbeh Mirza Mehdi Mohammadi Ali Dadolahi Sohrab Alireza Safahieh Ahmad Savari Pavaneh Hajeb 《Water, air, and soil pollution》2012,223(1):189-198
The concentration of polycyclic aromatic hydrocarbons (PAHs) was determined in seawater, sediment, and Rock oyster Saccostrea cucullata collected from four sampling sites in the inter-tidal areas of Bushehr province. The total concentrations of 14 PAHs varied
from 1.5 to 3.6 ng/L in seawater, 41.7 to 227.5 ng/g dry weight in surface sediment, and 126 to 226.1 ng/g dry weight in oyster
tissue. In comparing PAH concentrations among the three matrices in Bushehr province, data showed that the pattern of individual
PAHs in seawater, oyster, and sediment were different. The oysters tended to accumulate the lower molecular weight and the
more water-soluble PAHs. Sediment samples were distinguished from the sea water and oyster samples by the presence of high
molecular weight PAHs, especially six-ring PAHs. Three- and four-ring PAHs were the most abundant compounds among the 14 PAHs
investigated in surface seawater, sediment, and oyster samples. As expected, differences in octanol/water partition coefficient
among individual PAHs and the greater persistence of the higher molecular weight PAHs contributed to the accumulation patterns
in oyster and sediment. The results of the study suggested that the main sources of PAHs in the seawater and sediment in the
region were mixed pyrolitic and petrogenic inputs. 相似文献
8.
Introduction of non-indigenous species can alter marine communities and ecosystems. In shellfish farming, transfer of livestock, especially oysters, is a common practice and potentially constitutes a pathway for non-indigenous introductions. Many species of seaweeds are believed to have been accidentally introduced in association with these transfers, but there is little direct evidence.We experimentally simulated the transfer of oysters from the Thau Lagoon (France). These transfers involved increasing periods of aerial emersion and additional brine and hot water treatments. The brine and hot water treatments were evaluated as a means of reducing the probability of algal introductions with oyster transfers. Shells were cultured for 40 days in experimental tanks to identify the macroalgae likely to be introduced with any oyster transfer.A total of 57 macroalgal taxa, including 16 taxa not indigenous to the Thau Lagoon, were recorded across all treatments and experiments. The abundance of some species increased in several cases following aerial emersion. Elimination treatments (immersion in brine or hot water) significantly reduced algal diversity, with hot water treatments resulting in no species or only tubular Ulva spp. present.The results support the hypothesis that oyster transfers are effective as primary and secondary vectors of macroalgal introductions. Relatively simple changes to the transfer practice (particularly hot water treatments) are suggested as a means of reducing the risk of non-indigenous algal introductions. 相似文献
9.
收获时期对稻麦轮作水稻机收损失构成的影响 总被引：7，自引：3，他引：4
为了研究稻麦轮作区水稻机械化收获损失构成特征及其不同收获时期的变化规律,该文在统一管理的同一水田,从全田90%的谷壳变黄开始至100%谷壳变黄止共12 d进行机收试验,测试水稻千粒质量、收割机夹带稻谷质量、割台碰撞掉粒数量、收获的稻谷质量等的变化情况。研究结果表明,水稻机收损失呈一元二次方程变化规律,越靠近11月11日的最佳收获日作业,损失率越低。计算得到稻麦轮作区水稻机收适时性损失系数为0.0009,相对损失率稳定在1%左右,绝对损失率在1.00%~6.80%之间变化。干物质损失是机收总损失的最主要来源,11月9日至13日平均总损失率为1.38%,平均干物质损失率为0.42%,占水稻机收总损失的30.43%;11月4日至18日,平均总损失率为3.61%,平均干物质损失率为2.61%,占水稻机收总损失的72.30%,最佳收获期应为11月9日至11月13日,即最佳收获日左右5 d。该研究可为稻麦轮作区水稻收获机械优化配置提供参考。 相似文献
10.
Laursen KH Schjoerring JK Olesen JE Askegaard M Halekoh U Husted S 《Journal of agricultural and food chemistry》2011,59(9):4385-4396
The multielemental composition of organic and conventional winter wheat, spring barley, faba bean, and potato was analyzed with inductively coupled plasma-optical emission spectrometry (ICP-OES) and -mass spectrometry (ICP-MS). The crops were cultivated in two years at three geographically different field locations, each accommodating one conventional and two organic cropping systems. The conventional system produced the highest harvest yields for all crops except the nitrogen-fixing faba bean, whereas the dry matter content of each crop was similar across systems. No systematic differences between organic and conventional crops were found in the content of essential plant nutrients when statistically analyzed individually. However, chemometric analysis of multielemental fingerprints comprising up to 14 elements allowed discrimination. The discrimination power was further enhanced by analysis of up to 25 elements derived from semiquantitative ICP-MS. It is concluded that multielemental fingerprinting with semiquantitative ICP-MS and chemometrics has the potential to enable authentication of organic crops. 相似文献
11.
Mariana Altrichter 《Biological conservation》2005,126(3):351-362
Subsistence hunting practiced by poor rural and indigenous people in Latin America differentially affects the three species of peccaries (Artiodactyla: Tayassuidae). Sustainability of subsistence hunting of peccaries in the Argentine semi-arid Chaco, where the three species coexist, was unknown. My objectives were to determine the importance of peccaries for the local people, describe the current pattern of hunting and its impact on the three species of peccary and identify the factors that affect hunting sustainability. I found that many rural (70%) and village people (40%) consumed peccaries. White-lipped and chacoan peccaries were more susceptible to overharvesting than collared peccary. Current rates of hunting of white-lipped and chacoan peccaries are likely not sustainable because: (a) density of both species was between two to three times higher inside a protected area than outside; (b) populations have declined near larger villages and in older settlements; (c) herds sizes were small in comparison with other regions; (d) large number of juveniles less than one year old were harvested; (e) hunting did not discriminate based on sex or reproductive status and (f) The unified harvest model indicated unsustainable harvest because more than 40% of the reproductive production was taken and populations densities were less than 60% carrying capacities. In contrast, harvest of collared peccary seems sustainable at the current rates of hunting by rural peasants. Other threats such as forest exploitation, however, are accelerating, and are likely to reduce sustainability. 相似文献
12.
J T Tierney R Sullivan J T Peeler E P Larkin 《Journal of the Association of Official Analytical Chemists》1985,68(5):884-886
A collaborative study was performed to evaluate a method for determining numbers of poliovirus 1 in oysters. Commonly available laboratory equipment and materials were used. Raw oysters in the shell were shipped to each investigator along with 12 tubes of unknown concentrations of virus. Six 100 g duplicate oyster samples were analyzed by 5 collaborating laboratories. Each analyst used a prescribed procedure for diluting the inocula. Two samples contained approximately 100 plaque-forming units (pfu)/100 g, 2 samples contained approximately 50 pfu/100 g, and the other 2 contained approximately 25 pfu/100 g. Recoveries varied from 35 to 55% at inocula levels of 30-100 pfu/100 g. The limit of detectability was hypothesized to be 14 pfu in a 100 g sample when the recovery was 35%. The method has been adopted official first action. 相似文献
13.
Haibo Huang Wei Liu Vijay Singh Mary‐Grace C. Danao Steven R. Eckhoff 《Cereal Chemistry》2012,89(4):217-221
Efficiently utilizing the nongrain portion of the corn plant as ruminant food and the grain for ethanol will allow the optimization of both food and fuel production. Corn and corn stover could be more effectively used if they were harvested earlier before dry down. Corn harvested at different moisture contents (MCs) may exhibit different processing characteristics for the ethanol industry, because of differences in physical and chemical properties. Therefore, the objective of this study was to investigate the effect of corn harvest MC on dry‐grind fermentation characteristics and dried distillers grains with solubles (DDGS) composition. Pioneer hybrid 32D78 was harvested at seven different dates from August 21 to November 23, 2009, with harvest MCs ranging from 73 to 21% (wb). The corn samples with different harvest MCs were evaluated by a conventional dry‐grind process. Final ethanol concentration from the corn with harvest MC of 54% (kernel dent stage) was 17.9% (v/v), which was significantly higher (0.5–1.2 percentage points) than the mature corn with lower harvest MCs (P < 0.05). Ethanol conversion efficiencies for the corn with harvest MCs of 73 and 54% (wb) were 98.5 and 93.2%, respectively, whereas ethanol conversion efficiencies for the corn with lower harvest MCs were significantly lower (P < 0.05), ranging between 83.2 and 88.3%. For DDGS composition, with corn harvest MC decreasing from 73 to 21% (wb), the residual starch concentration increased from 7.7 to 15.2%, the crude protein concentration decreased from 29.4 to 24.9%, and the neutral detergent fiber concentration decreased from 26.6 to 20.6%. 相似文献
14.
It is well documented that marine oysters are net bioaccumulators of trace metals and they can be employed as biomonitors of time-integrated measurements of bioavailable metal fractions over their lifetime. In this study, the Malaysian mangrove flat tree oyster Isognomon alatus collected from the estuaries of Lukut River (five sites), Sepang Besar River (one site), and one metal-polluted site at Kg. Pasir Puteh were dissected into muscle, mantle plus gills, byssus, and remaining soft tissues. All the four different soft tissues were analyzed for Fe, Cu, and Ni. Significant spatial differences in the accumulated metal concentrations of the oysters were found between sampling sites, and these could be attributed to anthropogenic inputs including discharges of shrimp ponds (Lukut), animal husbandry (Sepang Besar), sewage, shipping, and industrial effluents (Kg. Pasir Puteh). For Fe, the tissue distribution followed: byssus > mantle plus gill >muscle > remaining soft tissues, while for Cu and Ni, both followed byssus > remaining soft tissues > mantle plus gill > muscle. This indicated that byssus could act as an excretion route for the metals. Based on a correlation analysis between oyster tissues and sediments, selected tissues of I. alatus were shown to be good biomonitors of Ni and Cu contamination, while high regulative capacity of Fe in the oyster tissues could hardly reflect the actual Fe levels in the surroundings. However, the clustering patterns based on metal levels in the four different soft tissues were not in agreement with those based on the geochemical fractions of sediment data. This phenomenon which was due to the metal contamination might not necessarily create high bioavailabilities of metals to the biomonitor I. alatus, which might involve differences in uptake, excretion, and sequestration of metals. Similarly to the Mussel Watch approach, this study points to the very potential use of the different soft tissues of I. alatus as biomonitors for regular biomonitoring in the mangrove area of Peninsular Malaysia. 相似文献
15.
Tarachiwin L Ute K Kobayashi A Fukusaki E 《Journal of agricultural and food chemistry》2007,55(23):9330-9336
Classification of tea quality is now mainly performed according to the sensory results by professional tea tasters. However, this evaluation method is inconsistent in differentiating their qualities. A combination of a (1)H NMR technique and a multivariate analysis was introduced to the quality evaluation of green tea by means of a metabolomic technique. A broad range of metabolites were detected by (1)H NMR spectrometry. The principal component analysis (PCA) was used to reduce the complexity of the (1)H NMR spectra data set and provided the quality discrimination result. It offered an extensive clue for classification and quality assessment without any prepurification method. A set of green teas from a Japanese tea contest were analyzed by (1)H NMR to classify the quality with respect to that judged by tea tasters and to conceive a quality prediction model. Metabolic profiling and fingerprinting of (1)H NMR spectra of green teas with different quality were studied. PCA showed a separation between the high- and the low-quality green teas. The taste marker compounds contributing to the discrimination of tea quality were identified. Reliable prediction models were obtained by the partial least-squares projection to latent structure (PLS) analysis together with a preprocessing filter of both orthogonal signal correction (OSC) and a combination between OSC and wavelet transform algorithms. 相似文献
16.
Aboriginal people in remote Australian communities have limited opportunity to participate in the market economy. The Aboriginal arts and craft industry offers an important option to generate cash income and the sustained supply of native plants used in production is vital. We assessed the current harvest of a rainforest tree species commonly used for sculpture, Bombax ceiba. Information from field surveys, a regional rainforest inventory and sales figures from the Maningrida region were used to estimate the population size and structure of B. ceiba, the harvest intensity of patches and the economic value of the harvest. We estimate the density of B. ceiba to be 105.10±12.32 stems ha−1 and a regional population of 76615±14063 stems. A cumulative harvest over 20 years of 6% suggests approximately 4596 stems harvested, and the harvest was worth about $200,000 over the last three years. The majority (80%) of harvested stems coppiced and were suitable for harvesting. Logistic regression suggests both distance to outstation and township influence harvesting intensity, with some localised over-harvest. Rainforests provide a valuable resource to Aboriginal artists in Maningrida and their maintenance provides important conservation benefits to the Australian community. 相似文献
17.
Nematicides are widely used to control plant-parasitic nematodes in intensive export banana (Musa spp.) cropping systems. Data show that the concentration of fosthiazate in banana fruits varies from zero to 0.035 g kg-1, under the maximal residue limit (MRL=0.05 mg kg-1). The fosthiazate concentration in fruit is described by a Gaussian envelope curve function of the interval between pesticide application and fruit harvest (preharvest interval). The heterogeneity of phenological stages in a banana population increases over time, and thus the preharvest interval of fruits harvested after a pesticide application varies over time. A phenological model was used to simulate the long-term harvest dynamics of banana at field scale. Simulations show that the mean fosthiazate concentration in fruits varies according to nematicide application program, climate (temperature), and planting date of the banana field. This method is used to assess the percentage of harvested bunches that exceed a residue threshold and to help farmers minimize fosthiazate residues in bananas. 相似文献
18.
Lin M Al-Holy M Al-Qadiri H Kang DH Cavinato AG Huang Y Rasco BA 《Journal of agricultural and food chemistry》2004,52(19):5769-5772
Fourier transform infrared spectroscopy (FT-IR, 4000-600 cm(-)(1)) was used to discriminate between intact and sonication-injured Listeria monocytogenes ATCC 19114 and to distinguish this strain from other selected Listeria strains (L. innocua ATCC 51742, L. innocua ATCC 33090, and L. monocytogenes ATCC 7644). FT-IR vibrational overtone and combination bands from mid-IR active components of intact and injured bacterial cells produced distinctive "fingerprints" at wavenumbers between 1500 and 800 cm(-)(1). Spectral data were analyzed by principal component analysis. Clear segregations of different intact and injured strains of Listeria were observed, suggesting that FT-IR can detect biochemical differences between intact and injured bacterial cells. This technique may provide a tool for the rapid assessment of cell viability and thereby the control of foodborne pathogens. 相似文献
19.
The effect of harvest and conditioned moisture contents (MC) on bulk density (BD) of rough, brown, and white rice was determined for several long- and medium-grain rice varieties harvested from different Arkansas locations. The results indicated that harvest MC (HMC) significantly affected the BD of freshly harvested and conditioned rough rice. Higher HMC levels resulted in lower BD levels for rough rice over the conditioned MC range from 11 to 29% (wb). There was a strong linear relationship between rough rice BD and conditioned MC for a given HMC. The harvest location had a more pronounced effect on rough rice BD of long-grain varieties than of medium-grain varieties. The BD of brown and white rice was less dependent on harvest location and conditioned MC than the BD of rough rice. Rice harvested at low MC level (≈13%) gave a higher BD for both brown and white rice than that harvested at higher MC levels. Medium-grain varieties showed a higher BD for brown and white rice than did long-grain varieties. 相似文献
20.
鸡只粪便的性状是反映鸡只健康状况的重要特征之一,不同性状的鸡便往往与特定的疾病相关联。针对鸡只粪便性状主要依靠人工监测,存在速度慢且易发生交叉感染等问题,该研究提出一种基于可见-近红外光谱技术的鸡只粪便分类判别模型。首先,通过扫描4类典型的鸡只粪便样本（正常粪便、红血丝粪便、绿色粪便和饲料粪便）在400～900 nm波段范围的光谱数据,对每一类别的鸡便样本按随机性原则以3∶1划分为校正集和测试集。其次,分别采用多元散射校正、SG卷积平滑和标准差标准化进行数据预处理,并建立偏最小二乘判别分析模型,根据模型评价指标确定最优预处理方法。然后,使用主成分分析、竞争性自适应重加权采样、改进的混合蛙跳3种方法对预处理后的样本进行数据降维,并最终建立分类判别模型。结果表明：基于模型评价指标确定最优数据预处理方法后,再采用改进后的混合蛙跳降维方法建立的判别模型区分正常粪便、红血丝粪便、绿色粪便表现最优,测试集判别准确率分别为92.27%、92.59%、100%;而对于饲料粪便,所选3种降维方法建立的判别模型,其测试集准确率均可达100%。因此,通过可见-近红外光谱检测手段,结合特征波长优选与偏最小二乘判别分析,可以有效判别不同类型的鸡只粪便,为实现鸡病智能化监测提供技术支持。 相似文献