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111.
This article examines the origins of the natural-wine movement in Germany—the first of its kind in Europe—by exploring the crucial technological and social developments which prompted the use of derided “artificial” winemaking techniques. The forgotten social reformer Ludwig Gall, once known to as the “savoir of the small vintner,” helped to relieve the unreliable dependency of winegrowers on nature by perfecting a deacidification technique which allowed for pleasant wines in any vintage. While Gall's technique became an important part of the road out of impoverishment for many winegrowers in the Mosel River Valley, it had the additional effect of challenging the static nature of the wine trade and the monopolies and economic efficiencies of large landowners. By outlining the initial uses of Gall's technique and the opposition to it, this article reveals the formative debates in the ongoing controversy over the definition of natural wine. In turn, the concepts of “artificial” and “natural” are shown to be grounded more in the social and political spheres of the nineteenth-century German wine trade and less in matters of consumer choice or concerns over the environment.  相似文献   
112.
We examined the effects of 2 grass silage-based diets differing in forage:concentrate (FC) ratio and those of a red clover silage-based diet on intake, milk production, ruminal fatty acid (FA) biohydrogenation, milk FA composition, and milk fat globule (MFG) size distribution. Ten multiparous Nordic Red cows received the following treatments: grass silage-based diets containing high (70:30, HG) or low (30:70, LG) FC ratio or a red clover silage-based diet with an FC ratio of 50:50 (RC) on a dry matter basis. Determinations of MFG were performed from fresh milk samples without addition of EDTA so the results of fat globules >1 µm in diameter are emphasized instead of the entire globule population. Lower FC ratio in grass silage-based diets increased milk production with no effect on daily fat yield, leading to 13% lower milk fat concentration. The effect of FC ratio on MFG size was moderate. It did not affect the volume-weighted diameter in grass silage-based diets, although LG lowered the volume-surface diameter of MFG in the size class >1 µm compared with HG. Compared with HG, feeding LG moderately decreased the biohydrogenation of 18:2n-6, leading to a higher level of polyunsaturated fatty acids in milk fat. Feeding RC lowered milk fat concentration and daily milk fat yield compared with grass silage-based diets. The volume-weighted diameter of MFG in the size class >1 µm was smaller in RC milk compared with grass silage-based diets. Feeding RC increased the flow of 18:3n-3 at the omasum by 2.4-fold and decreased the apparent ruminal 18:3n-3 biohydrogenation compared with grass silage-based diets despite similar intake of 18:3n-3. It also resulted in the lowest amount of saturated FA and the highest amounts of cis-9 18:1, 18:3n-3, and polyunsaturated FA in milk. In conclusion, LG decreased milk fat content and induced minor changes in MFG size distribution compared with HG, whereas RC lowered milk fat production, altered milk FA composition to nutritionally more beneficial direction, and led to smaller MFG compared with grass silage-based diets.  相似文献   
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114.
Boxes of beef were examined when product was packed and when boxes were loaded out of five packing plants, when boxes were loaded into and loaded out of seven refrigerated warehouses, and when boxes were received and opened at 21 retail stores. At each stage of handling at each facility, the boxes to be examined were selected at random. For each selected box, the temperature of product at the centre of the box was measured, and the date of packing and the plant of origin were noted. When cuts were packed, the minimum, median and maximum temperatures were about 2, 6 and 18 °C, respectively. Temperatures were successively lower when boxes were loaded out of packing plants, into warehouses and out of warehouses. When loaded out of warehouses, the minimum, median and maximum temperatures were about −2, 1 and 8 °C, respectively. The ranges of temperatures were similar, but the median temperatures were about 2 or 1.5 °C, respectively, when boxes were received at or were opened at retail stores. At packing plants and warehouses, the temperatures of manufacturing and ground beef were lower than those of cuts, but at the retail store the temperatures of all types of product were similar. When boxes were opened at retail stores, the minimum, median and maximum ages of cuts were about 2, 20 and 130 days, respectively; and the corresponding ages for manufacturing and ground beef were 2, 7 and 56 days, respectively. The data indicate that boxed beef is generally cooled to and maintained at temperatures within the range sought by the meat industry. However, cooling to chiller temperatures of product that is packed while warm can take several days; and some product is held for times that are excessive in view of the temperatures of boxed beef.  相似文献   
115.
碳水化合物的色谱分析对很多行业的研究来说都是非常重要的工作。例如.食品中单糖与二糖的定性定量,由于复杂糖类.糖醇、人造甜味剂与盐皆可形成复杂基质.使分析变得困难;制药行业通常使用简单或复杂的糖类或糖衍生物基质作为起始药物.通过对药物配方中的这些化合物进行分析,可以为生产提供所需要的信息;  相似文献   
116.
This study investigated the efficacy of high voltage atmospheric cold plasma (HVACP) treatment on degradation of aflatoxin in corn. Gas type (Air, MA65), relative humidity (5, 40, 80% RH), treatment time (1, 2, 5, 10, 20,and 30 min), mode of reaction, post-treatment storage, stirring of corn material were parameters investigated on degradation of aflatoxin by HVACP treatment. Generation of reactive gas species was characterized with optical emission spectroscopy and measured with dragger tubes. Generation of reactive gas species are influence by gas type and relative humidity. Higher concentration of ozone and NOx were generated during HVACP treatment in MA65 than in air and with lower relative humidity. Aflatoxin in corn could be rapidly degraded by HVACP treatment. Aflatoxin in corn was degraded by 62% and 82% by 1 and 10 min HVACP treatment in RH 40% air, respectively. The degradation kinetics of aflatoxin by HVACP treatment follows a logistic model. Higher degradation of aflatoxin was achieved in gas MA65, at higher relative humidities (40%, 80%). Direct or indirect HVACP treatment was equally effective in degrading aflatoxin in corn. Stirring the corn sample during HVACP treatment and post-treatment storage increased aflatoxin degradation in corn by HVACP treatment.  相似文献   
117.
118.
The application of quantitative real-time PCR (qPCR) technologies for the rapid identification of fecal bacteria in environmental waters is being considered for use as a national water quality metric in the United States. The transition from research tool to a standardized protocol requires information on the reproducibility and sources of variation associated with qPCR methodology across laboratories. This study examines interlaboratory variability in the measurement of enterococci and Bacteroidales concentrations from standardized, spiked, and environmental sources of DNA using the Entero1a and GenBac3 qPCR methods, respectively. Comparisons are based on data generated from eight different research facilities. Special attention was placed on the influence of the DNA isolation step and effect of simplex and multiplex amplification approaches on interlaboratory variability. Results suggest that a crude lysate is sufficient for DNA isolation unless environmental samples contain substances that can inhibit qPCR amplification. No appreciable difference was observed between simplex and multiplex amplification approaches. Overall, interlaboratory variability levels remained low (<10% coefficient of variation) regardless of qPCR protocol.  相似文献   
119.
Lipoprotein oxidation is a process thought to be involved in atherogenesis. Dietary antioxidants that prevent or inhibit oxidative damage to lipoproteins may help to prevent atherosclerosis. Both black and green teas can be major dietary sources of flavonoids and other phenolics with antioxidant activity. Results of previous studies suggest that green tea may have a greater antioxidant potential than black tea. The aim of this study was to assess and compare the effects of black and green tea on in vitro lipoprotein oxidation. The tea extracts were prepared using a method similar to that used to prepare infusions of tea for drinking. Antioxidant activities of seven black teas and four green teas were assessed using an in vitro assay that measures Cu2+ ‐induced oxidation of lipoproteins in human serum. All tea extracts inhibited in vitro lipoprotein oxidation in human serum to a similar extent. No significant difference in antioxidant activity was found between black and green tea. Caffeine prepared to a comparable concentration to that found in tea had no effect on lipoprotein oxidation. Further studies are required to determine the importance of these findings in relation to possible protective effects of black and green tea consumption against atherogenesis and cardiovascular disease. © 1999 Society of Chemical Industry  相似文献   
120.
Hunter L, a and b values are used to order fish mince colour according to species or processing parameters. Mince colour difference (ΔE) or statistical examination of L, a and b values are used to establish a 3-dimensional plot to illustrate colour differences between samples.  相似文献   
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