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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
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Fatty acid profile and sensory characteristics of table eggs from laying hens fed hempseed and hempseed oil 总被引:1,自引:0,他引:1
Goldberg EM Gakhar N Ryland D Aliani M Gibson RA House JD 《Journal of food science》2012,77(4):S153-S160
Hempseed (HS) is rich in omega-3 polyunsaturated fatty acids, with approximately 17% of total fatty acids as alpha-linolenic acid. As such, HS and its oil may be used in hen diet formulations to produce eggs enriched in essential fatty acids. Because omega-3 eggs have the potential for unpleasant aromas and flavors, the current study was designed to assess the fatty acid profile and sensory attributes of eggs procured from hens consuming diets containing hempseed oil (HO) or HS. A total of 48 individually caged White Bovan hens received 1 of 6 diets containing 4%, 8%, 12% HO, 10%, 20% HS or 0% hemp (w/w) for 12 wk. Total omega-3 polyunsaturated fatty acid content was highest in the 12% HO group (15.3 mg/g of yolk) compared to the control (2.4 mg/g of yolk). Trained panellists (n= 8) found no significant differences (P≥ 0.05) in aroma or flavor between cooked eggs from different dietary treatments, with the exception of sweet flavor. The 4% HO group yielded the least sweet eggs compared to the 20% HS group, which was highest. For yolk color, L*, a*, and b* values (Mean ± SEM) for control eggs were 61.2 ± 0.10, 1.1 ± 0.05, and 43.0 ± 0.22, respectively. Addition of hemp led to significant (P < 0.001) reductions in L*, and significant increases in a* and b*, with the largest changes observed in the 20% HS treatment (L*= 58.7 ± 0.10; a*= 5.8 ± 0.05; b*= 60.5 ± 0.22). The results show that hemp use in hen diets leads to increased omega-3 polyunsaturated fatty acid content and color intensity of egg yolks, but does not have adverse effects on the sensory profiles of the cooked eggs. PRACTICAL APPLICATION: This study provides evidence that HS and hempseed oil (HO) can safely be utilized as feed ingredients for laying hens to produce table eggs that are enriched in essential fatty acids. Additionally, the eggs procured from these hens had similar aroma and flavor compared to eggs from hens not fed any hemp. The greater the dietary hemp inclusion, the more pigmented the resulting yolks became in terms of darkness, redness, and yellowness. 相似文献
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The size of the manganese labile pools of three sandy soils from south east Scotland with a history of Mn deficiency was investigated by four methods: extraction with CaCl2; extraction with DTPA; E-value determination by exchange with 54Mn; and L-value determination using barley as the test crop. There was little agreement between the methods. The L-values varied with the period of plant growth and with soil bulk density but greatly exceeded the E-values, which in turn were about twice the quantities obtained by prolonged extraction with CaCl2 and an order of magnitude greater than the quantities extracted after 1 h with CaCl2-DTPA extraction gave values three to six times those obtained with CaCl2. Extractable Mn increased dramatically after prolonged air drying, indicating the need for standardisation of both pre-extraction conditions and extraction times when comparing the Mn availability of different soils. 相似文献
45.
ABSTRACT: The ability of 13 different strains of psychrotrophs to release free fatty acids in milk was evaluated by using GC analysis. The 13 strains could be categorized into 3 groups: Group 1 consisted of bacteria that grew well and released large quantities of free fatty acids, group 2 consisted of bacteria that grew well but released low amounts of free fatty acids, and group 3 consisted of bacteria that did not grow well nor released large quantities of fatty acids. In group 1, 3 strains were determined to be highly lipolytic, releasing short‐chain fatty acids in amounts greater than reported threshold values. Group 3 consisted of 2 strains, which did not grow well in heat‐treated milk, and the subsequent release of free fatty acids was minor during the 10‐d monitoring time. The other 8 strains tested showed no specific pattern of fatty acid release and quantities of short‐chain fatty acids were not large, despite the ability to grow to high numbers in the treated milk. This work indicates that the lipolytic activity of psychrotrophs common in raw milk is specific to the species and a general prediction of free fatty acid release may not be possible. 相似文献
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DM Clark PM Salkovskis LG Ost E Breitholtz KA Koehler BE Westling A Jeavons M Gelder 《Canadian Metallurgical Quarterly》1997,65(2):203-213
Cognitive accounts of panic predict that panic disorder patients will be particularly prone to misinterpret autonomic sensations. Several studies have produced results consistent with this prediction, but each is open to alternative interpretation. To clarify matters, 2 studies administered the Body Sensations Interpretation Questionnaire (BSIQ) to panic patients and controls. Panic patients were more likely to interpret ambiguous autonomic sensations as signs of immediately impending physical or mental disaster and were more likely than other anxiety disorder patients and nonpatients to believe these interpretations. In a 3rd study, a brief version of the BSIQ was shown to have satisfactory test-retest reliability, to change with treatment, and to discriminate treatments that varied in their effects on panic. 相似文献
50.
Limited natural resources, high energy consumption, economic considerations, and environmental concerns demand that we develop new technologies for the sustainable production of chemicals and fuels. New methods that combine the selective activation of C-H bonds of hydrocarbons with oxidation by a green oxidant such as molecular oxygen would represent huge advances toward this goal. The spectacular selectivity of transition metals in cleaving C-H bonds offers the potential for the direct use of hydrocarbons in the production of value-added organics such as alcohols. However, the use of oxygen, which is abundant, environmentally benign, and inexpensive (particularly from air), has proven challenging, and more expensive and less green oxidants are often employed in transition-metal-catalyzed reactions. Advances in the use of oxygen as an oxidant in transition-metal-catalyzed transformations of hydrocarbons will require a better understanding of how oxygen reacts with transition metal alkyl and hydride complexes. For alkane oxidations, researchers will need to comprehend and predict how metals that have shown particularly high activity and selectivity in C-H bond activation (e.g. Pt, Pd, Rh, Ir) will react with oxygen. In this Account, we present our studies of reactions of late metal alkyls and hydrides with molecular oxygen, emphasizing the mechanistic insights that have emerged from this work. Our studies have unraveled some of the general mechanistic features of how molecular oxygen inserts into late metal hydride and alkyl bonds along with a nascent understanding of the scope and limitations of these reactions. We present examples of the formation of metal hydroperoxide species M-OOH by insertion of dioxygen into Pt(IV)-H and Pd(II)-H bonds and show evidence that these reactions proceed by radical chain and hydrogen abstraction pathways, respectively. Comparisons with recent reports of insertion of oxygen into other Pd(II)-H complexes, and also into Ir(III)-H and Rh(III)-H complexes, point to potentially general mechanisms for this type of reaction. Additionally, we observed oxygen-promoted C-H and H-H reductive elimination reactions from five-coordinate Ir(III) alkyl hydride and dihydride complexes, respectively. Further, when Pd(II)Me(2) and Pt(II)Me(2) complexes were exposed to oxygen, insertion processes generated M-OOMe complexes. Mechanistic studies for these reactions are consistent with radical chain homolytic substitution pathways involving five-coordinate M(III) intermediates. Due to the remarkable ability of Pt(II) and Pd(II) to activate the C-H bonds of hydrocarbons (RH) and form M-R species, this reactivity is especially exciting for the development of partial alkane-oxidation processes that utilize molecular oxygen. Our understanding of how late transition metal alkyls and hydrides react with molecular oxygen is growing rapidly and will soon approach our knowledge of how other small molecules such as olefins and carbon monoxide react with these species. Just as advances in understanding olefin and CO insertion reactions have shaped important industrial processes, key insight into oxygen insertion should lead to significant gains in sustainable commercial selective oxidation catalysis. 相似文献