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51.
Fining agents can also have an effect on the flavor components of the must, and other compounds which are important for the sensory characteristics and in the case of sparkling wine, the foam quality. The influence of fining agents and tirage solution, on volatile compounds, and foam characteristics of sparkling wines made from grapes of the Bobal variety was studied. The data obtained show how the fining agent affects the foam properties and the final volatile composition of sparkling wines. In this study, it was bentonite with gelatine that produced amounts of acetates and esters. The use of Colle 2P in the tirage solution means that more aromatic sparkling wines with better foam characteristics can be obtained.  相似文献   
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53.
A multicomponent phase-field method coupled to thermodynamic calculations according to the CALPHAD method was used to simulate microstructural evolution during directional solidification of the LEK94 commercial single-crystal Ni-based superalloy using a two-dimensional unit cell approximation. We demonstrate quantitative agreement of calculated microsegregation profiles and profiles determined from casting experiments as well as calculated fraction solid curves with those determined in differential thermal analysis (DTA) measurements. Finally, the role of solidification rate on dendrite morphology and precipitation of the secondary phases is investigated and a new measure of the dendrite morphology is presented to quantify the effect of back diffusion on the amount of secondary phases.  相似文献   
54.
The consumption of alcohol, cocaine and cannabis is associated with aggressive behaviour, being a victim of injuries from various causes, and suffering traffic accidents. On the other hand, there is a significant association between road rage and traffic accidents, yet this has not been studied in persons suffering a substance dependence disorder. This study analyses the prevalence of road rage in substance dependent patients undergoing treatment. 100 patients randomly selected at an outpatient treatment centre were included in the study. 63% of the patients had experienced road rage in the year prior to the interview, and 18% were serious perpetrators. There was a higher frequency among drivers and those who were starting treatment for cocaine and cocaine + heroin. The study shows that road rage is very frequent among patients with disorders due to substance dependence who are undergoing treatment, in particular the most severe form (“serious perpetrators”). Special attention should be addressed to the issue of driving and road rage during the treatment of these patients.  相似文献   
55.
We report a method to improve the thermal stability, up to 900 °C, of bare-metal (naked) gold nanoparticles supported on top of SiO(2) and SrTiO(3) substrates via ligand-assisted pinning. This approach leads to monodisperse naked gold nanoparticles without significant sintering after thermal annealing in air at 900 °C. The ligand-assisted pinning mechanism is described.  相似文献   
56.
The rate of anthocyanin extraction from skins of Monastrell grapes into wine during the maceration process has been studied by following anthocyanin accumulation in wine and its decrease in crushed skins. The most important changes occurred during the first 7 days of maceration; the following 7 days saw very little variation in the levels of the anthocyanins found in the wine or the crushed skins. The anthocyanin profile of the wines was quite different from that of the grape skins, whereas the crushed grape skins had a profile very similar to the profile of the grape skins at the time of harvest. Any differences in the proportions of the different anthocyanins found in Monastrell grapes and wines cannot therefore be attributed to different rates of extraction for each of the anthocyanins during winemaking. Other explanations, such as degradation or yeast cell wall adsorption, must be sought.  相似文献   
57.
The effects of raising the omega‐3 fatty acid (FA), conjugated linoleic acid (CLA), or omega‐3 FA plus CLA levels on beef by means of dietary supplementation and of adding grape seed extract (250 mg/kg meat product) in beef patties stored at 2 ± 1 °C in aerobic packaging under simulated retail display conditions for 6 d was evaluated by measuring the thiobarbituric acid reactive substances (TBARS), pH, and instrumental color measurement values and by means of sensory analysis. The pH, instrumental color measurements, and sensory attribute values for patties made from beef with augmented omega‐3 FA and/or CLA contents were similar to the values for the control patties made from beef from animals fed a conventional diet. Adding GSE lowered oxidation levels on day 6 (P < 0.001) and did not affect the instrumental color or sensory analysis results during the display period. This suggests that omega‐3 FA and CLA‐augmented beef could be used to make low‐fat beef patties having characteristics similar to those of conventional beef patties while being more in keeping with currently recommended nutritional guidelines.  相似文献   
58.
The effect of dietary vitamin E supplementation on lamb during vacuum‐packed storage was studied. Thirty‐six weaned male Manchego breed lambs were offered four dietary treatments (20, 270, 520 and 1020 mg vitamin E kg?1 feed). Lambs were fed the vitamin E‐supplemented diet from 13 until 26 kg live weight. Pieces of M. longissimus dorsi were stored under vacuum at 2 ± 1 °C in the dark and meat quality was assessed after 5, 14 and 28 days of storage. Dietary supplementation significantly increased the α‐tocopherol concentration in the muscle (P < 0.001). Initially, lipid oxidation, meat colour and bacterial load were similar in all groups. In meat of non‐supplemented lambs the thiobarbituric acid reactive substance value increased throughout storage, whereas in meat of supplemented lambs it did not increase. Meat pigments and discolouration proportion were significantly affected by storage time (P < 0.001). The bacterial load was low initially, but after 28 days of storage it was close to 7 log10 colony‐forming units (cfu) cm?2 and Enterobacteriaceae surpassed the limit of acceptability of 2.5 log10 cfu cm?2, making the lamb unsuitable for human consumption. Meat of supplemented lambs displayed less lipid oxidation than that of their non‐supplemented counterparts, while meat colour and bacterial load were not affected by supplementation. Copyright © 2007 Society of Chemical Industry  相似文献   
59.
BACKGROUND: Owing to the importance of the season of collection of milk for cheese quality, a study was made of the usefulness of near‐infrared spectroscopy (NIRS) for discriminating the seasonal origin (winter or summer) of milk and quantifying the fat content of cheeses, since fat is one of the components most affected by the season of collection of milk for the elaboration of cheeses. RESULTS: In the internal validation, 96% of samples from winter milk and 97% of samples from summer milk were correctly classified, while in the external validation the prediction rate of samples correctly classified was 92%. Moreover, quantitative models allowed the determination of fat in winter, summer and winter + summer cheeses. CONCLUSION: Rapid prediction of the fat content of cheeses and the seasonal origin (winter or summer) of milk was achieved using NIRS without previous destruction or treatment of samples. Copyright © 2011 Society of Chemical Industry  相似文献   
60.
Since the discovery of the 'formose reaction' by Butlerow, total synthesis of carbohydrates has undergone rapid development. The most important methods for the asymmetric synthesis of monosaccharides and analogues of biological importance are presented. Nowadays any natural and non-natural monosaccharide can be prepared pure in both enantiomeric forms starting from inexpensive starting materials. Metal-based asymmetric catalysis and organocatalysis have been successfully applied, alone or in combination with chemoenzymatic methods. Alternative methods rely upon substrate- or reagent-controlled diastereo- and enantioselective reactions. Suitably protected carbohydrates have been prepared by total synthesis, thus allowing their direct use in the preparation of oligosaccharides and analogues.  相似文献   
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