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101.
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Dias EC Pereira RG Borém FM Mendes E de Lima RR Fernandes JO Casal S 《Journal of agricultural and food chemistry》2012,60(16):4120-4125
Immature coffee fruit processing contributes to a high amount of defective beans, which determines a significant amount of low-quality coffee sold in the Brazilian internal market. Unripe bean processing was tested, taking the levels of bioactive amines as criteria for evaluating the extent of fermentation and establishing the differences between processing methods. The beans were processed by the dry method after being mechanically depulped immediately after harvest or after a 12 h resting period in a dry pile or immersed in water. Seven bioactive amines were quantified: putrescine, spermine, spermidine, serotonin, cadaverine, histamine, and tyramine, with global amounts ranging from 71.8 to 80.3 mg/kg. The levels of spermine and spermidine were lower in the unripe depulped coffee than in the natural coffee. The specific conditions of dry and wet processing also influenced cadaverine levels, and histamine was reduced in unripe depulped coffee. A resting period of 12 h does not induce significant alteration on the beans and can be improved if performed in water. These results confirm that peeling immature coffee can decrease fermentation processes while providing more uniform drying, thus reducing the number of defects and potentially increasing beverage quality. 相似文献
104.
Hall JA Tooley KA Gradin JL Jewell DE Wander RC 《American journal of veterinary research》2002,63(1):104-110
OBJECTIVE: To determine effects of dietary n-3 fatty acids from Menhaden fish oil on plasma alpha-tocopherol concentrations in Beagles. ANIMALS: 32 female Beagles. PROCEDURE: For 82 days, dogs were fed diets that contained 1 of 2 ratios of n-6:n-3 fatty acids (40:1 [low n-3] and 1.4:1 [high n-3]) and 1 of 3 concentrations of all-rac-alpha-tocopheryl acetate (low, 17 mg/kg of diet; medium, 101 mg/kg; and high, 447 mg/kg) in a 2 X 3 factorial study. RESULTS: Diets high in n-3 fatty acids significantly increased total content of n-3 fatty acids in plasma (17.0 g/100 g of fatty acids), compared with low n-3 diets (2.02 g/100 g of fatty acids). Mean +/- SEM plasma concentration of cholesterol was significantly lower in dogs consuming high n-3 diets (4.59 +/- 0.48 mmol/L), compared with dogs consuming low n-3 diets (5.71 +/- 0.48 mmol/L). A significant interaction existed between the ratio for n-6 and n-3 fatty acids and amount of alpha-tocopheryl acetate in the diet (plasma alpha-tocopherol concentration expressed on a molar basis), because the plasma concentration of alpha-toco-pherol was higher in dogs consuming low n-3 diets, compared with those consuming high n-3 diets, at the 2 higher amounts of dietary alpha-tocopheryl acetate. Plasma alpha-tocopherol concentration expressed relative to total lipid content did not reveal effects of dietary n-3 fatty acids on concentration of alpha-tocopherol. CONCLUSIONS AND CLINICAL RELEVANCE: Plasma alpha-tocopherol concentration is not dependent on dietary ratio of n-6 and n-3 fatty acids when alpha-tocopherol concentration is expressed relative to the total lipid content of plasma. 相似文献
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106.
Barnard EE 《Science (New York, N.Y.)》1898,8(194):341-353
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Seven populations collected at different altitudes in northern Italy, two Ladino breeding populations and two control cultivars
(AberHerald and Grasslands Huia) of white clover (Trifolium repens L.) were included in a series of experiments analysing: (i) levels of cold tolerance using artificial and field-based methods;
(ii) relationships between these measures of cold tolerance; (iii) components of spring yield, various physiological traits,
and their relationships with cold tolerance. Rates of seedling and growing point mortality in the populations over winter,
assessed in separate field experiments, were closely related (r = 0.85). Grasslands Huia showed the highest death rates, and material originating from high altitudes the lowest. The LT50 value, i.e., the temperature at which 50% of the growing points would die, estimated by an artificial freezing test, was
significantly correlated with field-based measures of seedling (r = 0.64) and growing point (r = 0.84) mortality. The existence of these correlations is of potential interest for the development of indirect selection
criteria for complex and expensive-to-evaluate traits such as winter survival in field plots. Besides being reliable, in this
study the artificial assessment was also sensitive, providing a greater degree of separation of the populations means than
field-based measures. Of the several physiological traits (water content,concentrations of water soluble and total non-structural
carbohydrate, and water soluble protein content of stolons) measured at a mid-winter sampling date under field conditions,
the only character showing significant variation between populations was soluble protein content. There was a slight trend
for material with a higher protein content to exhibit greater field-based values of cold tolerance. High altitude populations
tended to have low spring yields. The highest spring yield was found in one of the Ladino populations. The study identified
two populations which combined, to differing extents, cold tolerance and spring yield characteristics that would be of potential
use in breeding for specified agronomic/climatic zones.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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110.
This paper presents data on the alkaline element chemistry of unpaved road surface materials and the potential flux of these elements into the atmosphere. Additionally, we discuss the potential acid neutralizing capacity of unpaved road surface materials in precipitation. The relative contribution of unpaved roads to the total open source flux of alkaline materials is also examined. Preliminary calculations indicate that unpaved roads contribute more than 90% of all open source Ca and Mg in 37 and 33 of the 48 contiguous states, respectively. 相似文献