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111.
The objective of this study was to evaluate the predictive value of hedonic tests on apple juice carried out in a sensory laboratory, University common room and at home (post-consumption test) on ad libitum home consumption measured over 5 consecutive days. Thirty-five elderly volunteers (59–88 years old) and 33 young subjects (20–30 years old) assessed the degree of liking five apple juices varying in sweetness (0, 2, 4, 7 and 10% w/w sucrose added) on a nine-point hedonic scale. Both age groups judged similarly the juice with the lowest sugar concentrations, whereas the juice with 2% sugar added received lower scores from the elderly compared to the young participants. Those samples with higher sweetness (4, 7 and 10%) received higher scores from the elderly compared to the young people. The sample with no sugar added had higher mean score (all the subjects) in the home test (6.92±1.78) compared to both laboratory (5.51±2.15) and common room (5.92±2.08). No such differences were observed for the juices with the other sugar contents. In the elderly group, 1-day intake of apple juice remained on a similar level, regardless of sweetness liking, while among young adults the intake varied, and was highest for juices that were liked most (with 0 and 2% sucrose added). The results showed that hedonic ratings have a limited value as predictors of fruit juice consumption at home. The correlation between rated degree of liking and intake was low, especially for the elderly (r=0.39), indicating that factors other than pleasantness may affect intake. Among three test conditions, the lowest correlation of juice intake was obtained with laboratory test results (r=0.38), relatively higher—when hedonic tests were conducted in common room setting (r=0.49), or as the post-consumption test at home (r=0.73). Further research is required on sensory procedures relevant for the elderly, which together with some other nonsensory factors, would give a better prediction of consumption.  相似文献   
112.
A major fraction of nutrients emitted from households are originally present in only 1% of total wastewater volume. New sanitation concepts enable the recovery and reuse of these nutrients from feces and urine. Two possible sanitation concepts are presented, with varying degree of source separation leading to various recovery products. Separate vacuum collection and transport followed by anaerobic treatment of concentrated black water (BW) demonstrated on a scale of 32 houses preserve 7.6 g/N/p/d and 0.63 gP/p/d amounting to respectively 69 and 48% of the theoretically produced N and P in the household, and 95% of the retained P was shown to be recoverable via struvite precipitation. Reuse of the anaerobic sludge in agriculture can substantially increase the P recovery. Energy recovery in the form of biogas from anaerobic digestion of concentrated BW, fits well in new concepts of sustainable, zero energy buildings. Nutrient recovery from separately collected urine lowers the percentage of nutrient recovery in comparison with BW but can, on the other hand, often be implemented in existing sanitation concepts. Theoretically 11gN/p/d and 1.0 g P/p/d are produced with urine, of which 38-63 and 34-61% were recovered in practice on a scale of 8-160 inhabitants in Sweden. New sanitation concepts with resource recovery and reuse are being demonstrated worldwide and more and more experience is being gained.  相似文献   
113.
Recent research indicates a beneficial influence of a diet rich in β-carotene on human health. For that reason, experiments were undertaken to process winter squash with a high carotenoid content into ready-to-eat dried snacks. Sensory quality and dietary value of chips and crispy cubes made from different cultivars were investigated.The suitability of winter squash for drying purposes depended mainly on the dry matter content in the raw material. Although all the investigated cultivars can be used for producing chips, obtaining high quality porous cubes requires at least 15% of dry matter. ‘Justynka F1’ emerged as the most suitable cultivar for processing; both chips and cubes produced from its fruits were characterized by a high sensory quality and contained significant amounts of beta-carotene (225- 253 μg g-1). Also, the cultivar ‘Amazonka’ could be considered for the production of chips as it allowed us to obtain a product with a high beta-carotene content (200 μg g-1) and good sensory properties. The dried ready-to-eat crispy vegetable snacks made from the new cultivars of winter squash could be exploited as a novel attractive product with the attractive taste and colour to serve as a valuable source of carotenoids in human diet.  相似文献   
114.
Lead film electrodes (PbFEs) deposited in situ on glassy carbon or carbon paste supports have recently found application in adsorptive stripping voltammetric determination of inorganic ions and organic substances. In this work, the PbFE, prepared in ammonia buffer solutions, was investigated using scanning electron microscopy, atomic force microscopy and various voltammetric techniques. The microscopic images of the lead films deposited on the glassy carbon substrate showed a considerable variability in microstructure and compactness of the deposited layer depending on the selected experimental conditions, such as the concentration of Pb(II) species, the nucleation and deposition potential, and the time applied. The catalytic adsorptive systems of cobalt and nickel in a solution containing 0.1 ammonia buffer, 2.5 × 10−5 M nioxime and 0.25 M NaNO2 were employed to investigate the electrochemical characteristics and utility of the in situ prepared lead films.The optimal parameters, i.e. the lead concentration in the solution, the procedure of film removal, and the time and potential of lead nucleation and film deposition for the adsorptive determination of metal traces, were selected, resulting in the very good reproducibility (RSD = 4.2% for 35 scans) of recorded signals. The voltammetric utility of the lead film electrode was compared to that of glassy carbon, mercury film and bismuth film electrodes, and was subsequently evaluated as superior.  相似文献   
115.
Extinguishing forest fires is a critical issue for fire brigades; fire can spread throughout vast areas in a relatively short period of time. The studies presented in this paper describe the results of laboratory and field tests of new compositions of wetting agents for extinguishing wildland fires. The studies assessed the ability to penetrate surface fuels using 0.5 and 1% solution of wetting compositions. The penetration of the liquid through the layer of the loose rotting wood with solutions of obtained wetting agents was up to 68 times faster than with water. The absorption of water droplet was even 40 times slower in comparison to wetting agent solutions. Based on laboratory research, compositions that exhibit the best wetting properties were analysed in real conditions in field tests to assess their capacity to penetrate in surface fuels, their ability to make fire barriers and their efficiency in suppressing fires of soil cover and thickets. In tests performed in 4 m2 plots, the wetting compositions hold the flames from crossing a thin firebreak for up to three times longer periods than water. The results of the studies confirmed a significant increase in efficiency when new biodegradable wetting agents are employed to extinguish forest fires.  相似文献   
116.
BACKGROUND: The paper discusses biosorption of microelements by a freshwater macroalga Pithophora varia Wille to produce biological feed supplement for livestock. The biomass was enriched with microelements recommended by feeding standards in a single and a multi‐metal system. RESULTS: The equilibrium of biosorption was described by using a Langmuir model and the following values of the maximum biosorption capacity in the single‐metal system were obtained: Zn(II), 61.1 mg g?1; Co(II), 52.3 mg g?1; Cu(II), 55.7 mg g?1; and Mn(II), 38.3 mg g?1. The average value of maximum biosorption capacity expressed in molar units for all the cations was equal 1.7 ± 0.2 meq g?1, suggesting chemical rather than physical biosorption. It was also found that the mechanism of biosorption was due to cation exchange of alkali and alkaline earth metals with microelements. The biomass was also enriched with microelements in multi‐metal system. The total metal ion binding capacity in the multi‐metal system was two‐fold lower than in the single‐metal system and was 0.90 meq g?1 in the preparation for laying hens and 0.95 meq g?1 in the supplement for swine. CONCLUSION: Finally, the level of supplementation of livestock feed (with enriched single‐ and multi‐metal system macroalga), to cover 25% of total requirements for microelements, according to feeding standards, was provided. Copyright © 2008 Society of Chemical Industry  相似文献   
117.
118.
The work aimed at determination of electric properties of wheat grain in dependence on its variety, moisture, geometrical features of kernels and applied current frequency. Wheat grain of 4 Polish winter varieties: Korweta, Juma, Mikon and Kobra from harvest 2001 were used as the material for study. Grain was sized into 3 fractions: (1) > 2,8mm, (2) 2,5–2,8mm, and (3) 2,2–2,5mm. Basic geometrical features were determined for not sorted grain (control sample) and its three fractions by the use of digital image analysis. Electric properties of grain (at 11% and 15% moisture content) have been performed with the Hewlett Packard 4263B meter. Measurements of impedance, resistance, admittance, conductance, as well as equivalent parallel capacitance and equivalent series capacitance were made. Obtained results were subjected to statistical analysis with the use of Statistica? programme. Changes in electric properties of grain significantly depended on all of studied factors. Most of all significant correlations appeared between geometrical features and studied electric properties of grain of 15% moisture. Statistical analysis of the results proved significant linear correlations between electric properties of kernels and their length, perimeter and circularity coefficient RC2 at higher measurement frequencies.  相似文献   
119.
The study aimed to analyse the intake of Na with cereal products by the population of Poland. In addition, based on available literature, changes in the content of Na in bread sold in the Polish market from 2009 to 2018 were analysed with regard to Na intake reduction campaigns held in Poland since 2009 popularising information about the adverse effect of sodium on the human cardiovascular system. The results led to the conclusion that the analysed products contained 3.042 ± 3.4 g of Na per 1 kg of fresh product. The content of Na in the analysed products was bread > bread rolls > grains > pasta > rice. Cereal products provide 48.3 % of an adult’s intake of Na, where as much as 48.2 % is covered by bread, with only 0.04 % by grains, 0.04 % by pasta, and 0.01 % by rice. According to information available in reference literature from 2009–2017 the content of Na in baked goods has not been subject to significant modifications. In Poland, with regard to an excessive consumption of Na, efficient strategies must be developed to increase the awareness of consumers and to reduce the use of table salt in the most popular products, and in particular in baked goods. One of the ways to reduce the intake of Na would be consumers’ selection of an adequate range of foodstuffs naturally poor in this element or having its content reduced by means of a suitable technology. This can be a significant component of practices preventing the development of hypertension. However, the fact that information about the content of Na in cereal products is often missing from product labels makes consumer choice difficult.  相似文献   
120.
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