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Yanqiao Zhao Khanh Tran Margaret Brennan Charles Brennan 《International Journal of Food Science & Technology》2021,56(6):2687-2695
Polyphenols were extracted from five kinds of New Zealand grape pomace (Sauvignon Blanc, Pinot Gris, Gerwurztraminer, Merlot and Pinot Noir) at 30, 50 and 70 °C in an ultrasonic generator. The extraction kinetics for total phenol, anthocyanin and tannin were determined. The results of dynamics study showed that the extraction of total polyphenols, anthocyanin and tannin followed first-order reaction kinetics during the extraction at 30, 50 and 70 °C. The total phenolic content, anthocyanin conten, and tannin content of water–ethanol extracts from grape pomaces were compared, and the parameters in the extraction kinetics equations were determined. The extraction results showed that the Pinot Noir pomace extract had the highest total phenolic content of 59.95 mg GAE g−1 pomace and tannin content of 79.93 mg EE g−1 pomace. The anthocyanin content in Merlot pomace extract was the highest, which was 4.50 CE g−1 pomace. The results might be of great significance for the development of grape pomace or its polyphenol and/or anthocyanin components as an antioxidant source with natural and inexpensive benefits. 相似文献
3.
Adetiya Rachman Margaret A. Brennan James Morton Charles S. Brennan 《International Journal of Food Science & Technology》2020,55(8):3053-3060
Egg white protein and soy protein were incorporated into a banana and cassava flour blend (75:25) to produce gluten-free pasta. The objectives of study were to investigate the effects of the different protein sources on the physico-chemical properties of gluten-free pasta. The levels of protein inclusion were 0%, 5%, 10% and 15% of composite flour (w/w) for each type of protein. Pasta made from 100% durum wheat semolina was used as controls. The protein fortification affected the total starch, resistant starch and protein content of gluten-free pasta compared to semolina pasta. No significant effects of soy/egg white protein addition were found in either insoluble or soluble dietary fibre content. Cooking properties of pasta (optimum cooking time, swelling index, water adsorption index and cooking loss) and texture properties (firmness and extensibility) were affected by the level of protein addition and the type of protein. Results showed the utilisation of 25% cassava flour and protein inclusion have a promising application in gluten-free pasta production. 相似文献
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Neal C House WA Jarvie HP Neal M Hill L Wickham H 《The Science of the total environment》2005,344(1-3):107-128
Variations in phosphorus (P) concentrations in an agriculturally impacted river draining a Chalk aquifer and an associated canal in the west of the Thames Basin, southern England are examined and linked to agricultural and sewage sources and within river/canal process controls. The study area comprises the River Dun, the adjacent River Kennet and the Kennet and Avon (K&A) Canal. Large seasonal variations are observed for soluble reactive phosphorus (SRP) and dissolved silicon (Si) with low concentrations in the spring and summer times when biological activity is high. The K&A Canal shows the largest SRP and Si concentration declines. This reflects high biological activity coupled with higher temperatures and higher water residence times. The extent of SRP removal is examined in relation to organic (uptake/release with phytoplankton growth/decay) and, to a lesser extent, inorganic (SRP coprecipitation with calcite) mechanisms. Boron (B) is used as a tracer of sewage sources. Agricultural inputs of both dissolved and particulate P (PP) can be important particularly under conditions where the catchment is wet and near surface/overland flow is important: sewage treatment works effluent and septic tank discharges to groundwater also probably provide a major component of the SRP occurring within the water column. The canal, and to a lesser extent the river, acts as sink for P in sewage effluent sources due to the high biological activity especially during the spring and summer. The aquifer probably acts as a major sink for agricultural and septic tank inputs of P. 相似文献
6.
Chlorophyll-a in the rivers of eastern England 总被引:5,自引:0,他引:5
Chlorophyll-a concentration variations are described for two major river basins in England, the Humber and the Thames and related to catchment characteristics and nutrient concentrations across a range of rural, agricultural and urban/industrial settings. For all the rivers there are strong seasonal variations, with concentrations peaking in the spring and summer time when biological activity is at its highest. However, there are large variations in the magnitude of the seasonal effects across the rivers. For the spring-summer low-flow periods, average concentrations of chlorophyll-a correlate with soluble reactive phosphorus (SRP). Chlorophyll-a is also correlated with particulate nitrogen (PN), organic carbon (POC) and suspended sediments. However, the strongest relationships are with catchment area and flow, where two straight line relationships are observed. The results indicate the importance of residence times for determining planktonic growth within the rivers. This is also indicated by the lack of chlorophyll-a response to lowering of SRP concentrations in several of the rivers in the area due to phosphorus stripping of effluents at major sewage treatment works. A key control on chlorophyll-a concentration may be the input of canal and reservoir waters during the growing period: this too relates to issues of residence times. However, there may well be a complex series of factors influencing residence time across the catchments due to features such as inhomogeneous flow within the catchments, a fractal distribution of stream channels that leads to a distribution of residence times and differences in planktonic inoculation sources. Industrial pollution on the Aire and Calder seems to have affected the relationship of chlorophyll-a with PN and POC. The results are discussed in relation to the Water Framework Directive. 相似文献
7.
In the Middle East today, there are strong tensions between global and local aspirations in landscape architectural projects. Modernism, introduced to major cities in the Middle East, led to design approaches that are detached from local context, some adopting a tabula rasa attitude to site or inspired by Western models with little adaptation. Ambitious designers who seek to celebrate local values through context-based designs face dilemmas between client-driven global aspirations and local contextual particularities. This perspective essay critically reviews landscape design approaches in the region against discourses of Modernism, regionalism and critical regionalism. Projects in Abu Dhabi, Dubai, Riyadh and Muscat were examined to provide a spectrum of current trends in landscape practices. Insights gained show that valuing intangible cultural meanings attached to landscapes, acknowledging particular ecological processes and working within the profound connections between culture and ecology, are critical to inform future design strategies. 相似文献
8.
The water quality of the River Thame, a tributary of the River Thames in the Thames basin, is described in relation to point and diffuse contaminant inputs and runoff from permeable and impermeable bedrock geology with their own characteristic water quality. The data is examined to see if the market town of Aylesbury in the upper part of the catchment influences water quality. Previous studies highlighted the influence of Aylesbury sewage treatment works (STW) on soluble reactive phosphorus (SRP) concentrations in the river before and after phosphorus (P) stripping at the STW. Variations in water quality along the river are described and the study indicates that, apart from SRP, water quality determinants seem to be relatively unaffected by Aylesbury. The Thame water quality is compared with other catchment typologies and it is very similar to that of the main stem of the Thames even though the Thames is mainly Chalk groundwater fed. Differences in water quality largely link to the amount of STW effluent within the rivers and to the endmember compositions of the groundwater and near surface water sources. 相似文献
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10.
The mass of dioxins, PAH (polycyclic aromatic hydrocarbons) and VOC (volatile organic compounds) emitted from fires to the
atmosphere in Sweden per year has been estimated. The estimate is based on the number of fires in buildings, vehicles, waste
and forest fires in Sweden in 1999. It is estimated that the total emission of dioxins from fires is in the range 0.5–1.4 g
TEQ. The total emissions of PAH and VOC are in the ranges 2–12 ton and 13–200 ton, respectively.
The estimated emission of dioxins from fires approximately corresponds to the total emission from traffic or half the emissions
from municipal waste combustion (Swedish data from 1993).
The fire statistics show that the mass of material combusted in building fires during a year is approximately 7500 ton, while
that from forest fires is 2600 ton. Additionally, 2000–3000 tons are combusted in vehicle fires, fires in containers, etc.
In addition to the more common types of fires during a year, individual large incidents may contribute significantly to the
total emission. Such incidents include fires in municipal landfills or specific waste storage facilities (such as those for
used tyres). An assessment of the consequences of such incidents has been made. This assessment implies that a large contribution
to the emission of dioxins could be expected from fires in landfills and from fires in waste plastics (PVC) and tyres. Fires
in deposits of wood chips and tyres are also significant potential sources of PAH and VOC. 相似文献