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The physicochemical and functional properties of convection oven- and freeze-dried gluten meals of two corn varieties were evaluated. The physicochemical properties (water solubility index, water absorption index, Hunter color parameters, and bulk density) and functional properties (water absorption, oil absorption, least gelation concentration, protein solubility, and emulsification properties) of convection-oven and freeze-dried corn gluten meals were compared with each other and soy flour. Freeze-dried corn gluten meals was observed to have lower bulk density (0.244-0.263 kg/m3) and was lighter in color (high L and ΔE) compared to their counterpart convection oven-dried gluten meals. Freeze-dried gluten meals from both corn varieties showed significantly higher oil absorption, water absorption, pH, emulsification, and protein solubility compared to oven-dried corn gluten meals. The gluten meals from both corn varieties had lower water absorption and bulk density but higher oil absorption than soy flour, suggesting the hydrophobic nature of corn proteins. Corn gluten meals formed thin (pourable) emulsions compared to soy flour emulsions, which were thick salad dressing type. Freeze- and convection oven-dried corn gluten meals showed significantly lower protein solubility measured at different pH than soy flour.  相似文献   
3.
Total volatile basic nitrogen (TVB-N) as a measure of protein degradation and total microbial counts or stored raw mackerel (Trachurus murphy), which had been treated with chemical preservatives, were compared with the TVB-N and microbial counts of untreated fish. In unpreserved fish, decomposition of fish protein was rapid. Treatment of mackerel with acetic (1000-5000 μg kg?1), which was the most effective of the parameters studied, approximately halved the rate of increase in TVB-N compared with the untreated samples. Changes in the total microbial counts presented a similar trend.  相似文献   
4.
The distribution of fracture intensities occurring during compression of puffed corn meal extrudates was described using an exponential function, and parameters from that analysis were used as fracturability indices. Since “jagged” or oscillating stress-strain functions are typical for porous and brittle materials, fracture intensities were determined by measuring the abrupt, sequential reductions in stress produced during compression. Both distribution exponent and cumulative fracture stress correlated strongly with fracturability measured by other techniques, including fractal and Fourier analysis of stress-strain functions. Distribution parameters also indicated textural differences due to process parameters (structural modification through addition of different levels of sucrose) and storage conditions (equilibration at various relative humidities).  相似文献   
5.
Students (N = 167) from the 4th, 8th, and 11th grades sorted meals, listed on individual cards, according to whether they would or would not eat them. Students were told to either consider eating the meals at home or at school. Forty-two different meals were selected from a pool of unique meals created by students in a previous study. The meals differed in head component, the presence or absence of vegetables, and the number of different foodstuffs. On average, approximately half of the meals were deemed acceptable, but older students accepted more meals than younger ones, boys accepted more meals than girls, and meals to be consumed at home were accepted more than those to be consumed at school. In addition, students tended to accept meals comprised of a small number of foodstuffs that did not contain vegetables. The also chose more meat-based meals over those containing fish or soup. These results suggest that students have rather unique food preferences that do not correspond well with nutritional standards. In order to address this problem we recommended that students be given more good choices in the school cafeteria through the introduction of a two-meal system and salad bars.  相似文献   
6.
A model warehouse with carefully regulated environmental conditions was used to study the behavior of adult Indian meal moths during commodity infestation. Sequences of moth distributions in the warehouse, calculated by spatial analysis, clearly showed the coordinated movements of moth populations from eclosion to death. Many facets of adult behavior in a warehouse were coordinated with the photoperiod. Adult moths emerged at the end of a photophase and fairly rapidly moved to the walls and, to a lesser extent, to the undersides of the commodity pallets. Most females are mated in the first 24 h after emergence, largely during the scotophase. Air circulation within the warehouse probably compromised pheromone-directed guidance of males to females, although pheromones may still have a major role in regulating other aspects of male mating behavior. When mating subsided, many of the males flew upwind to the air circulating unit, but only during the photophases. The females moved to the return air side of the warehouse and then migrated towards the same end as the males, but only during the scotophases. They moved from pallet to pallet largely by walking on the warehouse floor and laid eggs in or on the cups of commodity. Direct oviposition on the commodity during the infestation period was lower than expected, probably because commodity odors were dissipated by air circulation and did not provide appropriate orientation. At 144 h after emergence, 90% of the moth population had died.  相似文献   
7.
生料系统用电量在水泥生产环节中占有较高比例,我公司4 800 t/d熟料生产线配置的生料磨型号为LM56.4莱歇立磨,设计能力450 t/h,主机功率4 000 kW。近几年通过采取技改技措手段、工艺参数调整、加强现场管理和小改小革等措施,不断优化生产工艺,达到降低生料系统电耗的效果,为生产系统节能降耗奠定基础,我公司生料系统年平均电耗由2017年的17.45 kWh/t下降至2020年的14.19 kWh/t,其中9月13.32 kWh/t,创造历史新低。  相似文献   
8.
采用STA同步热分析仪研究了铝矾土、水泥生料、石膏、水化水泥等在加热过程中的热效应及重量变化特征,以及水泥石膏结晶水受温度及加热方式对水泥性能影响,水泥水化为水泥石过程中氢氧化钙的形成及分解机理。进而为指导工业生产硫铝酸盐水泥生料配料,回转窑煅烧工艺参数控制等提供理论依据。  相似文献   
9.
我公司在生产过程中面临立磨停机以后窑尾废气SO2排放值较高的问题,给生产造成了很大的影响。为了解决这个问题,我公司引入热生料脱硫技术。通过不断优化调试方案,掌握了热生料脱硫技术的应用方法,并且解决了在应用过程中衍生的一系列问题。  相似文献   
10.
本文运用计算流体力学(CFD)技术,以大型流体工程计算软件CFX4.3为工具,模拟研究了喷煤燃烧器的扰焰罩长度对回转窑内煤粉燃烧过程规律的影响,结果表明,一定长度的扰焰罩有利于加强燃烧器出口附近的湍流混合和煤粉燃烧。  相似文献   
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