美国稻米分级标准与检测技术研究

美国通过出台严格、科学、合理的稻米分级标准和采用先进的检测技术来保证大米的质量达到出口要求,赢得市场的做法为我国稻米生产和贸易提供了有益的借鉴.面对竞争激烈的国际大米生产,我国惟有完善稻米标准,加大投入,提高检测水平,才能突破技术壁垒和绿色壁垒,实现由稻米生产大国向稻米生产强国的转变.     

美国稻米分级标准与检测技术研究

美国通过出台严格、科学、合理的稻米分级标准和采用先进的检测技术来保证大米的质量达到出口要求、赢得市场的做法为我国稻米生产和贸易提供了有益的借鉴。面对竞争激烈的国际大米生产,我国惟有完善稻米标准、加大投入、提高检测水平,才能突破技术壁垒和绿色壁垒,实现由稻米生产大国向稻米强国的转变。     

美国稻米分级标准与检测技术研究

美国通过实施严格、科学、合理的稻米分级标准和采用先进的检测技术来保证大米的质量达到出口要求,赢得市场的做法为我国稻米生产和贸易提供了有益的借鉴。面对竞争激烈的国际大米生产,我国惟有完善稻米标准,加大投入,提高检测水平,才能突破技术壁垒和绿色壁垒,实现由稻米生产大国向稻米强国的转变。     

美国稻米分级标准与检测技术研究

美国通过实施严格、科学、合理的稻米分级标准和采用先进的检测技术来保证大米的质量达到出口要求,从而赢得市场的做法为我国稻米生产和贸易提供了有益的借鉴.介绍了美国稻米质量的内涵;稻米外观品质、内在品质及检测技术;美国大米的分级标准;稻米卫生质量标准及检测技术;农药残留检测技术.指出面对激烈的竞争,我国惟有完善稻米标准,加大投入,提高检测水平,才能突破技术壁垒和绿色壁垒,实现由稻米生产大国向稻米强国的转变.     

韩国稻米政策与标准研究

围绕实现“大米自给”的目标,韩国稻米政策经历了片面追求增产到“开放式保护”的转变。韩国的稻米标准起步相对较晚,但发展很快,某种程度上借鉴日本稻米分级模式。在长期实践中也形成了一些独有的质量评价要素。预计,韩国稻米标准中包括农药残留标准、水分含量、食味值等指标将会有很大的变化。     

韩国稻米政策与标准研究

围绕实现“大米自给”的目标，韩国稻米政策经历了片面追求增产到“开放式保护”的转变?韩国的稻米标准起步相对较晚，但发展很快，某种程度上借鉴了日本稻米分级模式。在长期实践中也形成了一些独有的质量评价要素。预计，韩国稻米标准中包括农药残留标准、水分含量、食味值等指标将会有很大的变化。     

黑龙江省食用稻米品质的鉴定评价

对1985～1998年黑龙江省推广的49个水稻品种的稻米品质特性进行分析评价,指出垩白是影响我省稻米品质的主要因素．     

美国稻米标准与标准化生产研究

美国的稻米标准经过近百年的发展,已经成为科学、合理、严格的以碾磨程度和粒型为主要指标的标准体系。围绕稻米标准,美国依靠加大科技投入等措施,积极推进生产标准化生产,实现"优质、高产"的目标。美国的成功做法为我国稻米生产提供了借鉴。     

日本稻米标准的沿革与发展趋势

日本的稻米标准经过100多年的发展和完善，逐步形成了较为合理的以标准品为参照的标准体系，包括理化标准、食味标准和安全卫生标准。预计，今后日本的稻米标准将会在食味标准和农药残留标准等方面有新的变化。     

日本稻米标准的沿革与发展趋势

日本的稻米标准经过100多年的发展和完善,逐步形成了较为合理的以标准品为参照的标准体系,包括理化标准、食味标准和安全卫生标准。预计今后日本的稻米标准将会在食味标准和农药残留标准等方面有新的变化。     

中外大米质量标准对比分析及发展建议

为了促进国内外大米标准化交流和互鉴,从大米质量标准入手,对大米标准分类、适用范围、质量指标等进行了对比分析,找出标准间的相同和差异之处,并结合我国的实际,提出了今后大米标准化工作的相关建议。     

五谷杂粮锅巴工艺技术研究

以玉米、大豆、燕麦、芝麻、小米等五谷杂粮为主要原料,研制出营养丰富,口感较好,有特色的杂粮锅巴。与传统锅巴相比,五谷杂粮替代了传统锅巴中的大米等原料,用玉米淀粉替代了面筋,生产出的产品保留了五谷原有营养、风味和特性,具有很好的推广应用前景。     

Impact of production practices on physicochemical properties of rice grain quality

BACKGROUND: Rice growers are interested in new technologies that can reduce input costs while maintaining high field yields and grain quality. The bed‐and‐furrow (BF) water management system benefits farmers through decreased water usage, labor, and fuel as compared to standard flood management. Fertilizer inputs can be reduced by producing rice in rotation with soybeans, a nitrogen‐fixing crop, and with the use of slow‐release fertilizers that reduce nitrogen volatilization and run‐off. However, the influence of these cultural management practices on rice physicochemical properties is unknown. Our objective was to evaluate the influence of nitrogen fertilizer source, water management system, and crop rotation on rice grain quality. RESULTS: Grain protein concentration was lower in a continuous rice production system than in a rice–soybean rotation. Neither amylose content nor gelatinization temperature was altered by fertilizer source, crop rotation, or water management. BF water management decreased peak and breakdown viscosities relative to a flooded system. Peak and final paste viscosities were decreased by all fertilizer sources, whereas, crop rotation had no influence on the Rapid Visco Analyser profile. CONCLUSION: Sustainable production systems that decrease water use and utilize crop rotations and slow‐release fertilizers have no major impact on rice physicochemical properties. Published 2011 by John Wiley & Sons, Ltd.     

国内外稻谷出糙率、出米率和整精米率测定方法的比较研究及相关国际标准修订

介绍了国内出糙率检测方法、整精米率检测方法、稻谷和糙米潜在出米率测定方法等国家标准以及稻谷和糙米潜在出米率测定方法国际标准的主要技术内容,研究比较了国际标准与我国相关国家标准的技术差异和各自的优点,介绍了我国承担修订《稻米——稻谷和糙米潜在出米率的测定》国际标准的工作情况以及该国际标准修订前后的技术差异。     

Impact of cultivar variation in grain density of rice panicle on grain weight and quality

BACKGROUND: In the last two decades, newly released rice cultivars in southeastern China have been mainly characterised by more grains per cm panicle (GPCP), i.e. a compact panicle. These compact panicle cultivars show high yield potential but inferior quality. Accordingly, experiments were conducted to study the effect of GPCP on grain weight and quality. RESULTS: Two compact panicle and two loose panicle cultivars of japonica rice were used to investigate the effect of GPCP on the variation in grain weight and quality within a panicle. Significant differences in grain quality, including brown rice length, width and length/width ratio, brown rice and head‐milled rice percentages, chalky grain percentage and amylose and protein contents, were found among grains within a panicle. In general, the compact panicle cultivars showed lower grain weight and larger variation in brown rice length, width and length/width ratio, chalky grain percentage and amylose content among grains within a panicle than the loose panicle cultivars. CONCLUSION: GPCP is negatively associated with quality uniformity, and increasing the grain number on top secondary rachises may reduce the variation in grain weight and quality within a panicle. Copyright © 2008 Society of Chemical Industry     

Screening of rice cultivars for brewing high quality turbid rice wine

To screen proper rice cultivars for brewing high quality turbid rice wine, 5 high-yield rice cultivars, 9 high-eating-quality rice cultivars and 5 glutinous rice cultivars were collected. At the end of fermentation, significant differences (p < 0.05) were observed in the fermentation properties, sensory properties and suspension stability of the original fermented mash (OFM) among individual rice cultivars. The assayed fermentation properties of OFM included pH value, total acidity, amino acidity, reducing sugar, alcohol yield, fusel alcohols and ethyl acetate. Seven rice cultivars were screened out for producing high quality wine by the comparative analysis. This research provided the basic scientific data for producing potential high quality turbid rice wine.     

The effect of Thai glutinous rice cultivars, grain length and cultivating locations on the quality of rice cracker (arare)

Physicochemical and thermal properties of two Thai glutinous rice cultivars (RD6 and Short Grain) differing in grain length (whole grain and broken rice) and cultivating locations (the upper northeastern and the middle northeastern regions) and the quality characteristics of glutinous rice cracker produced from them were studied. RD6 cultivar was different in amylose content, gel consistency, volume expansion and hardness of rice cracker with those of Short Grain cultivar. Broken rice significantly gave greater amylose content, harder cool gel texture, less swelling, lower volume expansion and harder texture of rice cracker than whole grain rice. Furthermore, structure of starch molecule of broken rice differed from that of whole rice. The physicochemical, thermal properties and the qualities of rice crackers of RD6 cultivated from the upper northeastern and the middle northeastern regions showed no significant difference. To obtain good qualities of rice cracker, the rice should have lower amylose content, softer cool paste texture, greater breakdown value and less setback of amylogram. Amylose content and alkali gel consistency (120 mg flour) were significantly correlated with several other rice properties. The analysis of both properties is useful for the industry in controlling the quality of glutinous rice being used as raw material.     

Salt stress induces physiochemical alterations in rice grain composition and quality

Salinity has drastic effects on plant growth and productivity and is one of the major factors responsible for crop yield losses throughout the agricultural soils of the world. The mechanisms of salinity tolerance in plants are regulated by a set of inherent multigenes and prevalent environmental factors, which bring about a myriad of metabolic changes in each plant part. The stress-induced metabolic changes in the rice plant have been intensively studied, but extensively in plant parts such as stem, leaf, and root. However, little information exists in the literature about such stress-induced architectural and physiological changes in rice grain, a premier staple food of a large proportion of human population. Thus, the current review comprehensively describes the effects of salinity stress on rice grain composition including changes in carbohydrate, protein, fat, and mineral contents. Elucidation of salinity induced changes in rice grain composition would help to understand whether or not a nutritious and healthy staple food is available to human population from rice grown under saline environments.     

水分对优质稻储藏品质的影响

为改善优质稻储藏入库前含水量,本研究以不同水分梯度(11.5%、12.5%、13.5%、14.5%、15.5%、16.5%)的优质稻为研究对象,通过放入15、20℃进行模拟储藏。研究储藏过程中其整精米率、发芽率、发芽势、脂肪酸值、峰值黏度的变化情况。结果表明:准低温下储藏,含水量为12.5%～14.5%范围内整精米率较好,含水量为14.5%以下,其发芽率、发芽势较好,含水量为12.5%～15.5%都能保证脂肪酸值在较好水平,含水量对稻谷糊化特性影响较显著,含水量较低时峰值黏度较低,含水量升高峰值黏度逐渐升高;准低温以下温度储藏对优质稻整精米率、发芽率、发芽势影响不大,温度越高脂肪酸值、降落数值增加越快,RVA糊化特性受温度影响较大,温度高峰值黏度变化快。     

Strikingly high content of grain protein in solution‐cultured rice

A greenhouse experiment was conducted to investigate the nutritional quality of solution‐cultured rice. Five rice cultivars, different in grain amylose content and protein content, were grown under 10, 40 and 80 mg l^?1 nitrogen levels during the period of July 2003 to October 2003. In comparison to their original seeds, the solution‐cultured rice Oryza sativa L grain had strikingly higher protein content across all the cultivars and nitrogen levels, and remarkably lower amylose content in the waxy and low amylose cultivars, which might be due to the sufficiently stable nitrogen supply and well‐controlled temperature and humidity. The highest grain protein content was 163.6 g kg^?1 in this experiment, which is the highest reported rice grain protein content. The residual nitrogen concentration was greater than 12.39 g kg^?1 in the roots, 8.95 g kg^?1 in the stems, and 21.97 g kg^?1 in the flag leaves across all the cultivars and nitrogen treatments at harvesting. The rice grain had a narrow range of grain carbon content and hydrogen content. The average grain carbon and hydrogen contents for all the rice samples were 42.95 ± 0.15 (n = 60) and 6.81 ± 0.04 g kg^?1 (n = 60), respectively. The solution cultured rice grain was characterized with lower carbon–nitrogen mole ratio and lower hydrogen–nitrogen mole ratio, which could be mainly attributed to the increased protein content. The response of plant nitrogen, grain protein and amylose concentration to the supplemental nitrogen level varied with the cultivars. The results in this study suggested that solution culture technology could improve the production potential of rice. Copyright © 2005 Society of Chemical Industry