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泰国香米品质优良,具有较高的食味品质和营养价值,深受各国消费者喜爱,然而,市场上时常出现以次充好、掺伪等不良现象。建立泰国香米的快速鉴定方法,对于促进优质大米产业的可持续健康发展具有重要的意义。本研究基于泰国香米的近红外光谱和常规指标融合的多源信息,将155个泰国香米和194个非泰国香米样品一阶导数预处理后的近红外光谱与常规指标特征向量融合构成349行、14列向量矩阵,作为支持向量机分类器的输入向量矩阵,建立多源信息的融合模型,校正集和验证集模型的识别率均是100%,解决了近红外光谱等常用方法鉴别泰国香米时存在的准确率偏低的问题,实现了对泰国香米快速、准确地定性鉴定,在其掺伪识别方面具有重要的应用价值。 相似文献
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目的 研究基于气味活度值(odor activity value, OAV)下的泰国香米与普通大米中关键呈香化合物之间的差异。方法 根据挥发性物质总数、总峰面积、特征峰面积3个指标优化蒸米饭风味物质的萃取条件; 并通过固相微萃取-气相色谱-质谱法(solid phase microextraction-gas chromatography-mass spectrometry, SPME-GC-MS)对泰国香米与普通大米蒸煮后的挥发性风味化合物进行分析鉴定。结果 确定风味化合物的最佳萃取条件为: 取样量20 g、萃取温度60℃、萃取时间70 min、解析时间9 min。通过质谱鉴定和量化分析, 从泰国香米和普通大米中分别得到48种和29种风味化合物。结合OAV确定了泰国香米和普通大米中分别存在10种和8种关键呈香化合物, 如(E,E)-2,4-癸二烯醛、壬醛、1-辛烯-3-醇等物质, 其中2-乙酰基-1-吡咯啉是泰国香米区别于普通大米最关键的风味化合物。结论 本研究为分析米饭蒸煮后挥发性风味化合物提供了较为精准的检测条件, 同时为关键呈香物质的分析及泰国香米真伪的鉴别提供了基础支持。 相似文献
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香米市场鱼龙混杂
泰国香米是很多人喜爱的主食品种。它颗粒细长,用来煮米饭香气四溢,口感软糯。不过,最近经营杂粮店的李平却在市场上买到了假的泰国香米。他在批发市场进了70袋“孟乍隆”泰国香米,回到店里刚卖了几袋,就有人找上门要退货,称香米吃起来一点也不香。经工商执法人员调查后发现,这种称为“孟乍隆”泰国香米,其实是产在湖北的一种长粒米,是批发商用假冒的“孟乍隆”包装袋自己灌装的。 相似文献
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Yajun Wu Zhenming Zhang Ying Chen Bin Wang Guowu Yang Wanying Yang 《European Food Research and Technology》2009,229(3):515-521
A protocol for jasmine rice authentication was established in order to determine whether a Thai jasmine rice product meets
legal requirement. Both RAPD and SCAR methods were used on the basis of previous study of jasmine-rice specific genome characteristics.
Two RAPD markers, RI2-449 and RI5-1107, were selected and SCAR primer pairs were designed for RI5-1107. Twenty-four rice cultivars,
which represented typical jasmine rice and non-jasmine rice were analyzed to confirm the specificity and reproducibility of
DNA method. The purity of jasmine rice was calculated by analyzing every single kernel from test sample. Five in-house prepared
samples were quantified to prove the accuracy of DNA method, and 15 imported samples were analyzed by DNA method as well as
physical/chemical method to confirm the consistency between DNA method and traditional method. Based on the standard deviation
obtained by comparing DNA method and traditional method, a testing threshold for jasmine rice was decided. Investigation of
eight commercial samples from market showed that 75% products meet the requirement. 相似文献
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我国是稻米生产和消费的第一大国,稻米的市场稳定关系到我国粮食安全有效供给的大局。2012年1-5月份,国内稻谷和大米市场价格稳中有涨,国际大米价格先抑后扬。展望后市,在不发生重大自然灾害的条件下,预计国内稻谷和大米价格将维持稳中有涨的运行格局,短期内国际大米市场反弹空间有限。 相似文献
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High percentage inorganic arsenic content of mining impacted and nonimpacted Chinese rice 总被引:13,自引:0,他引:13
Zhu YG Sun GX Lei M Teng M Liu YX Chen NC Wang LH Carey AM Deacon C Raab A Meharg AA Williams PN 《Environmental science & technology》2008,42(13):5008-5013
Two approaches were undertaken to characterize the arsenic (As) content of Chinese rice. First, a national market basket survey (n = 240) was conducted in provincial capitals, sourcing grain from China's premier rice production areas. Second, to reflect rural diets, paddy rice (n = 195) directly from farmers fields were collected from three regions in Hunan, a key rice producing province located in southern China. Two of the sites were within mining and smeltery districts, and the third was devoid of large-scale metal processing industries. Arsenic levels were determined in all the samples while a subset (n = 33) were characterized for As species, using a new simple and rapid extraction method suitable for use with Hamilton PRP-X100 anion exchange columns and HPLC-ICP-MS. The vast majority (85%) of the market rice grains possessed total As levels < 150 ng g(-1). The rice collected from mine-impacted regions, however, were found to be highly enriched in As, reaching concentrations of up to 624 ng g(-1). Inorganic As (As(i)) was the predominant species detected in all of the speciated grain, with As(i) levels in some samples exceeding 300 ng g(-1). The As(i) concentration in polished and unpolished Chinese rice was successfully predicted from total As levels. The mean baseline concentrations for As(i) in Chinese market rice based on this survey were estimated to be 96 ng g(-1) while levels in mine-impacted areas were higher with ca. 50% of the rice in one region predicted to fail the national standard. 相似文献
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市场选择与优质食用稻米分级评价标准 总被引:1,自引:0,他引:1
从国内外大米市场的稻米价格比较角度,明确食用品质是优质食用稻米品质评价的关键质量指标。分析了我国稻米类标准评价结果与育种、生产和消费对稻米品质选择的符合程度,认为需要通过统一食用品质标准样品、实施评价员资格管理等措施,改进食用品质评价的可操作性,使优质稻米品质评价符合育种和生产现状,满足市场需求。企业可制订食用特性和等级标识引导分类消费,增加市场竞争力。 相似文献
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乌鲁木齐市售大米几项品质指标的初步分析 总被引:1,自引:0,他引:1
目的了解乌鲁木齐市售大米的品质状况,为市民购买大米提供参考依据。方法在市场调研基础上,选取乌鲁木齐市市售的不同产地、等级的15种代表性大米,通过原子吸收分光光度法(atomic absorption spectrometry,AAS)和近红外光谱法(near-infrared spectroscopy),检测大米的微量元素、蛋白质、脂肪、糖类等营养成分含量,对乌鲁木齐市场销售大米的品质进行初步研究;结果乌鲁木齐市场销售大米产地以东北和新疆为主;市场销售的东北一级大米价格比二级大米贵1.16元/kg,但其微量元素总含量差异不大,其他指标无显著差异;泰国香米微量元素含量、蛋白质、含糖量均高于新疆地产大米,但泰国香米的价格大约是新疆大米的4倍。因此,从性价比上考虑应该首选新疆地产大米。结论总体来看,新疆地产大米品质略低于东北产大米,但其具备价格优势。 相似文献
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TaqMan based real time PCR method for quantitative detection of basmati rice adulteration with non-basmati rice 总被引:1,自引:0,他引:1
S. Joseph Lopez 《European Food Research and Technology》2008,227(2):619-622
A TaqMan based real time PCR method is developed for the first time to check the adulteration in basmati rice. Betaine aldehyde
dehydrogenase 2 (BAD2) gene specific primers and probes were used to detect adulterant non-basmati rice content in basmati
samples. The results obtained with market samples and validation samples (basmati rice spiked with non-basmati rice in different
proportions) clearly revealed that this technique is useful to detect the adulteration very accurately with 1% detection limit. 相似文献
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目的验证实验室大豆、玉米和水稻及其制品转基因检测方法,并应用于实际样品检测。方法根据GB 19495.4-2018《转基因产品检测实时荧光定性聚合酶链式反应(PCR)检测方法》要求对无转基因标识的样品进行转基因成分检测。结果方法验证满意。40批次样品(大豆、玉米和水稻及其制品)中发现1批次的转基因成分检出,检出率为2.5%。结论市场中绝大部分未标示转基因成分的大豆、玉米和水稻及其制品确实未检出转基因成分,仅有极少数产品含有转基因成分,但未进行有效标识。 相似文献