[Objective] The aim was to research and identify starch grain microfossil found in archaeological sites in China, and to find appropriate procedures for the starch grain analysis experiment.[Method] Wheat starch grain...[Objective] The aim was to research and identify starch grain microfossil found in archaeological sites in China, and to find appropriate procedures for the starch grain analysis experiment.[Method] Wheat starch grain size distribution was analyzed, and some simulated experiments were carried out, like mortar grinding, ultrasonic treatment, hydrochloric acid and hydrogen peroxide immersion, drying treatment, and so on. [Result] The mean size of wheat starch grains had increased in the growth process. Mortar grinding would make wheat starch grains larger than untreated sample. Long time of ultrasonic treatment can also make the starch grain size larger. 10% HCl and 6% H2O2 would have little effects on morphological feature of wheat starch grains. Low temperature heating did not cause starch grains to be gelatinized. [Conclusion] These experiment results can improve the accuracy of starch grain microfossil identification in the archaeological site. Starch grain analysis may be a utility and effective analytical tool in studying the origin of agriculture and the dispersal of crops in China.展开更多
The starches were isolated by alkaline extraction from white and red sorghum, predominant cultivars in the Sahara of Algeria. Morphological, thermal properties and amylose content of isolated starches were examined. T...The starches were isolated by alkaline extraction from white and red sorghum, predominant cultivars in the Sahara of Algeria. Morphological, thermal properties and amylose content of isolated starches were examined. The starches of two sorghum landraces of white and pigmented kernels growing in hyper arid environmental conditions showed significant differences in granule size, amylose content and thermal behavior which ultimately affect the physicochemical and functional properties. When observed using environmental scanning electron microscopy （ESEM）. The starch granules showed polyhedral shape. Some of them showed pinholes. The granular size ranged between 6.325-39.905 μm and 7.096-44.774 μm, respectively for white and red sorghum starches. The granule size distribution was unimodal. The amylose content in white sorghum starch （27.1%） was higher than that in red sorghum （24.8%）. Differential scanning calorimetry （DSC） analysis revealed that sorghum starches present higher temperatures at the peak （70.60℃ and 72.28℃ for white and red sorghum starches, respectively） and lower gelatinization enthalpies （9.087 J/g and 8.270 J/g for white and red sorghum starches, respectively） than other cereal starches. The determination of these properties is relevant to the comprehension of starch and starch-based foods digestibility in order to direct them towards the specific applications in food and nonfood sectors.展开更多
基金Supported by National Natural Science Foundation of China(41072140)Chinese Academy of Sciences Strategic Priority Research Program(XDA05130402,XDA05130603)~~
文摘[Objective] The aim was to research and identify starch grain microfossil found in archaeological sites in China, and to find appropriate procedures for the starch grain analysis experiment.[Method] Wheat starch grain size distribution was analyzed, and some simulated experiments were carried out, like mortar grinding, ultrasonic treatment, hydrochloric acid and hydrogen peroxide immersion, drying treatment, and so on. [Result] The mean size of wheat starch grains had increased in the growth process. Mortar grinding would make wheat starch grains larger than untreated sample. Long time of ultrasonic treatment can also make the starch grain size larger. 10% HCl and 6% H2O2 would have little effects on morphological feature of wheat starch grains. Low temperature heating did not cause starch grains to be gelatinized. [Conclusion] These experiment results can improve the accuracy of starch grain microfossil identification in the archaeological site. Starch grain analysis may be a utility and effective analytical tool in studying the origin of agriculture and the dispersal of crops in China.
文摘The starches were isolated by alkaline extraction from white and red sorghum, predominant cultivars in the Sahara of Algeria. Morphological, thermal properties and amylose content of isolated starches were examined. The starches of two sorghum landraces of white and pigmented kernels growing in hyper arid environmental conditions showed significant differences in granule size, amylose content and thermal behavior which ultimately affect the physicochemical and functional properties. When observed using environmental scanning electron microscopy （ESEM）. The starch granules showed polyhedral shape. Some of them showed pinholes. The granular size ranged between 6.325-39.905 μm and 7.096-44.774 μm, respectively for white and red sorghum starches. The granule size distribution was unimodal. The amylose content in white sorghum starch （27.1%） was higher than that in red sorghum （24.8%）. Differential scanning calorimetry （DSC） analysis revealed that sorghum starches present higher temperatures at the peak （70.60℃ and 72.28℃ for white and red sorghum starches, respectively） and lower gelatinization enthalpies （9.087 J/g and 8.270 J/g for white and red sorghum starches, respectively） than other cereal starches. The determination of these properties is relevant to the comprehension of starch and starch-based foods digestibility in order to direct them towards the specific applications in food and nonfood sectors.
