[Objective] To accurately determine the components and content of fermentable sugars in wort. [Method] The components and content of fermentable sugars in wort made from degermed corn extruded at low temperature as be...[Objective] To accurately determine the components and content of fermentable sugars in wort. [Method] The components and content of fermentable sugars in wort made from degermed corn extruded at low temperature as beer adjunct were determined by HPLC. [Result] The contents of sugar components were shown as below: fructose was 3.8 g/L, glucose was 7.4 g/L, sucrose was 4.2 g/L, maltose was 53.8 g/L and maltotriose was 10.6 g/L.The content of the five fermentable sugars had good linear relation within their peak area in the determination range, the correlation coefficient was 0.977 6-0.990 7, the recoveries of samples were >96%, the standard deviation was 1.27%-3.26%. [Conclusion] The method is simple and rapid with high sensitivity and good reproducibility, it provides reliable and accurate analytic method for determining the components of fermentable sugars in wort made from degermed corn extruded at low temperature as beer adjunct.展开更多
The sugar components and their dynamic variation in the developing grains of sweet corn(Zea mays L. seccharata Sturt)and normal corn (Zea mays L. indentata Sturt) were compared. There are WSP (water-soluble polysaccha...The sugar components and their dynamic variation in the developing grains of sweet corn(Zea mays L. seccharata Sturt)and normal corn (Zea mays L. indentata Sturt) were compared. There are WSP (water-soluble polysaccharides), sucrose, fructose, glucose, mannitol and sorbitol in both sweet corn and normal corn, but no maltose. Two components with different degrees of polymerization (D. P. N) were detected in the sweet corn; only one of them was detected in the normal corn 20 days after pollination. With the development of grains, the total soluble sugar content(TSS)in sweet corn increased, but in normal corn it decreased. The dynamic variation of WSP, sucrose, glucose, fructose, mannitol and sorbitol in sweet and normal corn grains are different. The contents of sugar components in the sweet corn grains are higher than that in the normal corn. Sweet corn accumulates less starch than normal corn.展开更多
Transgenic Bt corn hybrids have been available for more than 10 years and are known to control specific insects. More recently, so-called “stacked-gene” hybrids, have been released with multiple insect resistance ge...Transgenic Bt corn hybrids have been available for more than 10 years and are known to control specific insects. More recently, so-called “stacked-gene” hybrids, have been released with multiple insect resistance genes and genes for herbicide resistance, resulting in up to 6 traits per plant. Because insect damage can lead to increased levels of mycotoxins, such as aflatoxins and fumonisin, we designed a study to compare ten commercially available corn hybrids, two non-transgenic, four with both herbicide and insect tolerance (stacked-gene) and four with glyphosate tolerance only to determine if any hybrid class had the advantage of reduced mycotoxin contamination. The experiment was carried out in the Mississippi State University Delta Research Extension fields in Stoneville, MS for two years in fine sandy loam and clay soil. Rows were either inoculated at the V10 stage of growth with toxigenic Aspergillus flavus K54 (NRRL 58987, isolated from corn kernels in Mississippi), grown on wheat, and applied at a rate of 22.42 kg/ha or allowed to become naturally infected with disease-producing fungi, including various Fusarium and other Aspergillus spp. Mycotoxin production differed according to the soil type with lower levels detected in the hybrids planted in clay soil vs. sandy soil. However, no significant differences in mycotoxin production were found amongst the hybrid classes. More research is needed to identify conditions under which transgenic hybrids might produce higher yields and lower mycotoxin levels. Presently, selection of transgenic hybrids will not replace integrated strategies of biocontrol, host plant resistance, or good crop management practices for achieving adequate mycotoxin control in corn.展开更多
基金Supported by Shandong Natural Foundation(Y2008B10)
文摘[Objective] To accurately determine the components and content of fermentable sugars in wort. [Method] The components and content of fermentable sugars in wort made from degermed corn extruded at low temperature as beer adjunct were determined by HPLC. [Result] The contents of sugar components were shown as below: fructose was 3.8 g/L, glucose was 7.4 g/L, sucrose was 4.2 g/L, maltose was 53.8 g/L and maltotriose was 10.6 g/L.The content of the five fermentable sugars had good linear relation within their peak area in the determination range, the correlation coefficient was 0.977 6-0.990 7, the recoveries of samples were >96%, the standard deviation was 1.27%-3.26%. [Conclusion] The method is simple and rapid with high sensitivity and good reproducibility, it provides reliable and accurate analytic method for determining the components of fermentable sugars in wort made from degermed corn extruded at low temperature as beer adjunct.
文摘The sugar components and their dynamic variation in the developing grains of sweet corn(Zea mays L. seccharata Sturt)and normal corn (Zea mays L. indentata Sturt) were compared. There are WSP (water-soluble polysaccharides), sucrose, fructose, glucose, mannitol and sorbitol in both sweet corn and normal corn, but no maltose. Two components with different degrees of polymerization (D. P. N) were detected in the sweet corn; only one of them was detected in the normal corn 20 days after pollination. With the development of grains, the total soluble sugar content(TSS)in sweet corn increased, but in normal corn it decreased. The dynamic variation of WSP, sucrose, glucose, fructose, mannitol and sorbitol in sweet and normal corn grains are different. The contents of sugar components in the sweet corn grains are higher than that in the normal corn. Sweet corn accumulates less starch than normal corn.
文摘Transgenic Bt corn hybrids have been available for more than 10 years and are known to control specific insects. More recently, so-called “stacked-gene” hybrids, have been released with multiple insect resistance genes and genes for herbicide resistance, resulting in up to 6 traits per plant. Because insect damage can lead to increased levels of mycotoxins, such as aflatoxins and fumonisin, we designed a study to compare ten commercially available corn hybrids, two non-transgenic, four with both herbicide and insect tolerance (stacked-gene) and four with glyphosate tolerance only to determine if any hybrid class had the advantage of reduced mycotoxin contamination. The experiment was carried out in the Mississippi State University Delta Research Extension fields in Stoneville, MS for two years in fine sandy loam and clay soil. Rows were either inoculated at the V10 stage of growth with toxigenic Aspergillus flavus K54 (NRRL 58987, isolated from corn kernels in Mississippi), grown on wheat, and applied at a rate of 22.42 kg/ha or allowed to become naturally infected with disease-producing fungi, including various Fusarium and other Aspergillus spp. Mycotoxin production differed according to the soil type with lower levels detected in the hybrids planted in clay soil vs. sandy soil. However, no significant differences in mycotoxin production were found amongst the hybrid classes. More research is needed to identify conditions under which transgenic hybrids might produce higher yields and lower mycotoxin levels. Presently, selection of transgenic hybrids will not replace integrated strategies of biocontrol, host plant resistance, or good crop management practices for achieving adequate mycotoxin control in corn.
