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141.
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Ragaee SM Campbell GL Scoles GJ McLeod JG Tyler RT 《Journal of agricultural and food chemistry》2001,49(5):2446-2453
Five rye lines exhibiting a wide range of extract viscosities were evaluated for the rheological and baking properties of their flours, individually and in blends with hard red spring wheat flour. Commercial cultivars of rye and triticale were included in the study as controls. Extract viscosities of rye flours were higher than those of corresponding wholemeals, indicating shifting of water-extractable arabinoxylan into flour during roller milling. Falling numbers of the rye flours correlated positively with their extract viscosities in the presence (r = 0.73, p < 0.05) or absence (r = 0.65, p < 0.05) of an enzyme inhibitor. Farinograms revealed the weakness of rye and triticale flours compared to wheat flour. Extract viscosities of rye flours were negatively correlated (r = -0.65, p < 0.05) with mixing tolerance index and positively correlated (r = 0.64, p < 0.05) with dough stability, suggesting a positive impact of extract viscosity on dough strength. Extract viscosity was negatively correlated (r = -0.74, p < 0.05) with loaf volume and specific volume (r = -0.73, p < 0.05) and positively correlated (r = 0.73, p < 0.05) with loaf weight of rye/wheat bread. Overall, the results indicated that 30% of flour from high or low extract viscosity rye could be incorporated into rye/wheat breads without seriously compromising bread quality. Inclusion of rye, particularly high extract viscosity rye, in chick diets seriously impeded growth performance and feed efficiency. Part of the arabinoxylan survived bread-making and exerted an effect on chicks, although substantially lower digesta viscosities were observed in chicks fed rye bread diets than in those fed rye wholemeals. 相似文献
143.
Debranning of wheat affects flour quality, initially by altering the breakage of wheat kernels during first break. The double normalized Kumaraswamy breakage function was applied to model the effect of debranning on wheat breakage during first break milling, in which type 1 breakage describes a relatively narrow distribution of midsized particles, whereas type 2 breakage describes a wide size range of predominantly small particles extending to very large particles. Mallacca (hard) and Consort (soft) wheats were debranned and milled at three roll gaps under sharp‐to‐sharp and dull‐to‐dull dispositions. Type 1 breakage increased at longer debranning times, whereas type 2 breakage decreased, for both wheat varieties under both dispositions. Sharp‐to‐sharp milling tended to produce more type 1 breakage than dull‐to‐dull. A mechanism of wheat breakage is proposed to explain the coproduction of very large and small particles via type 2 breakage and, hence, the effect of debranning. The proposed mechanism is that small particles of endosperm arise from scraping of large flat particles of wheat bran under the differential action of the rolls, such that removal of the bran reduces the production of the large bran particles and thus reduces the opportunity for the scraping mechanism that produces the very small particles. 相似文献
144.
R. Campbell 《Soil Use and Management》1990,6(4):173-178
Abstract. Biological control by manipulating agricultural practices has been used for thousands of years. In the more restricted sense, of adding antagonistic micro-organisms, biological control is still a very small part of the chemical pesticide market, but reliable products are becoming available. Achieving consistent results in realistic agricultural conditions is a problem, but there is a good possibility of controlling root diseases, especially where the soil characteristics or the environmental conditions can be controlled. The use of biological control in integrated control is successful, and in the long-term genetic engineering techniques will be important in the development of biological control. Environmental safety and effective patent protection are still being developed, but there seem to be no insuperable problems. 相似文献
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R E Ricketts D E Weinman J R Campbell M E Tumbleson 《American journal of veterinary research》1970,31(6):1023-1026
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T. M. Campbell P. M. Lording R. H. Wrigley R. B. Lavelle 《Australian veterinary journal》1980,56(12):593-598
SUMMARY Portal vein anomaly and associated hepatic encephalopathy was diagnosed in three dogs; a 2-year-old Old English Sheep Dog, a 14-week-old Old English Sheep Dog and a 20-week-old Corgi. The common clinical changes were anorexia, vomiting, depression, weakness and ataxia. The major laboratory findings were an elevated serum alanine amino transferase activity, hypoproteinaemia, hypoalbuminaemia, prolonged retention of sulphobromophthalein, fasting and postprandial hypeoammonaemia and ammonium biurate crystalluria. Angiographic studies demonstrated the presence of a patent ductus venosus in each case. The 2 Old English Sheep Dogs were destroyed at the owners' request and the necropsy findings in each case verified the presence of a portacaval shunt and hepatic encephalopathy. The Corgi is still alive, with conservative medical management, 28 months after the onset of signs. The dog is stunted and has mild, intermittent neurological disturbances. Clinical biochemistry indicates severe hepatic insufficiency and suggests a poor long term prognosis. 相似文献