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31.
32.
P.?N.?Mayamol T.?Samuel C.?Balachandran A.?Sundaresan C.?ArumughanEmail author 《Journal of the American Oil Chemists' Society》2004,81(4):407-413
Several pilot-scale trials reported in this paper, using palm stearin-rice bran oil (PS-RBO) blends, obviously did not contain
trans FA (TFA), whereas the commercial products were found to contain 18–27% TFA. The effects of processing conditions such as
rate of agitation, crystallization temperature, and composition of the blends on the crystal structure of shortenings were
studied. The products were evaluated for their physicochemical characteristics using DSC, X-ray diffraction (XRD), HPLC, and
FTIR techniques. The formulation containing 50% PS and 50% RBO showed melting and cooling characteristics similar to those
of hydrogenated commercial “vanaspati” samples. Analysis of the FA composition revealed that the formulated shortenings contained
15–19% C18∶2 PUFA. Tocopherol and tocotrienol contents of the experimental shortenings were in the range of 850–1000 ppm with oryzanol
content up to 0.6%. XRD studies demonstrated that the crystal form in the shortenings was predominantly the most stable β′
form, and there was less of the undesirable β form. 相似文献
33.
Yoshitsugu Kosugi Tsutomu Kunieda Naoki Azuma 《Journal of the American Oil Chemists' Society》1994,71(4):445-448
Rice bran oil containing 30–50% free fatty acid was continually converted to an oil containing more than 75% of triacylglycerol
(TG) by means of immobilized lipase. The reaction was carried out at 60°C for 24 h with dehydration and reactant mixing by
dry nitrogen flow under a positive nitrogen atmosphere. Enzymatic TG synthesis with evaporation by heating was not suitable
because of the increasing peroxide value of the oil.
Part of this article was presented at the annual meeting of the Japan Oil Chemists' Society at Sendai, Japan, October, 16,
1990. 相似文献
34.
R. F. Brennan 《Nutrient Cycling in Agroecosystems》1992,31(1):35-41
Five field experiments are described which measured the effect of take-all on grain yield of wheat when 5 levels of manganese fertilizer were applied in a factorial combination with 5 different types of nitrogen fertilizer.Ammonium nitrogen fertilizer, either as ammonium sulphate or ammonium chloride, lowered the severity of take-all. By contrast, sodium nitrate had no effect on the incidence and severity of take-all. Ammonium chloride and ammonium sulphate were equally effective at controlling take-all, suggesting that the chloride or sulphate ion had little or no effect on the disease.Manganese sulphate decreased take-all severity at two trial sites. Where manganese was deficient, an application of manganese lowered the severity of take-all, had no effect on the incidence and increased the dry matter and grain yields of the wheat plants. There were no beneficial effects of applied manganese if the wheat plants were adequately supplied with soil manganese.The results suggest that take-all is more severe where plants are deficient in either manganese or nitrogen. The work also suggests that manganese deficiency is not necessarily the reason why the wheat plants grown on the acid soils of south-west Western Australia are prone to take-all. 相似文献
35.
36.
系统粉粉色、麸星含量与面片色泽之间的关系 总被引:1,自引:1,他引:0
以小麦加工不同系统的20个粉样为原料,研究了系统粉粉色、麸星含量与面片色泽之间的关系.结果表明:麸星含量主要影响面粉的白度,对面片的色泽影响很小,面粉的白度与面片的色泽关系显著.面粉的色泽与面片色泽之间呈显著正相关,尤其是面粉的红度、黄度对面片的色泽影响极大. 相似文献
37.
Cr3+、Pb2+单一及复合胁迫对小麦种子萌发及幼苗脯氨酸含量的影响 总被引:2,自引:0,他引:2
研究在污染条件下小麦对重金属胁迫的反应,为农业生产中早期诊断重金属污染提供一些依据。用Cr3+、Pb2+及Cr3+、Pb2+混合溶液的各种浓度溶液处理小麦,研究Cr3+、Pb2+及Cr3+、Pb2+混合溶液对小麦萌发和脯氨酸含量的影响。结果表明:在Pb2+的培养环境中,各个浓度下的发芽率相差不多;在Cr3+的培养环境中,小麦的发芽率随着浓度的增加呈下降趋势,浓度越大对小麦发芽率的抑制作用越明显;在Cr3+、Pb2+混合的培养环境中,各个浓度下的发芽率随浓度的增加而呈降低的趋势,并且各个浓度下发芽率基本都相对低于相同浓度下的单一Cr3+、Pb2+的发芽率。在低浓度的重金属离子中,游离脯氨酸的含量与重金属离子浓度呈正相关。 相似文献
38.
In situ esterifications of high-acidity rice bran oil with methanol and ethanol and with sulfuric acid as catalyst were investigated.
In the esterification with methanol, all free fatty acids (FFA) dissolved in methanol were interesterified within 15 min,
and it was possible to obtain nearly pure methyl esters. The amount of methyl esters obtained from a given rice bran was dependent
on the FFA content of the rice bran oil. In the esterification with ethanol, it was not possible to obtain pure esters as
in methanol esterification, because the solubilities of oil components in ethanol were much higher than those in methanol. 相似文献
39.
R. Pandiselvam M.R. Manikantan V. Divya C. Ashokkumar R. Kaavya Anjineyulu Kothakota 《臭氧:科学与工程》2019,41(6):491-507
ABSTRACTOzone processing is one of the encouraging non-thermal and bio-friendly techniques in the food processing sector. The applicability of ozone technology in food industry is increasing due to its antimicrobial action and modification of functional properties of the foods. The structural modifications of starches have major applications in the food and bakery industry for producing products with increased shelf life, improved texture, and retention of moisture content. The positive response of ozonation in carboxyl and carbonyl group alters the viscosity of starch molecules. Rheological characteristics like low viscosity even at an increased concentration, desirable binding properties, and film-forming ability have increased its use in the food processing industry. The influence of ozonation in the physicochemical properties is mainly retrogradation and cross-linking of amylose and amylopectin molecules and enzymatic modifications. Ozonation cause change in crystallinity, viscosity, expansion ratio, and gelatinization temperatures. Finally, ozonation induces many possible changes in native starches for the effective utilization in the processing sectors. In this review, starch modifications utilizing ozone and various research achievements and scientific reports focusing on the effect of ozonation in terms of physical, chemical, and thermal properties of native starches and on the possible modifications have been summarized and discussed. In conclusion, ozone is a green technology that can be effectively used as an alternative oxidation technique for starch modification. 相似文献
40.
为探索知识图谱技术在农业智能生产中应用与落地, 解决复杂多样的农业生产数据的精准查询与可视化问题, 本研究以小麦品种知识为例, 利用爬虫技术, 爬取1852个小麦品种信息、735个微百科、102349个词条; 基于知识图谱技术, 设计品种知识图谱实体与关系, 对抓取数据进行清洗、抽取与融合, 经过实体识别、关系构造等处理, 构建实体258484个, 关系328933个. 在此基础上, 设计了小麦品种知识存储方式, 结构化数据存储在MySQL中, 非结构化数据存储在MongoDB中, 使用Neo4j图数据库存储知识图谱来提高知识的查询性能, 在此基础上实现小麦品种关系查询与实体识别, 提供品种数据精确表达与可视化, 表明利用知识图谱技术实现品种等信息的可视化是可行的, 该研究可以为知识图谱在农业中的应用提供技术参考和理论支撑. 相似文献