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51.
Oat roll is one of the traditional oat wholemeal foods. The purpose of this work was to investigate the effects of quick freezing at −20 °C, −40 °C and −80 °C for 90 min before frozen storage on the quality of frozen steamed oat roll. Quick freezing at −40 °C and −80 °C inhibited the increase of peak gelatinization temperature, enthalpy and the ordered degree of oat roll starch, therefore postponing starch retrogradation. The cross-section microstructure confirmed that reducing the quick-freezing temperature could prevent the increase of ice crystals size, ruptured structures and maintain the integrity of internal structure. As the storage time extend, the ice recrystallization led to an increase in size of ice crystals, while a decrease in their number. Frozen steamed oat roll starch had the highest swelling power at the quick-freezing temperature of −80 °C, that indicated strongest water absorption and binding ability when gelatinized again. Texture analysis demonstrated that hardness increased during frozen storage, quick freezing at −80 °C had the best texture properties. Therefore, declining the quick-freezing temperature could obtain a higher quality of frozen steamed oat roll, by means of delaying the starch retrogradation and minimising the size of ice crystals. 相似文献
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LV Li-hu LIU Xue-zhen ZHANG Ding-chao HU Yan-zheng LIU Peng LI Chi-bo ZHOU Qiang-an 《保鲜与加工》2004,(3):97-99
The paper expatiates the principle of the pilger mill roll groove. A math model for optimization is set up based on various factors concerning the roll groove including the deformation theory, design process and selection of the parameters, etc. Meanwhile, the CARD techniques are combined. As a result, a software for the roll groove optimization is developed that provides such functions as groove data management, groove profile plotting and groove data printing, being a basis for relevant technological decision and groove optimization. Meanwhile, the principle and realization of complex curves are discussed. The 3D modeling is achieved by the exchange of data that is based on the CARD system. 相似文献
54.
为了拓宽猕猴桃产品的开发途径,以猕猴桃、苹果为原料,研制猕猴桃—苹果复合果丹皮,最佳工艺配方为苹果与猕猴桃的质量比为2∶8,每100 g混合果浆里配料的添加量为:蔗糖30 g,柠檬酸4.5 g,果胶0.7 g,植物油0.5 g;最佳工艺条件为:50℃真空浓缩至可溶性固形物含量为50%左右,摊片厚度3~4 mm,50~55℃烘烤14~16 h。 相似文献
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The objectives of the present study were to determine the effect of ruminal dosing of mechanical stimulating brush (Rumen faibu; RF) on digestibility and on rumen fermentation status in Holstein steers fed high concentrate and low rice straw. Eight steers (461 kg in average bodyweight) were used. Four steers were orally dosed three RF per head (RF‐dosing) and the other four were not dosed (non‐RF). All steers were fed enough concentrate and rice straw to gain 1.4 kg/day in bodyweight. Rice straw was cut 2 cm and 30 cm. The organic cell wall content of feeding diets was 17% in dry matter basis. Digestibility and nutritive value were not affected by RF dosing and length of rice straw. Ruminal pH was significantly lower in RF‐dosing group than in non‐RF group after feeding, and tended to be higher in long rice straw than in short rice straw throughout the day. There were no clear difference on total volatile fatty acid concentration and molar proportion of volatile fatty acid by RF dosing and length of rice straw throughout examined period. These present results suggest that digestibility and rumen fermentation status are not affected by RF dosing when organic cell wall content of feeding diets is approximately 17% in dry matter with rice straw over 2 cm. 相似文献
56.
悬架的K&C特性对整车操稳性具有重要影响。基于悬架K&C试验台对试验车辆进行台架试验,根据拟合范围对试验数据进行后处理拟合。基于CarSim软件建立整车参数化仿真模型,分析不同关键参数的赋值对横摆角速度以及车身侧倾角的影响,得出整车操稳性的主要影响参数以及相应的影响规律,为工程实践中的悬架设计、整车底盘匹配提供一定参考。 相似文献
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芡实机械脱壳中的摩擦特性试验研究 总被引:1,自引:4,他引:1
为给芡实脱壳后的分离工艺和机械设计提供相关的物料性能数据,利用剪切仪、自制的斜面仪、休止角测定装置等设备,对不同成熟度、不同粒径大小的芡实颗粒的内摩擦系数、静滚动稳定角、休止角等摩擦特性进行了测定。结果表明,芡实颗粒越小、成熟度越低、接触表面粗糙度越大,则颗粒之间的摩擦力越大、颗粒与接触材料的摩擦力越大,其内摩擦系数、静滚动稳定角、休止角越大;利用斜度14.7~21.5°的斜面仪能够分离出芡壳,但不能对芡仁和带壳芡实整粒进行有效分离;采用橡胶板分离芡壳、芡仁效果最好。研究结果可为芡实脱壳、分离等相关机械的研发提供参考。 相似文献
60.
为了降低轮胎滚动能量损失,该文提出一种新型轮胎滚动阻力解析模型。分析轮胎滚动阻力产生的机理,考虑材料的弹性迟滞特点,定义非线性弹性力和非线性阻尼力构建轮胎垂向复合回复力公式,搭建特定试验进行模型参数辨识。根据刷子模型将轮胎接地部分化简为两部分:一部分为接地中心到刷毛单元开始接触地面的加载区域;另一部分为接地中心到刷毛单元离开地面的卸载区域。然后分别对参数辨识得到的加载和卸载曲线在相应区域内积分并求和,获得轮胎滚动阻力矩解析模型。根据ISO 28580标准对轮胎滚动阻力进行测试,结果表明:轮胎滚动阻力随速度(10~120 km/h)和垂向负载(6~25 kN)的增大而增大;试验结果与解析值在相同的工况条件下变化趋势基本一致,从而验证了模型的有效性。新型滚动阻力模型的提出有助于轮胎的结构优化。 相似文献