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损伤淀粉含量对米粉理化性质的影响 总被引:1,自引:2,他引:1
采用不同粉碎方法得到损伤淀粉含量不同的米粉,研究了损伤淀粉含量对米粉性质的影响。结果表明随着损伤淀粉含量的增加,米粉的总直链淀粉没有明显差异,可溶性直链淀粉和溶解度显著升高,溶胀度变化不大而透明度则显著降低。快速黏度分析(RVA)表明糊化温度由89.2℃降低到86.2℃,回生值由89.58 RVU降低到59.33 RVU,峰值黏度由139.29 RVU降低到85.08 RVU,谷值黏度由103.67 RVU降低到49.04 RVU,末值黏度由180.67 RVU降低到108.38 RVU。损伤淀粉含量9.05%米粉的衰减值最低。糊化后米粉凝胶的硬度和弹性显著降低。 相似文献
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物性处理对籼米粉及其淀粉回生的影响 总被引:1,自引:0,他引:1
研究了三次瞬时搅拌(方法A)和三次瞬时加热-搅拌(方法B)两种物性处理对籼米粉及其淀粉回生的影响,方法A即搅拌(500 r/min)20 s后加2 mL水,如此重复一次,最后再搅拌20 s,方法B与方法A不同的是边加热(100℃)边搅拌。结果表明,方法B处理能明显推迟籼米粉的回生。与空白样品(5.93J/干米粉g)和方法A处理的样品(5.08 J/干米粉g)相比,方法B处理的籼米粉有最低的回生焓值(3.04 J/干米粉g),但方法A和方法B处理对籼米淀粉的回生均没有影响。通过SEM观察发现,方法B处理能增大籼米粉网络结构的网孔,说明样品存在大量聚集水。籼米粉及其淀粉经过相同处理但得到的不同结果说明,方法B处理能使米粉中的米蛋白具有抗淀粉回生能力。 相似文献
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Christopher Mutungi Felix Rost Calvin Onyango Doris Jaros Harald Rohm 《Starch - St?rke》2009,61(11):634-645
Cassava starch was debranched using pullulanase and the linear glucans recrystallized by incubation at 60°C or by temperature cycling at 120/60°C, and further subjected to heat‐moisture treatment (HMT). Resistant starch (RS III) contents increased from 21.4 g/100 g in the debranched starch (DS) to 67.3 g/100 g in the debranched starch incubated at 60°C (DRS) and 47.8 g/100 g in the debranched starch subjected to temperature cycling (DCS), and further to 84.8 g/100 g and 88.4% g/100 g in HMT‐DRS and HMT‐DCS, respectively. Total crystallinity varied between 31.4‐59.8% and the crystalline type was C in DS and DRS and A in DCS, HMT‐DRS and HMT‐DCS. The melting properties were characterized by broad endotherms, but the exact melting region and enthalpy were dependent on recrystallization method. The main endothermic peaks of DS and DRS occurred at 103.9 and 109.8°C, respectively, whereas DCS exhibited split endotherms at 113.6 and 138.1°C. Heat‐moisture treatment broadened the endotherms and increased their enthalpies. Scanning electron micrographs revealed surface topography differences related to size and aggregation of individual crystalline bodies. 相似文献
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本文在实验室条件下采用酸湿热处理米粉样品,测定处理前后米粉的化学组成变化、颗粒形貌、结晶性质、红外图谱、热力学性质、糊化性质和消化特性。研究表明,经过酸湿热处理后的米粉蛋白质含量减少较多,其它的粗脂肪、还原糖变化不大。显微结构分析得出米粉保持原有的团粒结构,但偏光十字稍微变得模糊,颗粒的有序结构遭到一定破坏,少数淀粉脐点处出现凹坑。红外图谱变化不大,结晶度变小。处理后米粉的起糊温度升高,糊的峰值粘度降低,吸收焓减小。酸湿热处理可以一定程度下提高米粉中慢速消化淀粉(SDS)的含量。 相似文献
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芭蕉芋淀粉对米粉理化性质及粉丝品质的影响 总被引:1,自引:0,他引:1
将芭蕉芋淀粉和籼米粉按照一定比例复配并制作粉丝,以复配粉的溶胀性质、热特性、糊化特性、流变学特性为理化性质测定指标,以粉丝的质构特性、蒸煮性质、感官品质为其质量评价指标,考察了芭蕉芋淀粉对米粉理化性质和粉丝品质的影响。结果表明:随着芭蕉芋淀粉添加量的增加,复配粉的直链淀粉含量、膨润力、峰值黏度、最低黏度、降落值、糊化焓、回生焓、回生度、弹性模量、黏性模量增加,而溶解度、最终黏度、回升值、糊化温度逐渐降低;米粉丝的硬度、弹性、黏附性、咀嚼性随芭蕉芋淀粉添加量的增加而增大。与纯籼米粉粉丝相比,复配粉米粉丝的筋道感和柔韧度增强,其光滑度却下降。综合考虑,添加2%~5%芭蕉芋淀粉的米粉丝品质最佳,具有很好的可接受性。 相似文献
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Nispa Seetapan Nattawut Limparyoon Asira Fuongfuchat Chaiwut Gamonpilas Pawadee Methacanon 《International Journal of Food Properties》2016,19(7):1616-1630
Ice formation and non-freezable water (WNFW) of rice flour and tapioca starch gels were studied at two different freezing rates (–10 and –100°C/min) using differential scanning calorimetry. Ice crystal growth was observed in the slow freezing but not in the fast one. Ice melting enthalpies, however, were similar since more ice formed in holding and reheating steps. Melting enthalpy of fully gelatinized systems with water contents ~ 0.50–0.66 was associated to starch composition and granule morphology. Highly swollen tapioca starch gave the lowest enthalpy and the highest WNFW (0.40 g/g dry starch versus 0.32 and 0.38 g/g dry starch of normal and waxy rice flours, respectively). The further studies revealed that the WNFW values were associated to swelling power, solubility, and granule morphology. 相似文献
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为探究超声波处理对糯米全粉凝胶特性的影响及其作用机制,本实验以糯米全粉为原料,以反映凝胶黏弹性的损耗角正切值(tan δ)为优化指标,采用正交试验优化超声波处理糯米全粉的条件,得到最佳工艺参数为:超声波功率130 W、超声时间20 min、料液比1∶2,在此条件下糯米全粉凝胶的tan δ为0.82。通过扫描电子显微镜观察到原糯米全粉(waxy rice flour,WRF)中的淀粉颗粒团聚在一起,超声波处理糯米全粉(ultrasound treated waxy rice flour,UT-WRF)中的淀粉颗粒分散分布。UT-WRF凝胶的储能模量(G’)、损耗模量(G’’)、硬度、弹性均小于WRF凝胶,而峰值黏度和黏附性均大于WRF凝胶。淀粉作为糯米全粉的主要组分,质量分数达84.34%;分析从WRF和UT-WRF中提取的淀粉发现,两种淀粉的形态结构、糊化特性、冻融稳定性、流变学特性、质构特性均无明显变化。对比从UT-WRF与WRF中提取的蛋白质对比发现,UT-WRF中提取的蛋白质结构松散,孔洞密集,β-折叠与无规卷曲相对含量显著上升,二硫键含量以及热稳定性显著下降(P<0.05)。结论:超声波处理糯米全粉时,主要是通过改变其中第二大组分蛋白质基质的构象从而改变全粉的凝胶特性。 相似文献
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Rungtiwa Wongsagonsup Sujin Shobsngob Bovornlak Oonkhanond Saiyavit Varavinit 《Starch - St?rke》2005,57(1):25-31
Zeta potential (ζ) analysis was investigated as a means of rapid determination of residual protein content of rice flour during processing of rice starch. A rice flour sample was suspended in 0.3% sodium hydroxide solution to obtain rice flour slurry which was subjected to protein extraction by a decanter for five cycles. The samples from all cycles were collected, neutralized, dried, sieved through a 200 mesh sifter and subjected to ζ analysis. The data from ζ values (y) and chemical analysis of protein content (x) from six samples of rice flour were used in a regression analysis to develop an empirical equation to express the protein content of rice flour based on ζ value alone. The result of ζ value obtained from six samples of different protein contents suspended in a buffer solution of pH 12 yielded a standard linear equation of y = –1.29x–12.51. In another method of ζ analysis, the sample was suspended in DI (deionized) water without buffer by varying pH from 2 to 8 for the ζ measurement. A linear relationship between ζ and pH was obtained together with the constant value k (slope) which could be converted into protein content (x) of rice flour by a standard linear equation of k = –1.15x –4.90. 相似文献
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制粉工艺对大米粉淀粉成分的影响 总被引:1,自引:0,他引:1
采用不同制粉工艺制备大米粉并测定其中损伤淀粉和直链淀粉的含量,试验表明:与干磨制粉相比,湿磨制粉可以明显降低损伤淀粉的产生,且得到的大米粉中直链淀粉含量高,但磨浆却会导致部分可溶性直链淀粉流失。 相似文献
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小麦粉粒度变化与淀粉损伤程度 总被引:2,自引:0,他引:2
从小麦淀粉的原生态(粒径大小与分布)出发,首先拿等级粉的粗细度与之比较,分辨淀粉损伤的综合程度和倾向,进而对工艺中各研磨部位的面粉粒度、淀粉损伤程度进行分析研讨,以化验的量化结果,揭示淀粉损伤的真实面貌。紧紧抓住面粉粒度变化和淀粉损伤程度的同步因素,逐渐深入,诠释不被重视的等级粉淀粉损伤原因和专用粉能适应不同面制品要求的理论基础,提出了研究淀粉损伤和面粉粒度是制粉工艺研究的当务之急。 相似文献
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大米粉、大米淀粉及其磷酸酯淀粉的物性特征研究 总被引:1,自引:4,他引:1
利用快速黏度分析仪和质构仪测定了大米粉、大米淀粉及其磷酸酯淀粉的黏滞特性和质构特性,并用动态流变仪测定了大米粉、大米淀粉和磷酸酯淀粉糊的凝胶和回生。结果显示:磷酸酯淀粉的糊化温度显著低于大米粉和大米淀粉的糊化温度;磷酸酯淀粉抗老化性最强,不易回生,大米粉抗老化性最弱,易回生。大米淀粉经过磷酸酯化变性后,峰值黏度、崩解值和最终黏度增加,硬度、黏附性、弹性、胶黏性显著降低,凝聚性增强。在降温冷却过程中,大米粉的储存模量比大米淀粉和磷酸酯淀粉的储存模量增长速度快,大米粉和大米淀粉的损失因数降低,磷酸酯淀粉的损失因数升高。 相似文献
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Optimization of Gluten-Free Bread Prepared from Cornstarch, Rice Flour, and Cassava Starch 总被引:3,自引:0,他引:3
ABSTRACT: The proportions of cornstarch, cassava starch, and rice flour were optimized for production of gluten-free bread (with 0% and 0.5% soy flour) to maximize specific volume (Y1 ,Y1 '), crumb-grain score (Y2 ,Y2 '), and bread score (Y3 ,Y3 '). A central composite design involving cornstarch/cassava starch ratio (X1 ) and rice flour/cassava starch ratio (X2 ) was used, and 2nd-order models for Y1 and Y1 ' were employed to generate response surfaces. The maxima of response surfaces for crumb-grain score and bread score indicate that optimal gluten-free bread can be prepared from 74.2% cornstarch, 17.2% rice flour, and 8.6% cassava starch. Addition of soy flour at the 0.5% level also improved bread texture. 相似文献
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本文对稻米复配粉进行了干热改性,探究了干热处理对稻米复配粉及米蛋白性质变化的影响。实验结果表明,添加米蛋白后,稻米复配粉的峰值黏度降低,表明米蛋白降低了稻米淀粉的含量,产生了一定的稀释效应。干热处理后,稻米复配粉的黏度显著增加,表明干热处理使稻米淀粉与稻米淀粉或米蛋白之间通过非共价键或氢键产生相互作用。色差分析显示干热后的米蛋白明显偏黄。热重分析表明,130℃干热处理4 h后,米蛋白的起始失重温度由238℃增加到291℃,表明米蛋白的热稳定性显著增强。傅里叶红外光谱显示,干热4 h后的米蛋白在1250 cm-1处产生一个新的小峰,说明干热后的米蛋白有β-折叠结构发生改变,且在1600~1700cm-1处酰胺键振动增强,蛋白质的二级结构发生改变,表明干热促进了分子间的相互作用。 相似文献
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板栗淀粉的消化和回生性能制约着板栗食品产业发展,合理选择食品加工方法调控板栗淀粉的消化和回生性能对开发高品质营养健康的板栗食品具有重要意义。本文探究了普鲁兰酶酶解及耦合湿热处理对板栗淀粉的消化率、长期回生和多尺度结构的影响。结果显示,酶解处理增加了板栗淀粉的直链淀粉含量,改变了淀粉链长分布,提高了淀粉短程有序结构和结晶结构,从而降低了淀粉消化率;进一步的湿热处理促进淀粉链相互作用,提高了淀粉短程有序结构、结晶结构和纳米聚集体结构,导致了更低的淀粉消化率。在储存过程中,由于酶解导致更短的A链增加及易于重排的B1链降低,使得淀粉形成的结晶结构和纳米聚集体结构较少,从而降低了淀粉的回生程度;湿热处理促进了A链分子与其他分子的相互作用,加剧抑制淀粉分子重排程度,导致回生程度继续降低。因此,酶解耦合湿热处理可作为一种有效的调控淀粉消化和回生性能的方法,促进慢消化和低回生度板栗淀粉食品的开发。 相似文献
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将预糊化淀粉以不同的比例(0%~8%)分别添至糯米粉中,通过测定预糊化淀粉-糯米粉复合体系的糊化、流变特性并分析其微观结构,旨在改善糯米粉的加工及品质特性。结果表明:预糊化淀粉的添加能够显著提高糯米粉复合体系的峰值黏度、回生值、稠度系数(K)、触变回复率及弹性模量(G’),降低其损耗角正切值(tanδ),且随着添加量的增加,其凝胶结构特性变化更明显,从而证实了预糊化淀粉的添加有利于糯米粉形成稳定高的强凝胶结构。此外,预糊化淀粉的添加能够增强预糊化淀粉-糯米粉复合体系颗粒表面结构的致密性,提高其相对结晶度,从而有利于糯米粉糊形成三维网状凝胶结构,显著改善其凝胶性能。 相似文献