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81.
研究添加魔芋胶与瓜尔豆胶对鸭血豆腐食用品质的影响。以新鲜鸭血为原料,添加魔芋胶和瓜尔豆胶为 稳定剂,凝血10 min,90 ℃加热40 min制成鸭血豆腐。测定鸭血豆腐的离心损失、蒸煮损失、析水率、色泽和质构 等指标,并进行感官评定。结果表明:单独添加魔芋胶或瓜尔豆胶均能降低鸭血豆腐的离心损失、蒸煮损失和析 水率,同时改善产品的质构;当魔芋胶和瓜尔豆胶以质量比7∶3进行复配,在生产鸭血豆腐时添加量为4.0 g/L时, 其效果达到最佳,能够显著改善鸭血豆腐的亮度(P<0.05),硬度、弹性、胶着性和咀嚼性等质构特性也明显提 高,感官上切面光滑均匀,呈红褐色,孔隙少且细小。因此,魔芋胶与瓜尔豆胶复配添加具有协同稳定作用,能够 显著改善鸭血豆腐的食用品质。 相似文献
82.
83.
In this study, the physical properties of sisal and coir fibers have been described. Using manual extraction procedures, the sisal fibers were extracted from the sisal plant and coir fibers from the coconut palm. Thermal analysis by differential scanning calorimetry, structural morphology by scanning electron microscopy, and the degree of sharpness of the equatorial reflections of the X-ray fiber diffraction pattern were recorded for the untreated sisal and coir fibers. Tensile strength was determined for the single fiber and the results are correlated with the tensile strength of bundle fibers. Composite material has been prepared with this plant fiber as a filler and tamarind seed gum as a matrix material. The endosperms of roasted tamarind seeds were used for the preparation of tamarind seed gum solution. The different temperature condition maintained for roasting the seeds are 130°C, 160°C, and 180°C. The tensile strength of the prepared composite material is measured and it shows dependency of the roasting temperature condition of the tamarind seed. Scanning electron microscopy and water resistivity test were conducted, and the results were reported for the prepared composite material. Low-cost housing is made using this biodegradable sisal fiber--tamarind seed gum composite material. 相似文献
84.
瓜尔豆胶对锥栗淀粉糊化和流变学特性的影响 总被引:2,自引:0,他引:2
以新鲜锥栗为原料,考察了瓜尔豆胶对锥栗淀粉的糊化特性和流变学特性的影响。结果表明,向锥栗淀粉中添加瓜尔豆胶后,锥栗淀粉糊化溶液的峰值黏度和终值黏度增大,且随瓜尔豆胶添加比例的增加而增大;添加瓜尔豆胶增大了锥栗淀粉的起始糊化温度和峰值糊化温度,提高了锥栗淀粉的吸热焓,使得糊化过程更长,吸热更多。添加瓜尔豆胶后的锥栗淀粉溶液显示为假塑性流体,剪切变稀现象更为明显,具有更大的黏弹性。添加瓜尔豆胶后,混合物形成的凝胶表面空隙中填充物增多,空隙数量减少,且空隙分布更加均匀。 相似文献
85.
以海藻酸钠(SA)与阿拉伯胶(GA)为载体固定化酸性蛋白酶,以酶活回收率为评价指标,在单因素试验基础上,通过正交试验优化固定化条件。得到以SA-AG复合凝胶为载体制备固定化酸性蛋白酶的最佳工艺条件为:复合凝胶质量浓度3.5 g/100 mL,SA与AG质量比2∶1,氯化钙质量浓度7.0 g/100 mL,固定化时间1.0 h,给酶量1 540 U/g,吸附时间2.0 h,酶液pH值为3.0。此最佳条件下,固定化酸性蛋白酶酶活回收率为67.34%,酶活力为1 380 U/g。固定化酶酶学性质的研究结果表明,固定化酸性蛋白酶的最适作用温度(45 ℃)和最适反应pH值(pH=3)均与游离酶相同,但其热稳定性优于游离酶,且随着温度的升高这种优势越明显。 相似文献
86.
Influence of guar gum addition on physicochemical,microbial, rheological and sensory properties of stirred yoghurt 下载免费PDF全文
This study investigated the effects of adding guar gum (0, 0.6 and 0.8 g/100 mL) on the physicochemical, microbial, rheological and sensory properties of stirred yoghurt. Incorporation of guar gum into the yoghurt significantly affected the pH and colour, but did not significantly influence the lactic acid bacteria counts. The magnitudes of apparent viscosity (ηa,100), consistency index (K), yield stress (σoc), storage modulus (G′) and loss modulus (G″) for yoghurt samples containing guar gum (0.6–0.8 g/100 mL) were significantly greater than those for the control (without guar gum), indicating that guar gum can improve the steady and dynamic shear rheological properties of yoghurt. 相似文献
87.
从天然原桃胶分离到1 株产抑菌活性物质的芽孢杆菌TJ12。其发酵产物对金黄色葡萄球菌(Staphylococcusaureus)、藤黄微球菌(Micrococcus luteus)、蜡样芽孢杆菌(Bacillus cereus)和串珠镰刀菌(Fusarium moniliforme)有抑菌活性。结合菌落形态、生理生化指标、16S rRNA序列和gyrB序列将TJ12菌株鉴定为地衣芽孢杆菌(Bacillus licheniformis)。通过硫铵沉淀、有机溶剂萃取、羟丙基葡聚糖凝胶、高效液相色谱分离纯化,得到其主要活性物质。该物质对pH值、温度和3 种蛋白酶(胰蛋白酶、蛋白酶K、胃蛋白酶)有较好的稳定性。经电喷雾电离质谱分析,初步鉴定该株地衣芽孢杆菌TJ12的主要抗菌物质为杆菌肽A。 相似文献
88.
多糖作为非极性矿物表面抑制剂应用非常普遍,但关于其抑制机理和影响其抑制的因素研究还未完善。将国内外有关采用糊精、羧甲基纤维素(CMC)、木质素磺酸盐及古尔胶抑制滑石和辉钼矿的研究进行了总结,介绍了多糖抑制剂抑制非极性表面的研究进展,并从浮选分离滑石和辉钼矿的角度分析了这4种有机抑制剂对这2种矿物抑制的影响因素和抑制效果。研究表明,多糖的抑制效果不仅与矿浆的pH值、离子强度和离子种类有关,还与多糖分子的特性有关;在2种矿物的浮选分离方面,除了木质素磺酸盐能够高效率地分离滑石和辉钼矿外,十二烷在辉钼矿表面的吸附可有效阻止木质素磺酸盐的吸附,使木质素磺酸盐也可能成为滑石和辉钼矿有效分离的抑制剂;多糖对2种矿物的抑制不能仅从吸附量方面阐释,更重要的是多糖吸附层的特性;关于多糖的吸附机理则存在争议,主要有疏水力论、静电力论、化学力论、氢键和羟基作用论,或它们的综合作用论。 相似文献
89.
Sabyasachi Swain 《国际聚合物材料杂志》2019,68(5):256-265
A series of microwave irradiated IPN of Crg and GG have been synthesized and cross linking through hydrogen bonding was confirmed by FTIR spectroscopy. Thermal sensitivity at 48°C, degradation above 200°C is an emblem of uniqueness. We obtained micro rough surface morphology, hydrophilicity and muco-adhesion supporting S6 for targeted drug delivery. Honey comb like internal architecture will provide high mechanical strength. The sample S6 showed 72% drug release in 12 hours. Based on the results, it was concluded that the S6 can be used as target oriented controlled drug delivery devices enabling control over swelling and drug release. 相似文献
90.
In this study, gum arabic powder was produced according to four methods by inserting a restructuring stage by DIC treatment (instant controlled pressure drop) in the classic process of grinding and spray drying. Properties of the final product were compared, and the results show that DIC treatment enables to control and improve the properties of the powder. The DIC treatment can cause a controlled increase in the tapped bulk density, filling rate, compressibility, porosity; and a reduction in interstitial air volume and the loose bulk density. It also facilitated the subsequent grinding and intensified the drying kinetics. The impacts of pressure and DIC treatment time were examined. Pressure was the strongest factor influencing the properties of the gum arabic powder. Selecting an optimal pressure and treatment time plays a decisive role in controlling the properties of powders. 相似文献