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11.
枸杞的微波干燥特性及其对品质的影响 总被引:2,自引:0,他引:2
为了缩短枸杞的干燥时间、节约干燥成本,运用微波试验装置,通过选择不用的干燥功率和物料铺放厚度,研究了枸杞微波干燥特性及其对干燥后产品品质的影响。研究结果表明:微波干燥作用于枸杞干燥降速干燥阶段可以大幅缩短枸杞干燥周期,微波组合干燥较自然晾晒缩短时间约65h,约占自然晾晒干燥周期的72%;干燥功率和物料层厚度是影响微波干燥时间的重要因素,微波功率越大,物料层厚度越小,则物料干燥时间越短;不同的微波干燥参数对干后产品品质有不同影响,微波功率为1k W,当物料层厚度平铺为2cm时,干燥后产品多糖保存率和感官品质最好。 相似文献
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With the goal of the sintering of magnetite concentrates without carbon,the effect of quality,inert atmosphere and Fe_3O_4 addition on microwave sintering of magnetite concentrates is studied.It is shown that: With the same basicity(CaO/SiO_2=2.5) and microwave heating condition(1000W,2.45GHz,20min),the centre temperature decreaseds with a increasing sample mass;There is no great difference between with and without inert atmosphere in microwave sintering of magnetite in a same microwave heating condition.When 100g sample(CaO/SiO_2=2.5) is heated by microwave irradiation(1000W,2.45GHz,20min),the more Fe_3O_4 is added,the less liquid phase is produced,which is bad for microwave sintering of magnetite concentrate. 相似文献
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Novel surface treatment technique by silane film is developing for metallic anti corrosion and coat improvement. The key points, hydrolysis and condensation, for the stability of the Silane agent(SA) solution is investigated, and the effective factors of stability for silane agent solution and the relative rule are discussed. It is found that stability of SA solution is related to the temperature, pH, solvents, SA concentration and additive by studying the state of the solution and the conductivity-time curve of SA solution. Meanwhile, controlling factors and improving methods for SA stability are proposed to guide the practical application of metallic surface anti-corrosion treatment by SA. 相似文献
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微波加热对米糠储藏性能和蛋白质溶解性的影响 总被引:3,自引:0,他引:3
研究了微波加热对于米糠5周储藏期间酸值和过氧化值及米糠蛋白溶解性的影响。结果表明,利用微波加热稳定米糠,可以有效降低酸值,防止水解酸败,同时也能降低过氧化值。 相似文献
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Methyl anthranilate (MA), a food grade flavor and fragrance additive, has been reported to be an effective non-lethal bird repellent in a variety of situations. Despite the experimental success of MA, field studies have yielded widely differing levels of efficacy. Diminished efficacy in some field trials probably results from the failure of specific formulations to retain or protect the active ingredient under natural conditions. Therefore, a clearer understanding of the physical and chemical factors affecting the stability of MA is needed. We undertook a series of laboratory studies on hydrolysis, photolysis and microbial degradation of MA, the results of which could be useful in the development of appropriate formulation strategies and residue analyses. We found the n-octanol:water partition coefficient, (P) to be 84. MA is not subject to hydrolysis at 25°C in phosphate buffer media at pH 5·0, 7·0 and 9·0. MA slowly photodegrades under simulated UV ‘sunlight’. Forty-four percent of MA is lost after 432 h illuminance at 1·25 mW cm−2, which is equivalent to approximately 1200 h natural sunlight (40°N, noontime, June). Kinetic data indicate that the initial step of photolysis, subsequent to excitation, is a second-order reaction with respect to MA. A major photodegradation product appeared in an amount of about 10% of the mass balance and was determined to be an oxidized trimer of MA. MA is primarily affected by aerobic microbial degradation. For a 12:12 h light:dark, under laboratory illumination, 12% of water-solubilized material can be lost in the first seven days. Losses were 30% and 42% at 16 and 27 days, respectively. Under conditions of optimal bacterial growth (warmth and darkness) loss of MA was 22% at nine days and 100% by 20 days. The susceptibility of MA to microbial degradation is promising for the prospects of developing formulated, environmentally safe, bird repellents. 相似文献
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扇贝加工废弃物蛋白酶解及其酶解产物分子量分布的研究 总被引:5,自引:1,他引:4
对用复合酶酶解扇贝加工废弃物制备水解蛋白的工艺进行了研究,通过正交试验方法确定了用两种复合酶酶解的最适水解条件。结果表明,用枯草杆菌中性蛋白酶和风味酶复合酶酶解的最佳酶解参数为:加酶量比为2∶1,温度为65℃,pH为7.0,时间为5 h,水解液氨基酸态氮含量为50.3%,蛋白质水解度为95.5%。用木瓜蛋白酶和风味酶复合酶酶解的最佳酶解参数为:加酶量比为2∶1,温度为65℃,pH为7.0,时间为5 h,水解液氨基酸态氮含量为43.2%,蛋白质水解度为85.0%。用SephadexG-15葡聚糖凝胶柱层析法对水解产物的分析结果表明,两种混合酶的酶解产物为蛋白肽和游离氨基酸,其相对分子质量均集中分布在585和150左右。 相似文献
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