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1.
水相酶解法提取菜籽油与菜籽蛋白工艺的优化   总被引:11,自引:0,他引:11  
为提高菜籽蛋白的利用率,采用水相酶解法提取菜籽油与菜籽蛋白,以超滤法分离菜籽蛋白,重点对酶处理的工艺参数进行了研究。试验对各种酶的作用效果进行了比较,确定采用纤维素酶、果胶酶按活力比3∶1配方的复合酶处理效果较好;由优化试验得出酶处理的工艺参数为:固液比1∶5,酶用量30 U/g,酶处理时间100 min;在最佳工艺条件下获得高质量的菜籽油与菜籽蛋白,油与蛋白质得率分别为92.6%、82.3%。  相似文献   

2.
芝麻叶中总黄酮的最佳提取工艺研究   总被引:34,自引:1,他引:34  
该文测定了芝麻叶中总黄酮的含量,并对芝麻叶黄酮的提取工艺进行了研究。重点探讨了采用乙醇提取法和微波处理与乙醇提取相结合的方法提取芝麻叶黄酮类化合物的最佳工艺条件。试验结果表明:芝麻叶中总黄酮的含量为0.98%;乙醇提取法的最适工艺参数是浸提剂乙醇浓度为80%、浸提温度为80℃、料液比为1∶25、浸提时间为2.5 h,如此条件可使黄酮提取率达95.6%;微波处理与乙醇提取相结合的方法的最适工艺参数是微波功率200 W、微波处理时间70s,乙醇浓度为80%、浸提温度为80℃、料液比为1∶25、浸提时间为30 min,这种工艺可使黄酮提取率达95.8%。  相似文献   

3.
利用酒糟生物质发酵生产燃料乙醇的试验研究   总被引:19,自引:5,他引:19  
研究了采用固态发酵工艺利用酒糟生物质生产燃料乙醇的工艺。向酒糟生物质中加入0.05%液化酶,0.06%糖化酶,0.8%纤维素酶,0.4‰TH-AADY,调整酒糟生物质的酸度为3.0,含水率为60%,起始温度为22~24℃,发酵周期为9 d的条件下,燃料乙醇产率可达4.18%。中试结果表明,该工艺可正常生产燃料乙醇,产率为4.03%。本研究可以为酒糟生物质资源的合理利用、消除酒糟对环境的污染、开发可再生新能源提供一条新工艺。  相似文献   

4.
复合组织蛋白挤压加工工艺的初步研究   总被引:11,自引:2,他引:11  
该文利用FTS-50型双螺杆食品挤压机,进行了复合组织蛋白挤压加工工艺的研究。试验研究了各个工艺参数对产品组织化的影响,得出了较佳的工艺条件。结果表明:适量的油脂(2%~10%)可以降低主机功耗,并稳定组织化结构;原料的pH为6.5~7.5时,产品的纤维强度较好;淀粉添加量在10%以内,产品的纤维化结构明显而且口感适中;含水率和螺杆转速对挤压产品组织化质量有着复杂的影响;挤压变性段温度提高,产品的组织化程度提高。  相似文献   

5.
以猪脂肪、氢氧化钠、氯化钙为原料,在实验室条件下探索脂肪酸钙的加工工艺和加工过程。利用正交试验设计(L1645)对脂肪酸钙的加工工艺系数进行反复筛选,探索脂肪酸钙的最佳加工工艺参数。结果表明,脂肪酸钙的最佳加工工艺参数为氢氧化钠用量占脂肪重的27%、氯化钙用量占脂肪重的25%、皂化反应时间为5 h、复分解温度为90 ℃、用水量为脂肪的4倍。  相似文献   

6.
为提高马铃薯的利用率,丰富虾片品种,该文对马铃薯全粉虾片的加工技术进行了研究,结果表明,加工马铃薯全粉虾片的最佳工艺参数是:马铃薯淀粉与马铃薯全粉两者质量比为65∶35,粉团含水率为40%,老化时间16 h,50℃下干燥4.5 h,坯料含水率9%左右;油炸温度190~200℃。按此最佳工艺参数,加工过程中成型、蒸煮容易,所得产品马铃薯风味浓郁、口感细腻、膨胀度为362%。  相似文献   

7.
加工工艺对油茶籽油氧化稳定性及酚类物质含量的影响   总被引:4,自引:1,他引:3  
为了探究加工工艺对油茶籽油营养品质的影响,了解油酚类物质在加工工艺中的变化规律,该文从油茶籽油加工企业的生产线中取样,对压榨毛油和浸出毛油精炼工艺以及压榨毛油适度精炼工艺等不同工艺中油茶籽油中总酚、多酚组成及含量、抗氧化活性系数和油的氧化诱导时间等指标进行了测定。压榨毛油精炼工艺包括水洗、脱色、脱臭、冬化;浸出毛油精炼工艺包括碱炼、水洗、脱色、脱臭、冬化;压榨毛油适度精炼工艺包括脱胶、碱炼、水洗、冬化等工艺步骤。结果显示:压榨油茶籽毛油中总酚平均质量分数为103.06μg/g,显著高于浸出油茶籽油48.52μg/g(P0.05);油茶籽毛油经过精炼工艺后总酚和总酚的抗氧化活性均呈现下降趋势,三种精炼工艺后油茶籽油中总酚分别下降了88.9%,86.7%和63.81%,总酚的抗氧化活性分别下降了88.3%,93.51%和83.25%。适度精炼相比普通精炼对于保留油茶籽油中的多酚有明显优势,前者精炼后油茶籽油中总酚及其抗氧化活性系数分别为37.82μg/g和9.33%,后者仅为11.41μg/g和4.71%。通过高效液相色谱测定发现,浸出油茶籽毛油精炼后仅含有少量肉桂酸,压榨毛油传统精炼后压榨油茶籽油中测到苯甲酸、芦丁和肉桂酸等3种多酚的质量分数分别为4.7、1.58和0.22μg/g,压榨毛油适度精炼后的油茶籽油中测到了单宁酸、绿原酸、表儿茶素等9种多酚,其中单宁酸和绿原酸的质量分数最高,分别为4.57和3.26μg/g;适度精炼后油茶籽油氧化诱导时间从初始的8.56 h增加到11.66 h,增加了26.63%;压榨毛油传统精炼后油茶籽油氧化诱导时间从8.14 h增加到10.42 h,增加了21.83%。研究结果表明,压榨毛油适度精炼相比传统精炼工艺对于保留油茶籽油中多酚等成分有明显优势,所生产的茶油具有更强的氧化稳定性。研究结果为油茶籽油中营养成分的保留提供了途径,为油茶籽油加工工艺选择提供参考。  相似文献   

8.
废弃食用油脂两相厌氧发酵酸化条件优化   总被引:2,自引:1,他引:2  
油脂的水解和长链脂肪酸的降解是油脂厌氧发酵过程中的限速步骤,提高水解酸化阶段挥发性脂肪酸(volatile fatty acid,VFA)的产率,有助于后续甲烷化反应的进行。利用响应面方法(response surface methodology,RSM)对废弃食用油脂两相厌氧发酵水解产挥发酸条件进行优化,考察了初始p H值、原料负荷、反应时间和接种量对产生挥发酸浓度的影响,提出采用该工艺的数学模型及优化后的工艺参数。结果表明,各影响因子对挥发酸的影响顺序为:接种量反应时间原料负荷初始p H值,方程的F值为15.65,相关系数为0.9359,调整相关系数为0.8761,说明数学模型可以较好地模拟真实的反应曲面。优化得到最佳的工艺参数为初始p H值6.2、负荷300 g/L、反应时间8 d、接种量40%,在该条件下,实际产挥发酸7 221.0 mg/L,与预测值7 224.0 mg/L吻合且重现性较好。厌氧产甲烷试验表明,酸化后废弃油脂较未酸化油脂在甲烷产量、甲烷含量、总化学需氧量(chemical oxygen demand,COD)去除率及挥发性固体(volatile solid,VS)去除率方面分别提高了44%、11%、28%和51%,经酸化处理比未酸化油脂的厌氧发酵时间(完成一个厌氧发酵周期内总产气量的80%的时间)缩短了28%。该研究结果为废弃食用油脂的两相厌氧发酵中试提供了参考。  相似文献   

9.
Arcview在土地整理项目土方量计算中的运用   总被引:26,自引:5,他引:26       下载免费PDF全文
土方量计算是土地整理项目规划设计的重要内容之一,准确快速地计算土方量对开展规划设计、控制总投资及分配资金具有重要意义。该文应用数字高程模型(DEM)原理,对Arcview软件应用于土地整理项目土方量计算进行了探讨,并以河北省南宫市清凉江项目为具体案例介绍了计算的详细步骤。计算结果仅比经专家论证后批复的项目设计土方量大3.45%,说明该方法计算土方量是可行的。  相似文献   

10.
微波热风联合干燥工艺对枸杞品质和表面微生物的影响   总被引:3,自引:3,他引:0  
为明确微波热风联合干燥工艺对枸杞品质和表面微生物数量的影响,该文检测了微波热风联合干燥和传统热风干燥2种工艺各加工阶段枸杞的主要品质指标(枸杞多糖、总糖、粗蛋白、粗脂肪)和表面微生物数量,并对2种工艺的加工效果进行了比较。结果表明,采用微波热风联合干燥工艺和传统热风干燥工艺加工的枸杞,多糖和总糖损失率差异显著(P<0.05),联合干燥工艺较传统工艺分别降低了15.44和11.06个百分点,仅为18.46%和20.98%;粗蛋白损失率差异未达显著水平(P>0.05),损失率分别为21.46%和20.12%;粗脂肪损失率的差异也不显著(P>0.05),分别为10.56%和12.29%。在杀菌率上2种工艺差异显著(P<0.05),联合干燥工艺为91.26%,传统工艺为82.25%。干燥前的脱蜡处理具有杀菌作用,可杀灭65.24%的表面微生物。干燥阶段完成后,联合干燥工艺的杀菌率为91.26%,较传统工艺的杀菌率提高了9.01个百分点。在模拟大肠杆菌污染枸杞的试验中,脱蜡后喷菌的枸杞经2种工艺加工,联合干燥工艺的杀菌率为83.21%,较传统热风干燥工艺提高了12.93个百分点。因此,微波热风联合干燥工艺较传统热风干燥工艺更多地保留了枸杞的营养成分,杀菌效果更好,有利于枸杞干果的品质和食品安全。但是,对脱蜡后大肠杆菌污染的果实,微波热风联合干燥工艺和传统热风干燥工艺均不能彻底灭菌,需进行工艺改进或结合其他灭菌方法进行处理。研究结果可为微波热风联合干燥工艺在枸杞加工中的应用和改进提供参考。  相似文献   

11.
雷公藤提取农药用总生物碱工艺的优化(简报)   总被引:1,自引:0,他引:1  
为杀虫活性物质雷公藤生物碱的产业化开发利用奠定基础,以雷公藤根皮中总生物碱提取率为评价指标,综合考察pH值、提取时间、乙醇浓度、固液比和提取次数5个关键因素的影响,以L16(45)正交试验设计优选了雷公藤总生物碱的提取工艺条件,并利用人工神经网络进行仿真、评估和优化,最终获得了雷公藤根皮中总生物碱的提取优化工艺:根皮粉细度30目,pH2.5,固液比1︰10,乙醇浓度65%,提取时间2h,提取2次。该优化工艺条件不仅可减少成本,降低能耗,而且使雷公藤总生物碱提取率略有提高,在实际生产中具有较好的应用价值。  相似文献   

12.
Microbiological control of the biological decontamination of soils Five agricultural soils which were contaminated with n-tetradecane, 5-methyl-3-heptanone and naphthalene were used to follow the biological clean-up process of these soils. The hydrocarbon content, the microbial biomass (substrate-induced respiration), dehydrogenase activity and N-mineralisation were monitored for 20 weeks in the contaminated and control soils. Dehydrogenase activity followed similar patterns within various soils, the values being lowest at the beginning of the experiment and highest during the following weeks. N-mineralisation of four contaminated soils was reduced at the start of the experiment, but was increased afterwards. The influence of contamination on microbial activities was detected even after elimination of the hydrocarbons. The addition of compost of bark and pieces of bark increased the biological cleanup process of the Calcic Chernozem contaminated with 3,8% (w/w) fuel oil. The addition of both organic materials reduced the decontamination rate of the Haplic Chernozem. The ratio of N-mineralisation to microbial biomass of the Calcic Chernozem increased with the addition of compost of bark and pieces of bark, but decreased with the same treatment of the. Haplic Chernozem. The results of this study suggest that microorganisms immobilize nitrogen in the Haplic Chernozem ammended with pieces of bark to a great extent during the whole experiment. The high N-immobilization and the adsorption of hydrocarbons to the added organic material may be the main cause of the slow decontamination of the Haplic Chernozem.  相似文献   

13.
乙醇溶剂与超临界CO_2相结合提取高纯度卵黄磷脂的研究   总被引:5,自引:0,他引:5  
采用乙醇溶剂首先提取蛋黄粉中的卵黄油 ,然后用超临界 CO2 萃取方法脱除卵黄油中的中性脂肪 ,获得高纯度的卵黄磷脂。考察了工艺参数对提取效果的影响。试验表明 :在乙醇溶剂提取卵黄油阶段 ,乙醇浓度是影响卵黄油提取率的最主要因素 ,温度是影响卵黄磷脂提取率的最主要因素 ;在超临界 CO2 萃取阶段 ,磷脂的溶解度随萃取温度的升高而降低 ,中性脂质在 5 5℃时溶解度最大。采用此工艺 ,卵黄磷脂得率为 17.6 6 % ,纯度 94.41% ,且不含胆固醇。  相似文献   

14.
Batch experiments were performed to study metal sorption by pine bark and algae-treated bark. The biosorption of copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), cobalt (Co), and nickel (Ni) in synthetic multimetal aqueous solutions was studied as a function of metal content in solution, and amount and size of bark particles used for sorption. Influence of water hardness (Ca2+ only was tested) on the metal sorption process was also evaluated. Metal uptake from solutions with high heavy metal content (i.e. 10× the limit for leachate from landfills) was found to be independent of Ca2+ concentration. At low metal content in solution (i.e. 1× the limit for leachate from landfills), uptake of Cu, Zn, Ni, and Cd decreased with increasing Ca2+ content in water. Microalgae-treated bark was found to increase the metal sorption efficiency. Air-drying of bark-entrapped algae was shown to be the best method for sorbent drying. In general, the green algae, Chlorella sp. and Pseudokirchneriella subcapitata showed the best results in metal uptake. Sorption of Co, Zn, Ni, and Cd from solution with high levels of both heavy metals and calcium increased by almost 50% with algae treatment of bark was applied. At low levels of metals and calcium content, 100% uptake of Cu and Pb in water was observed. Uptake of other metals from solution with low metal and Ca content was relatively high (50–60%). Low pH (pH 3.0) had no influence on metal sorption from solutions with high metal content. For solutions with low metal content a decrease of metal uptake by 10–15% was observed for all the metals but Pb. Thus, the treatment of bark with microalgae was successful and influenced positively the uptake capacity of the bark.  相似文献   

15.
2,4,6-Trichloroanisole (TCA) is the compound most often associated with cork taint in wines and has been shown to have a very low sensory threshold ( approximately 5 ng/L in wine). A supercritical fluid extraction (SFE) method for TCA in bark cork stoppers was developed with quantification via gas chromatography-mass spectrometry with selected ion monitoring. Supercritical carbon dioxide functioned as the extracting solvent, and temperature and pressure were optimized for the extraction. The method was validated using the stable isotope (2)H(5)-TCA as the internal standard. Recovery of TCA from spiked corks was found to be within 1-4% of the theoretical concentration with a coefficient of variation ranging from 2.6 to 9.7%. TCA levels in corks pulled from wines described as tainted by experienced judges ranged from 0.13 to 2.11 microg/g of cork. The SFE procedure offers a rapid, quantitative, nearly solvent-free, and automated method for the extraction of TCA from complex solid matrices such as cork.  相似文献   

16.
Two large-scale national monitoring campaigns investigating changes in spruce bark extract acidity and long-term monitoring of bark acidity along elevation transects have been carried out in the Czech Republic. The investigations have revealed significant average changes in the pH values of bark extracts (4 g: 16 ml) from 2.35 to 2.60 between 1989 and 1995, and from 2.60 to 3.25 between 1995 and 2005. In comparison with 1990, the H+ concentrations in bark extracts had decreased by 10–15% in 1995 and by 70% in 2005. National emissions of acidic compounds were reduced by about 58% (1995) and 62% (2005), and the mean annual H+ deposition was reduced by about 60% (1995) and by about 80% (2005). However, neither inventoried current absolute amounts nor specific regional amounts of emitted acidic pollutants correlated significantly with bark acidity in 1995 and 2005. Bark acidity was not significantly affected by the elevation of the sampling plots or by the average tree defoliation. Along the altitudinal transects, considerably defoliated trees near the top of mountain ridges showed permanently lower bark acidity than trees lower down the mountain slopes. Significant differences in average bark acidity were found between defined mountain, highland and lowland elevation zones. In 2005, the epiphytic lichen Hypogymnia physodes was found at almost all sampling plots, with the exception of the most industrialised areas of two coal basins. The abundance of the lichen correlated significantly and negatively with spruce bark acidity and with total nitrogen and copper concentrations in moss growing at the bark sampling plots in 2005.  相似文献   

17.
为优化生物质流化床气化工艺,该研究在中试规模流化床实验台上进行了成型树皮和成型秸秆的空气气化试验,研究了空气当量比、气化温度与送风温度对成型树皮和成型玉米秸秆气化特性的影响,同时采用电子探针显微分析仪与X射线光谱分析仪对气化过程中结渣的微观结构与成分进行了分析。结果表明:气化效果随着空气当量比增大先升后降,空气当量比较佳值在0.24左右,此工况下树皮与秸秆合成气热值分别为5.66和3.92 MJ/m3,气化效率分别为59.62%与33.92%;气化温度增加促进气化效果提升,气化温度从700 ℃升高至800 ℃,树皮合成气热值与气化效率分别提升了1.01 MJ/m3与14.28%;一次风温度的提升对气化效果无显著影响(P>0.05),但明显提升了炉膛底部温度,容易导致结渣,不利于设备稳定运行。2种生物质都有明显结渣现象,其表面呈现熔融玻璃状。结渣主要由KAl(SiO3)、K2MgSi5O12等复杂化合物与SiO2组成。导致结渣的原因主要是生物质中K、Mg等碱金属元素在床料中富集,与石英砂床料反应形成低熔点熔融盐;树皮含有较多Ca,气化中形成高熔点的CaSO4进而抑制结渣,而秸秆成灰率高,含有较多的K,导致结渣更为严重。  相似文献   

18.
通过对河北省甘薯集中产区“一窝红”和“卢选1号”两个具有代表性的甘薯品种,在不同收获时间甘薯淀粉亩产量的试验测定,确定出该区甘薯用来制取淀粉的最佳收获时间。同时,为在甘薯最佳收获时间内制取淀粉,提高甘薯淀粉的亩产量,研究设计了适合甘薯集中产区的6SF-20型薯类磨浆分离机。该机的淀粉分离率为96.4%,淀粉提取率为92.0%,达到国际先进水平  相似文献   

19.
酶解法提取黑木耳中胶原蛋白的工艺优化   总被引:1,自引:1,他引:0  
为了提高提取黑木耳中胶原蛋白得率,研究黑木耳中胶原蛋白提取工艺路线优化酶法提取的最适条件,采用单因素试验与多元线性回归试验设计相结合的试验方法,经过数据计算统计分析,由回归方程可知,在一定范围内得率与pH值呈正相关,与液料比呈正相关,与酶添加量呈负相关,与酶解时间呈负相关,得出优化工艺参数为:采用胰蛋白酶,酶解pH值为8.0,液料比为52.5:1mL/g,酶添加量为8%,酶解时间为2h,其中在此条件下从黑木耳中提取胶原蛋白得率达到1.091%。研究结果为植物性胶原蛋白制备提供了参考。  相似文献   

20.
Aspen bark was investigated for photosynthetic function, pigment content, and spectral characteristics during the 1993–1994 Boreal Ecosystem-Atmosphere Study (BOREAS) summer field campaigns in the boreal zone of Saskatchewan, Canada. Parameters related to photosynthetic function were similar for bark and leaves: chlorophyll (Chl) concentration; fluorescence responses; and spectral reflectance. Similar increases along a vertical gradient from base to tree top were observed for incident photosynthetically active radiation (PAR), photosynthetic pigment content, photosynthetic capacity, and spectral reflectance variables. Since transmittance of aspen bark periderm was 20–30% in the blue, and 50–60% in the red Chl absorption bands, the PAR available to the photosynthetic cortical layer in the natural, canopy environment (<1000 μmol m?2 s?1) was sufficient to support positive net assimilation (<8–10 νmol CO2 m?2 s?1) under ideal conditions (e.g., light, temperature, saturating CO2), a rate approximately 30–50% that of leaves. However, the respiring tissues comprising the greater fraction of bark tissue bias the balance of CO2 exchange in favour of respiration for the whole bark. Therefore, net photosynthesis under ambient conditions on the whole bark was, in general, negative. The total bark surface area was estimated to contain 17–40% of the whole tree Chl. The contribution of the bark surface area fraction of the full canopy (leaves plus bark) increased with age (<60 years), with a similar trend expected for bark in total tree (and stand) photosynthesis. A spectral reflectance variable, the red edge inflection point (REIP), was related to total bark Chl content (r2=0.74). A better predictive relationship (r2=0.82) for total bark Chl was observed using a spectral index calculated from the reflectance ratio of two narrow wavebands (R3/R2: R2 and R3 are between 0.715–0.726 μm and 0.734–0.747 μm, respectively), which may have greater utility in landscape remote sensing. The bark spectra for Chlcontaining bark should improve understanding of carbon balance in aspen forests, based on landscape-level radiative transfer simulations.  相似文献   

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