首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
对米糠油进行脱蜡和磷酸-草酸辅助水化脱胶,再联合碱炼脱酸、蒸馏脱酸两段脱酸工艺进行脱酸,研究碱炼脱酸保留酸价以及两段脱酸工艺对谷维素留存率的影响。以谷维素含量、脱酸率、精炼率为考察指标,在单因素试验的基础上采用响应面试验优化脱酸工艺。结果表明,原油酸价(KOH)为22~25 mg/g时,碱炼脱酸保留酸价(KOH)取5 mg/g,原油酸价(KOH)为27~33 mg/g时,保留酸价(KOH)取6 mg/g,原油酸价(KOH)为35~37 mg/g时,保留酸价(KOH)取7 mg/g,谷维素留存率较高。米糠油碱炼脱酸的最佳工艺条件为温度25℃,时间22 min,碱液质量分数16. 91%,加碱量为理论碱量加0. 1%的超碱量;蒸馏脱酸的最佳工艺条件为温度225℃,时间86 min,真空度0. 098 MPa。在最佳工艺条件下,碱炼脱酸后谷维素含量为2. 05%,脱酸率为77. 78%,精炼率为80. 05%;蒸馏脱酸后谷维素含量由2. 05%升高到2. 16%,接近原油(2. 15%),脱酸率为90. 83%,精炼率为92. 42%。  相似文献   

2.
以乳木果液油为原料,经甲酯化后得到低酸值的乳木果液油,通过转酯化把甘三酯转化为脂肪酸甲酯,通过分子蒸馏把脂肪酸甲酯和生物活性物质分为轻组分和重组分,重组分(生物活性物质)再经过溶剂结晶进一步提高生物活性物质含量。通过单因素实验确定较好的甲酯化工艺条件为:反应温度70℃,反应时间3 h,醇油质量比3∶10,浓硫酸添加量3%;在此条件下,乳木果液油的酸值(KOH)从56.1 mg/g降至2.1 mg/g,游离脂肪酸转化率达到96.3%。通过单因素实验确定的较佳分子蒸馏条件为:进料速率2 m L/min,刮膜转速250 r/min,蒸馏温度150℃,真空度0.1 Pa;在此条件下蒸馏,生物活性物质在重组分中的回收率达95.9%,生物活性物质含量可达68.8%。乳木果液油经过甲酯化、转酯化、分子蒸馏和结晶得到的产品中三萜醇和甾醇总含量可达69.80%,生物活性物质含量可达83.18%。  相似文献   

3.
研究了影响分子蒸馏脱除深海鱼油游离脂肪酸的因素,并确定了最佳工艺条件。通过单因素实验分析影响分子蒸馏脱酸效果的主要因素为蒸发面温度、刮膜转速、进料速率和真空度,结合工业化生产实际,应用正交实验优化工艺条件为:预热温度50℃,冷凝温度30℃,蒸发面温度175℃,进料速率2.5 mL/min,刮膜转速80 r/min,真空度3.5 Pa。在优化工艺条件下,产品酸值(KOH)为0.98 mg/g,脱酸率可达94.5%。  相似文献   

4.
本文采用分子蒸馏技术脱除餐厨油脂中的游离脂肪酸制备饲用油脂,研究了分子蒸馏温度对饲用油得率、酸值、过氧化值及丙二醛含量的影响。结果表明:在蒸馏温度为140℃、压力为1.0Pa、刮膜速率为250r/min下分子蒸馏餐厨油脂,可得到酸值为6.74(KOH)/(mg/g)、过氧化值3.70mmol/kg、丙二醛含量为2.63mg/kg的饲用油,得率为72.68%。  相似文献   

5.
为了得出分子蒸馏法脱出核桃油毛油中游离脂肪酸的最佳工艺,在单因素(进料速度、蒸馏温度、刮膜转速)分析基础上,运用BBD设计进行响应面分析,得出了因变量二次回归方程,并得出最佳工艺条件:进料速度250 g/h、蒸馏温度180℃、刮膜转速250 r/min。试验证明,此工艺条件可以使核桃油毛油酸值降至0.6 mg KOH/g以下,且维生素E等功效成分未破坏,过氧化值未升高,可达到1级核桃油标准对游离脂肪酸的要求。  相似文献   

6.
以菜籽油为原料,模拟出高酸值植物油,分别采用两次碱炼脱酸法、乙醇溶剂多次萃取法和分子蒸馏-碱炼脱酸法进行脱酸,探讨模拟高酸值菜籽油碱炼最大脱酸程度及该脱酸程度下最佳脱酸方案,最后应用于高酸值薏米米糠油进行验证。研究结果表明,模拟高酸值菜籽油碱炼脱酸的最大脱酸程度为60 mg KOH/g; 3种方法经优化后,两次碱炼脱酸后精炼油酸值为0. 111 mg KOH/g,总得率为34. 82%;乙醇萃取脱酸后精炼油酸值为3. 158 mg KOH/g,总得率为47. 77%;分子蒸馏-碱炼脱酸后精炼油酸值为0. 280 mg KOH/g,总得率为57. 45%。最佳脱酸方案为分子蒸馏-碱炼脱酸,其工艺为:在蒸发器温度165℃、内冷器温度30℃、转速365 r/min条件下分子蒸馏后,采用60 g/L的NaOH溶液在0℃下脱酸,100 g/L的Na Cl溶液洗脱皂脚后分离得最终脱酸油。高酸值薏米米糠油经最佳工艺脱酸后,其酸值由63. 41 mg KOH/g降至0. 441 mg KOH/g,总得率为57. 05%。实际体系和模拟体系脱酸结果一致性较好,说明模拟所得最佳脱酸工艺具有可行性。  相似文献   

7.
为得到高纯度的甘油二酯产品,利用分子蒸馏技术对酶催化合成的甘油二酯进行脱酸和纯化。在分别考察进料速率、蒸发面温度和刮板转速对分子蒸馏效果影响的基础上,正交试验得到最佳工艺条件及结果为一级分子蒸馏进料速率2 mL/min、蒸发面温度170 ℃、刮板转速300 r/min,此时纯度达72.51%;经二级分子蒸馏后产品纯度92.31%、酸值0.97 mg KOH/g。与大豆色拉油相比,蒸馏后甘油二酯的硬脂肪酸含量升高,稳定性好,碘值、皂化值和过氧化值降低。  相似文献   

8.
为了提高核桃油产品品质,采用分子蒸馏法对核桃油中的游离脂肪酸和塑化剂(DBP、DEHP、DINP)进行脱除,并兼顾营养物质的保留。通过单因素实验和正交实验对核桃油中脱酸、脱塑条件进行优化。结果表明:进料速率和蒸馏温度对营养物质和DBP的影响较为显著,蒸馏温度和刮膜转速对于游离脂肪酸和DEHP的脱除影响更大;最佳脱酸、脱塑工艺条件为真空度0.1 Pa、蒸馏温度170℃、进料速率600 mL/h、刮膜转速350 r/min,在此条件下核桃油酸值(KOH)由1.08 mg/g降为0.057 mg/g,DBP含量由1.54 mg/kg降为0.12 mg/kg,DEHP含量由4.83 mg/kg降为0.98 mg/kg,DINP均为未检出,维生素E及甾醇的综合保留率达到82.77%。综上,所优化的条件可以将塑化剂含量降至标准要求范围内,可大幅降低酸值,且较好地实现了对维生素E和甾醇的保留。  相似文献   

9.
对分子蒸馏技术精制灵芝孢子油的工艺条件进行了研究,考察了分子蒸馏工艺参数对降低灵芝孢子油酸值和过氧化值的影响.通过单因素和正交实验确定的最佳工艺参数为:蒸馏温度200℃,进样速率2 mL/min,刮板转速160 r/min,冷凝温度50℃.在最佳工艺条件下,灵芝孢子油酸值(KOH)从17.00 mg/g降到0.40 mg/g,过氧化值从25.87 meq/kg降到5.21 meq/kg,总三萜化合物含量从3.01%降到2.87%,在可以接受的范围内.  相似文献   

10.
采用分子蒸馏技术进行稻米油脱酸研究。在单因素试验的基础上进行Box-Behnken响应曲面试验设计,重点考察温度、转速和进料速度对酸值的影响,得到分子蒸馏脱酸最佳操作条件及二次响应面模型,最佳工艺条件为温度208℃、转速183r/min、进料速度2.05mL/min,此时所得酸值为1.01mg/g KOH。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

13.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

14.
15.
16.
This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

17.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

18.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

19.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

20.
《印刷工业》2014,(12):102-103
Sponsored by Printing and Printing Equipment Industries Association of China (PEIAC) and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference (INFOPRINT 2014) was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号