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1.
核桃油微胶囊化工艺的研究   总被引:21,自引:6,他引:21       下载免费PDF全文
为了防止核桃油的氧化,扩大核桃油的用途,用分子络合、乳化包埋、复凝聚等方法对超临界CO2流体萃取的核桃油进行了微胶囊化研究,以确定产品的最佳生产工艺条件。试验结果表明:采用喷雾干燥法,以大豆分离蛋白和麦芽糊精、β-环状糊精和阿拉伯胶、明胶和阿拉伯胶为壁材,均可制得高质量高包埋率的核桃油微胶囊产品;喷雾干燥法制备核桃油微胶囊适宜的工艺参数为:进料浓度20%~30%,进料温度50~60℃,进风温度160~180℃,出风温度70~80℃。  相似文献   

2.
花椒油树脂微胶囊的制备   总被引:2,自引:0,他引:2  
为了将黏稠的花椒油树脂制备成具有良好分散性、流动性和耐储存的微胶囊,该文采用喷雾干燥法研究了花椒油树脂微胶囊工艺,通过单因素实验和正交实验确定花椒油树脂较好的工艺条件为阿拉伯胶:麦芽糊精的配比为1:4,芯壁的质量比为1:6,胶液浓度为30%.乳化液在40℃、40 MPa条件下均质2次.喷雾干燥参数:进气量9 m3/min、进料速度8 mL/min、进风温度140℃、出风温度70℃时,在此工艺条件下制备的微胶囊包埋率可达92%,且品质较好.  相似文献   

3.
猕猴桃籽油微胶囊化技术研究   总被引:17,自引:4,他引:17       下载免费PDF全文
猕猴桃籽油中不饱和脂肪酸含量较高,特别是亚麻酸含量高达63.99%.为防止猕猴桃籽油的氧化,采用喷雾干燥法对猕猴桃籽油进行微胶囊化研究,并对产品进行了电镜观察和氧化试验.结果表明:壁材采用1∶1的大豆分离蛋白与麦芽糊精,芯材与壁材的配比为1∶1.5,料液总固形物含量为25%,在30~35 MPa压力下均质处理,喷雾干燥进风温度180℃,出风温度80℃,制得的微胶囊结构理想,抗氧化性较好.  相似文献   

4.
柞蚕粉微胶囊化制备工艺的研究   总被引:1,自引:0,他引:1  
为了更好得开发利用柞蚕资源,该文通过对微胶囊壁材的初选试验和包埋工艺的研究,确定了以spo-mo350变性淀粉、阿拉伯胶做为壁材,以柞蚕粉做为芯材,利用喷雾干燥的方法制备柞蚕粉微胶囊。通过正交试验确定微胶囊包埋最佳工艺参数为:spo-mo350变性淀粉/阿拉伯胶的质量比为4∶1,进风温度180℃,出风温度115℃,芯材/壁材的质量比为1∶1,壁材占乳化液比例30%,包埋率达86.4%。该微胶囊包埋工艺能够较好的解决柞蚕粉存在的腥味重、易氧化等问题,使其具有更广阔的应用前景。  相似文献   

5.
微胶囊核桃粉加工工艺的研究   总被引:5,自引:2,他引:5       下载免费PDF全文
核桃油脂含量在50%~70%,其中90%以上是不饱和脂肪酸,因此被中医学认为有降低胆固醇、防止动脉硬化、补气养血、美容和抗衰老等作用.但是,核桃仁中大量的不饱和脂肪酸极易氧化,使其储存时间有限.本研究采用喷雾干燥微胶囊造粒法对核桃粉的加工工艺进行了研究,利用明胶、大豆分离蛋白、糊精等水溶性壁材包裹核桃仁中的油脂,再经喷雾干燥脱去壁材中的水分使之成为O/W型微胶囊,从而防止油脂与外界氧的接触,得到了油脂含量高达35.3%、包埋率 85.7%、预测保质期12个月的核桃粉产品.  相似文献   

6.
银杏叶提取物微胶囊化研究   总被引:12,自引:4,他引:12  
为使银杏叶提取物能在食品领域得到充分有价值的应用,探索采用微胶囊技术来解决银杏类黄酮难溶于水及强烈苦味的问题。本研究选用阿拉伯胶和β-环状糊精作为银杏黄酮微胶囊壁材,通过喷雾干燥进行微胶囊化。结果表明:选用阿拉伯胶和β-环状糊精(1∶1)作为银杏黄酮的微胶囊壁材,能达到较好的微胶囊化效果,且芯材与壁材的最佳配比为0.1 g/g。最佳喷雾干燥工艺条件为:进料固形物浓度为25%,进风温度为180℃,进料速度为35 mL/min。产品微胶囊化效率达90%以上。  相似文献   

7.
研究目的是以大豆分离蛋白为壁材,对射流空化制备鱼油微胶囊的工艺进行优化。采用喷雾干燥法,研究壁材添加量、乳化剂添加量、芯材添加量及射流空化处理时间对乳液稳定性和鱼油微胶囊包埋率的影响,通过响应面试验分析各因素,得到最优微胶囊制备工艺,并对制备的微胶囊产品同市售产品的结构、理化特性及稳定性进行对比分析。结果表明:在壁材添加量3.21%、乳化剂添加量0.21%、芯材添加量19.70%、射流空化处理时间11.25 min工艺条件下得到的乳液稳定性较好,鱼油微胶囊的包埋率达到94.14%。微胶囊产品微观结构呈球形颗粒,结构致密,颗粒形态完整,粒径小,表面含油率较低,包埋效果好;水分含量为3.07%,溶解度为96.30%,休止角为40.39?,溶解性较好;差示扫描量热分析结果显示,微胶囊热溶解温度较高,可用于常温贮藏。包埋后的鱼油经加速贮藏试验表明微胶囊化可以提高鱼油的氧化稳定性,延长鱼油贮藏期。  相似文献   

8.
喷液包埋技术提高微波泡沫干燥后树莓浆果品质   总被引:2,自引:1,他引:1  
为了在微波泡沫干燥浆果果浆后期喷施大豆分离蛋白和麦芽糊精混合液,使浆果干品表面形成可以降低活性成分降解的包埋层,研究了喷液包埋条件对果浆的干燥特性影响规律,分析了喷液包埋技术对浆果干品中活性成分的保护原因。选择树莓果浆为研究物料,采用微波泡沫干燥工艺,以微波强度、保护液成分质量比和起泡果浆与保护液质量比为影响因素,以物料含水率、干燥温度、活性成分降解率为目标因素,应用电镜对树莓果浆干品微观结构进行观察分析,应用高效液相色谱技术测定干品花青素成分。结果表明浆果微波泡沫干燥中的起泡剂与喷液包埋中保护液成分相近,工艺步骤衔接密切,不影响果浆干燥速度与温度;保护液可使干燥后干品表层形成致密包埋层,有效削弱氧气、光照对活性成分的降解作用,提高矢车菊色素与天竺葵色素2种花青素成分保存量(保存率75%);在微波强度14 W/g,大豆分离蛋白与麦芽糊精质量比3∶7,起泡果浆与保护液质量比4∶1的工艺条件下,可获得花青素和维生素C保留率高的树莓干品(提高20%)。在微波泡沫干燥过程中实施包埋技术可保护干燥后果浆中的活性物质,保证浆果制品营养价值。  相似文献   

9.
喷雾干燥鸡血浆蛋白粉工艺优化   总被引:1,自引:0,他引:1  
为了开发利用鸡血蛋白质资源,该文探讨了鸡血浆蛋白分离及喷雾干燥工艺。首先研究了不同的离心转速和离心时间对鸡血浆蛋白分离效果的影响;使用SD-BASIC喷雾干燥器(英国Labplant公司),研究了喷雾干燥过程热风温度、进料速率对鸡血浆蛋白粉提取率、含水率、粗蛋白质量分数、氮溶解指数、颜色各项指标的影响。结果表明:离心转速和离心时间对血浆蛋白分离效果有显著影响(p<0.05);最佳分离条件为:离心转速3000r/min,离心时间15min。喷雾干燥热风温度、进料速率及两者之间的交互作用对鸡血浆蛋白粉品质均有显著影响(p<0.05);喷雾压力0.3MPa,进料温度为25℃,热风温度150℃、进料速率0.167mL/s时效果最好,此时血浆蛋白粉提取率、含水率、粗蛋白质量分数、氮溶解指数分别为64.289%、4.514%、72.644%、97.295%。研究结果为鸡血浆蛋白粉的工业化生产提供了相关的基础性数据。  相似文献   

10.
为了提高酵素粉中益生菌的存活率以及产品的活性,该研究以植物乳杆菌Lactobacillus plantarum 1-33(Lp 1-33)为发酵菌株,高密度培养后对发酵上清液进行喷雾干燥;通过内源乳化法对菌体进行微胶囊包埋,再对微胶囊进行真空冷冻干燥,最后2部分产物经混匀造粒制得益生菌酵素粉;以包埋率、胃肠道存活率、释放率等为指标,考察多重保护技术对其活性的保护效果。结果表明:采用内源乳化法,乙二胺四乙酸钙为钙载体,质量分数1.5%海藻酸钠为壁材,质量分数0.3%壳聚糖-三聚磷酸钠为涂层材料效果最佳;此条件下制备的微胶囊包埋率≥80%,经模拟胃液处理2 h后其菌体存活率≥50%,模拟肠液处理2 h后释放率≥90%;最佳冷冻保护剂配方为质量分数10%脱脂奶粉、质量分数8%乳糖、质量分数1%抗坏血酸钠、质量分数1%谷氨酸钠,酵素粉与保护剂比例1:10;制备的酵素粉30℃保存3个月,活菌数仍≥9.5lg(CFU/g);与发酵前果汁相比,其清除自由基能力提高了近20%。通过上述多重活性保护技术,提高了菌体的存活率和抗逆境能力,获得高密度、高活性的益生菌酵素粉,为后续产业化的生产提供技术支撑。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

14.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

17.
To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.  相似文献   

18.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

19.
Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.  相似文献   

20.
Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.  相似文献   

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