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1.
An efficient and economical oil expression system that can operate on solar power in rural areas of underdeveloped and developing countries is needed. Recent improvements in both oil extraction and solar energy technologies have indicated the possibilities for fabricating oil extraction equipment. Thus, the objective of our study was to develop a simple oil expression unit capable of producing high quality oil based on solar energy in remote rural areas. A photovoltaic (PV), batch operated, low-pressure oil press, using a 190 W, 12 V dc motor, was designed, fabricated, and tested using coconut and groundnut as the raw material. Samples used in the study were ground to particle size between 500 μm and 2 mm and were pressed at 12 ± 1% moisture content. The press was evaluated based on the oil extraction efficiency (OEE), power consumption, and oil quality. The press had an average OEE of 73% for coconuts and 70% for groundnuts after 12 min of pressing. The oil expression efficiency was characterized by three main stages namely delayed, rapid, and retarded. The power consumption was affected greatly by the pressing time, with power consumption increasing with an increase in the pressing time. The specific energy consumption was found to increase significantly after 8 min of pressing and correlated with the compaction of the cake, which resulted in more power being required to express the entrapped oil. The expressed oil was fresh, free from foots, and of high quality with an average moisture content of 0.015% for coconut oil and 0.019% for groundnut. Analyses showed that the viscosities were 42.1 MPa s (coconut oil) and 59.1 MPa s (groundnut oil), at 25 °C. Overall, the press performed well and was comparable in performance to other types of presses.  相似文献   

2.
This investigation determined the functional properties of protein in Lesquerella fendleri seed and press cake from oil processing. L. fendleri seeds were heat-treated at 82 °C (180 °F) during 120 min residence time in the seed conditioner, and then screw-pressed to extract the oil. Unprocessed ground, defatted lesquerella seeds and press cakes were analyzed for proximate composition and protein functional properties. Protein from unprocessed lesquerella seed showed the greatest solubility (≥60%) at pH 2 and 10 and was least soluble (25%) at pH 5.5–7. Unprocessed lesquerella protein also had high surface hydrophobicity index (So), as well as, excellent foaming capacity and stability, emulsifying properties, and water-holding capacity (WHC) at pH 7. Protein solubility profile of the press cake showed up to 50% reduction in soluble proteins at nearly all pH levels, indicating heat denaturation during cooking and screw-pressing. Foaming capacity of the press cake protein decreased slightly, but foam stability was completely lost. Press cake protein also had markedly reduced values for So, emulsifying properties and WHC, further confirming lesquerella protein’s sensitivity to heat treatment.  相似文献   

3.
4.
In this study, we investigated the possibilities for increasing the valorisation of de-oiled Jatropha press cake (DO-JPC). The studied raw material is the by-product of the alkaline protein extraction of the DO-JPC: NaOH Extracted DO-JPC (NEDO-JPC). Protein solubilisation of NEDO-JPC was performed under neutral and acidic conditions (pH 2, 100 mM maleic acid), at elevated temperature (100, 120, and 140 °C), and at 5% (w/w) dry solids loading. After the treatment, the amount of solubilised protein was determined, as well as the solubilisation of polymeric sugars and formation of sugar degradation products furfural and 5-hydroxymethylfurfural (HMF). Although a clear influence is shown for temperature, no difference in protein solubilisation was found between treatments at pH 7 and pH 2. A maximum of 25% (w/w) of the available protein was solubilised, at 140 °C. The lignocellulose fraction of NEDO-JPC proved relatively recalcitrant to acid hydrolysis, suggesting a more intense treatment to be necessary to sufficiently increase accessibility for cellulolytic enzymes in a lignocellulosic bioethanol process. At €8.00 per tonne DO-JPC, it is concluded that the possibilities for valorisation of the protein fraction of NEDO-JPC at neutral and acid pH are limited, leaving the lignocellulose fraction as a source of valorisation to be investigated.  相似文献   

5.
Sunflower heads are a promising commercial source of low-methoxyl pectin. Although previously reported research was based on a batch extraction process, examples of continuous, countercurrent processes are found with other commodities (beet sugar, vegetable oil). The two types of processes were compared using ground, washed, and dried sunflower heads with 0.75% sodium hexametaphosphate (SHMP) extractant. Under the conditions of pH 2–3.5 at liquid-to-solid (L/S) ratio 32, and L/S ratio 30–45 at pH 3.23, the maximum pectin recovery was similar for the two processes. However, the continuous process maintained maximal recovery over a wide range of pH and L/S ratio. Pectin productivity, which is the rate of pectin extraction per working volume, was much higher in the continuous process than the batch process. At pH 2.5 and L/S ratio 32, it was more than 100% higher. Consequently, the continuous process achieved adequate pectin recovery with less solvent and can be conducted with smaller-size equipment than the batch.  相似文献   

6.
向日葵种子蛋白质的微量提取和双向电泳技术研究   总被引:6,自引:0,他引:6  
从向日葵干种子的中轴(包括胚芽、胚轴及胚根)和子叶的微量样品中提取蛋白质的技术进行了研究,并在此基础上对提取的蛋白质进行了SDS-聚丙烯酰胺凝胶为基础的单向和双向电泳分析,获得清晰的电泳图谱.结果显示:向日葵胚中轴与子叶样品中的蛋白质存在明显差别,而子叶的上部、中部和下部的蛋白质图谱比较相似.通过进一步的双向电泳对比分析可知,胚中轴与子叶的蛋白质相似性系数为0.785,两种组织均具有特异性蛋白质;胚中轴特异蛋白质有18种,子叶特异蛋白质有10种.这些研究结果为进一步的组织特异性蛋白质鉴定及研究子叶和胚中轴的发育机理,以及开展向日葵种子蛋白质组学的研究奠定了实验基础,同时对农业生产中种子纯度鉴定、种子生活力检验及种子发芽实验亦可能具有研究和利用价值.  相似文献   

7.
A partially hydrogenated sunflower oil was compared with a cottonseed-corn oil mixture for frying potato chips. Chips fried in each oil were organoleptically evaluated at two-week intervals during 10 weeks of storage at room temperature. Statistical evaluation of the hedonic ratings of the chips indicated no significant difference in flavor between the chips fried in sunflower oil and those fried in cottonseed-corn oil. Paired comparison testing of chips stored for 2 and 10 weeks indicated no preference for chips fried in the cottonseed-corn oil mixture over those fried in the hydrogenated sunflower oil. The oil content of the chips fried in both oils ranged from 37.6 to 42.9% suggesting an excessive absorption of oil by the chips. The peroxide values of the oils extracted from the potato chips indicate a trend toward greater autoxidation of the cottonseed-corn oil mixture compared to the sunflower oil. During storage, changes in the fatty acid composition of oils extracted from potato chips were minor. Chemical evaluation of oil samples taken during frying runs showed that both oils were of good quality after 23 hours of frying chips.  相似文献   

8.
The objective of this study was to optimize the mechanical oil extraction of Jatropha curcas seeds by increasing the efficiency of oil recovery and decreasing oil residues in press cake. The experiments were carried out with mechanical screw press type - Komet D85-1G. Four setups were created by parameter combination of two different screws (16 and 21.5 mm choke ring size), with two different press cylinders (1 and 1.5 mm bore size), three different nozzles (8, 10 and 12 mm nozzle diameter) and three rotational speeds (low, medium and high). Oil recovery reduced when rotational speed increases for all setups; highest oil was 89.4% (m/m). The oil recovery was increasing when energy input increased and decreasing when seed material throughput increased. The relations between energy input and seed material throughput followed a strict pattern, which correlated with oil recovery. This correlation can be used for determining the optimal operation parameters.  相似文献   

9.
不同生态型复播油葵生育规律的研究   总被引:2,自引:1,他引:2  
按生育期的不同将新疆北疆沿天山一带复种油葵品种分为3种生态型,分析其生育特性,结果表明:晚熟型品种在叶片生长特点、群体冠层结构及同化物运动等方面均优于早熟型及中熟型品种,但由于在灌浆中后期气温过低,造成灌浆不充分,制约其高产潜力的发挥,从而表现为低产。故鉴于当地气候条件,复播油葵应选用早熟型品种,但需采取相应的栽培措施,以利于建立合理的群体结构及提高籽粒充实程度。  相似文献   

10.
The leaves (needles) of eastern red cedar (Juniperus virginiana L.) contain two important natural products: essential oil and podophyllotoxin. The hypothesis of this study was that it may be possible to extract both essential oil and podophyllotoxin from the leaves of the tree, by using a dual extraction method. Podophyllotoxin was obtained from the leaves following steam distillation of the leaves to produce the essential oil, indicating that steam distillation did not degrade podophyllotoxin. Furthermore, a product with 6% purity podophyllotoxin was obtained from the steam-distilled plant material, demonstrating the possibility for the establishment of an industrially economic protocol for dual extraction of these two natural products. Our study demonstrated that J. virginiana leaves, currently a waste-product from the timber industry, could be sequentially extracted for essential oil and podophyllotoxin and utilized as a by-product instead. We also found that the J. virginiana heartwood (a traditional source for cedarwood essential oil) does not contain podophyllotoxin. This is the first study to report both podophyllotoxin and essential oil in J. virginiana, and the first report on the dual extraction of these two natural products from the same biomass samples.  相似文献   

11.
The optimal process conditions for solvent-free microwave extraction(SFME) of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodology(RSM). A Box-Behnken design(BBD) was applied to evaluate the effects of three independent variables: moisture content(A: 54%–74%), microwave power(B: 300–500 W) and microwave time(C: 20–40 min), on the extraction yield of essential oil. The compounds of the essential oils obtained...  相似文献   

12.
In previous aqueous enzymatic oil extraction (AEOE) experiments we reported a best free oil yield of 49% of the hexane extracted yield of dry fractionated corn germ. In the current experiments, a dispersion of 10% cooked, dry-fractionated germ in water was treated with α-amylase, glucoamylase and a cellulase complex. Free oil was collected by centrifuging a foam fraction of the dispersion. Several dispersion treatments were tried to evaluate their release of free oil and effect on the production of foam. The foam contained up to 8% free oil (dispersed from germ containing 26% oil) and fines oil (not centrifugally separable), protein and germ particles. Treatment with α-amylase and glucoamylase prior to treatment with the commercial cellulase used in previous AEOE studies increased the free oil yields about 25-61% of the hexane-extractable yield. A preliminary cost analysis indicates that oil separation with the amylase enhanced AEOE appears to be preferable to AEOE alone and profitable if crude corn oil cost exceeds $1.1/kg ($0.50/lb).  相似文献   

13.
Durable press finish of cotton fabric using malic acid as a crosslinker   总被引:1,自引:0,他引:1  
It has been considered that malic acid,α-hydroxy succinic acid, could not form crosslinks in the cellulosic materials unless activated by other polycarboxylic acids such as butanetetracarboxylic acid or citric acid because there are only two carboxylic acids per molecule available for the formation of one anhydride intermediate. However we found that the dicarboxylic malic acid with sodium hypophosphite catalyst without the addition of other crosslinkers was able to improve wrinkle resistance of cotton up to 294° (dry WRA) and 285° (wet WRA), which is a measure of crosslinking level in cotton.1H FT-NMR, FT-IR and GPC analysis indicated the in-situ formation of an trimericα, β-malic acid with a composition of 1:3 through the esterification between hydroxyl group and one of carboxylic groups in malic acid during curing. The crosslinking of cotton was attributed to the trimericα, β-malic acid, a tetracarboxylic acid, which can form two anhydride rings during curing. The influence of crosslinking conditions such as concentrations of malic acid and catalyst, pH of the formulation bath, and curing temperature were investigated in terms of imparted wrinkle resistance and whiteness. The addition of reactive polyurethane resin in the formulation slightly increased the mechanical strength retention of crosslinked fabric coupled with additional increase in wrinkle resistance.  相似文献   

14.
葵花子油不同提取工艺的比较   总被引:2,自引:0,他引:2  
通过比较超临界CO3提取葵花子油的均匀设计实验和微波、超声波诱导提取葵花子油的正交实验结果,考察影响提取的主要因素,寻求最佳萃取工艺.超临界CO2萃取最佳工艺条件为:压力32MPa,温度32℃,CO2流量25kg/h,萃取时间80min,得率36.45%;微波萃取最佳工艺条件为:溶剂为正己烷,物料质量与溶剂质量比例1:3,辐射时间7min,辐射功率720w,得率27.12%.超声波萃取最佳工艺条件为:物料质量与溶剂质量比例1:7,溶剂为正己烷,浸泡时间18h,得率17.37%.结果表明超临界CO3萃取葵花子油品质最好,而且萃取也最高,质量最稳定.  相似文献   

15.
The physicochemical properties, fatty acids profile and triglyceride compositions of the stillingia oil were analyzed. The stillingia oil was found to contain 98.79% neutral lipids, 0.22% phospholipids and 0.99% glycolipids, which exhibited varying contents of fatty acids. The major triglyceride was double linoleic acid linolenic acid triglyceride, which accounted for approximately 79.49% of the total triglycerides. Preparation of biodiesel from stillingia oil was investigated by enzyme transesterification with methanol as the acyl acceptor. The results showed that lipase type (Novozym 435, Lipozyme TLIM and Lipozyme RMIM), reaction systems (in solvent-free and tert-butanol system) and operational parameters (lipase loading, reaction time, temperature, and molar ratio of alcohol to oil) influenced the biodiesel yield. Fuel properties of biodiesel from stillingia oil were evaluated and all were in acceptable range for use as biodiesel in diesel engines, and had remarkable flash point and satisfactory cold flow properties. It was concluded that stillingia oil was an alternative potential feedstock oil for biodiesel production.  相似文献   

16.
The potential use of quality protein transgenic maize (genetically modified maize with the cDNA of amarantin) for preparation of flour and tortillas through an extrusion lime cooking process was investigated. Tortillas from extruded transgenic maize flour had similar physicochemical and sensory properties than those from the commercial brand MASECA™; however, the former had the highest (P < 0.05) protein content (12.91 vs 8.93%, db), essential amino acids content, calculated protein efficiency ratio (C-PER; 2.27 vs 0.90) and protein digestibility corrected amino acid score (PDCAAS; 55.54 vs 30.18%) and therefore they were nutritionally better. The use of transgenic maize for flour and tortilla preparation through an extrusion lime cooking process may have a positive impact on the nutritional status of people from countries where maize is the basic staple food. It also represents an alternative process to nixtamalization that requires little energy and water, it does not generate wastewater, and all components of the maize kernel are retained.  相似文献   

17.
In order to further exploit the by-products of Isatis indigotica Fort., the seed oil was studied for its extraction and physicochemical properties. Ultrasound-assisted extraction (UAE) was used, and the parameters affecting seed oil recovery were optimized through response surface methodology (RSM). The optimum conditions were as follows: solvent-to-sample, 24:1; particle size, 110 meshes; extraction temperature, 49 °C; and extraction time, 44 min. Which resulted in a maximum oil recovery of 81.20 ± 0.21% (n = 3). Furthermore, the effects of UAE on the yield, fatty acid compositions, physicochemical properties, and microstructure of the seed powder were also investigated by calculating the recovery rate, utilizing a gas chromatograph fitted with a mass spectrometer (GC-MS), and performing scanning electron microscopy, respectively. The results show that UAE was an effective method for the seed oil extraction and the high content of unsaturated fatty acids (93.81%) demonstrates the oil has potential benefits for the cosmetics, edible products, or pharmaceutical industries.  相似文献   

18.
The effects of three independent variables: solvent polarity, temperature and extraction time on the antioxidant capacity, total phenolic content and phenolic acid composition in extracts obtained from sunflower shells before and after enzymatic treatment were studied. Response surface methodology based on three-level, three-variable Box-Behnken design was used for optimization of extraction parameters and evaluation of their effect on antioxidant capacity and total phenolic content in shell extracts.The average antioxidant capacities of extracts from sunflower shells without enzymatic treatment (368.1-1574.4 μmol TE/100 g) were higher than those for cellulolytic and pectolytic enzymes-treated shells (222.7-1419.0 and 270.7-1570.7 μmol TE/100 g, respectively). The content of total phenolic compounds ranged between 58.2-341.2 mg CGA/100 g, 26.7-277.3 mg CGA/100 g and 51.4-301.5 mg CGA/100 g for extracts obtained from shells without enzyme and treated with cellulolytic and pectolytic enzymes, respectively. Total phenolic content (TPC) in the studied shell extracts correlated significantly (p < 0.0001) positively with their antioxidant capacity determined by the ferric reducing antioxidant power (FRAP) method (r = 0.9275). Results of FRAP, TPC and phenolic acid composition in the studied shell extracts depend on the extraction conditions (solvent polarity, temperature, time), but they are independent on the addition of enzyme solutions. The antioxidant capacity and total phenolic content in the resulting extracts increased with a line in extraction temperature and solvent polarity.  相似文献   

19.
高产高油抗病油葵杂交种晋葵5号的选育   总被引:4,自引:0,他引:4  
晋葵5号是以雄性不育系76202-3A为母本,恢复系902-11R为父本组配选育而成,该杂交种抗旱、耐盐碱、耐瘠薄、耐菌核病能力强,含油率达51.44%,品种鉴定平均产量3823.5kg/hm^2,比对照品种汾葵杂3号增产13.9%,生产示范平均产量2056.5kg/hm^2,比对照品种晋葵2号增产17.0%,适宜高寒山区春播及麦茬复播。  相似文献   

20.
为鉴定评价我国向日葵(Helianthus annuus L.)种质资源在南方地区的表现,筛选构建向日葵核心种质,以422份向日葵种质为材料,在进行2年鉴定观察的基础上,采用描述性统计、相关性分析、主成分分析等方法对11个表型农艺性状进行分析评价。结果表明,原始群体的这些农艺性状具有较大的变异幅度,其变异系数(CV)为3.60%~83.32%,平均变异系数为20.93%,其中分枝株率(0%~62.5%)、单株粒重(9.70~232.35 g)、百粒重(4.60~14.92 g)、叶片数(14.40~48.38个)和株高(103.75~260.00 cm)变异幅度较大;性状间表现出显著的相关性,主成分分析表明,影响性状的4个主要成分解释了总方差的71.72%。采用QGAstation 2.0软件构建了72组核心种质候选群体,并根据均值差异百分数(MD)、方差差异百分率(VD),极差符合率(CR)和变异系数百分率(VR),获得组获得1组包含84份材料的最佳核心种质群体。聚类分析将84份核心资源分为5大类,与原群体相比,所选核心种质均值无显著差异,方差显著提高,能最大限度代表原始油葵种质资源保存和利用。  相似文献   

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