首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
采用气相色谱法和高效液相色谱法研究了福鼎大白茶、福云6号、黄棪和肉桂4个品种茶籽成熟过程中油脂含量、脂肪酸组成、维生素E和角鲨烯含量等主要功能性成分的变化规律。结果表明,随着茶籽成熟程度提高,其中的主要营养物质持续积累,含水率呈下降趋势;茶籽的含油率呈现持续增长的趋势,在成熟前期含油率上升较快,后期趋缓并达到最高值,4个品种茶籽的平均含油率为24.24%;维生素E含量均出现"双波峰"增长趋势,并在后期快速增加至最大值,其中福云6号的维生素E含量最高达到1 060.29μg/g;角鲨烯含量呈现成熟前期增加、后期降低的趋势,其中肉桂的角鲨烯含量为161.42μg/g。在茶籽成熟过程中,棕榈酸的相对质量分数呈现缓慢降低的趋势,而硬脂酸的相对质量分数则呈现缓慢增加的趋势;油酸的相对质量分数总体呈现先增加、再降低、然后持续增加的趋势,福鼎大白茶、福云6号、肉桂和黄棪成熟茶籽的油脂中油酸相对质量分数分别为50.43%、45.98%、52.62%和52.98%;亚油酸的相对质量分数整体呈现成熟前期降低、中期增加、后期再降低的趋势,福云6号、福鼎大白茶、肉桂和黄棪成熟茶籽的油脂中亚油酸相对质量分数分别为31.65%、27.36%、24.66%和24.07%。  相似文献   

2.
Sesame seeds were boiled and allowed to sprout under ambient condition (30±2 °C) with an objective to reduce or eliminate the bitter taste associated with them. The untreated seeds were used as a control. The proximate composition, functional and organoleptic properties of defatted sesame flour were assessed at room temperature. There was a slight increase (about 10%) in protein content of sprouted seeds. The foaming capacity of flours from untreated, sprouted and boiled seeds were 34.6, 38.5 and 11.5%, respectively. The flour from the boiled seeds had the highest foam stability. Flours from untreated or sprouted seeds, gelation started at the least concentration of 6% whereas that from boiled seed was 11%. The emulsion capacity of flours from the untreated or sprouted seeds was the same (27.6 g oil/g sample) while that from boiled seeds was 12.9 g oil/g sample. Emulsion stability with prolonged storage appeared to be more with flours from the sprouted or boiled seeds than that from the untreated ones. The water absorption properties of flours from the untreated, sprouted and boiled seeds were 8.0, 5.9 and 6.5 g H2O/g sample, respectively whereas the oil absorption capacity same (5.9 g oil/g sample). The bitter taste in flours from the untreated or sprouted was high. The bitter taste was not detected in flour from boiled seeds and the functional properties of the flour were not deleteriously affected except foaming and emulsion capacity. Therefore, this boiling method of debittering sesame seed could be practised. The quality of sesame flour obtained with this boiling method could still serve its role in traditional dishes and in the formulation of some other conventional food products.  相似文献   

3.
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   

4.
Chia (Salvia hispanica L.), an annual herb of the Labiatae family, produces seeds which were one of the basic foods of Central American civilizations in pre-Columbian times. Chia seed contains the highest known percentage of α-linolenic fatty acid of any plant source. In recent years, chia seed has become increasingly important for human health and nutrition because of its high content of α-linolenic fatty acid, and the beneficial health effects that arise from its consumption. A study was undertaken to characterize protein and oil contents as well as fatty acid composition of chia seeds grown in some larger commercial fields, in an attempt to determine how these components are affected by location. Oil saturation tended to decrease as elevation of seed production increased, with decreasing levels of palmitic, stearic, oleic, and linoleic fatty acids found. The main constituent in the chia oil was ω-3 α-linolenic fatty acid, and ranged from 64.8% to 56.9%. Differences were significant (P < 0.05) among locations. Significant differences in protein content and fatty acid composition were also found for the commercially grown chia originating from three ecosystems. It is possible that these differences could be used to distinguish chia's origin, if additional research was undertaken to characterize such differences.  相似文献   

5.
With the use of GC–MS, the resolution and identification of alkaloids occurring in the seeds of six species of wild Mexican lupins has been achieved. From among 46 detected compounds it was possible to identify unambiguously 24 of them. Most of identified alkaloids are from the lupanine group. The percentage content of particular alkaloids in comparison with the total alkaloid pool (ranged from 2.0 to 3.5%) in the species tested has also been determined. Alcoholic extract from Lupinus exaltatus seeds (ALP) with low RFOs and sucrose content, introduced in different doses (80, 320 and 1600 mg d.w./pot.) to soil has increased paprika fruit yield (for doses 320 and 1600 mg/pot) and its vegetative mass (for all applied doses). The experiments were carried out in greenhouse in controlled conditions within a period of March–December 2001.  相似文献   

6.
大豆种子脂肪和蛋白质积累规律的研究   总被引:30,自引:5,他引:30  
张恒善  付艳华 《大豆科学》1993,12(4):296-301
用8-10个公演成分不同的大豆品种为试材,研究了大豆“蛋脂”形成及积累规律。在种子形成的过程中,干重的积累是递增的曲线。中早熟品种脂肪相对含量在开花后16-26天迅速增加,脂肪形成高峰在开花后36-46天。以后多数品种略有下降,或降后稍有回升,少数品种在个别年份一直缓升。蛋白质含量呈现前高,中降或降后稍有回升趋势,少数品种在个别年份稳定上升或缓降。脂肪含量初期高,成熟时亦高,蛋白质含量变化亦如此。  相似文献   

7.
Milkweed is now being grown commercially mainly for the production of floss used as hypoallergenic fillers in pillows and comforters. More recently, the use of milkweed seed oil in soaps and personal care products is being explored. The oil used in this effort was obtained by screw pressing whole milkweed seeds. The milkweed seed has a considerable amount of paper-thin wing around the edge of the hull. The light wing contributes greatly to the low bulk density of the seeds and the efficiency of oil extraction. This study explored the feasibility of removing the wings from the seeds to reduce the amount of material going into oil extraction. Hand-fractionation of the seeds showed that the wings, hulls, and kernel accounted for 12.2%, 51.2%, and 36.5% of the seed weight, respectively. The wing contained 1% of the total oil. Most of the oil is in the kernel (73%), but a significant amount is also found in the hulls (22.4%). Mechanical removal of seed wing was evaluated using an impact huller. Seeds (1 kg) with 4%, 7.2%, and 10% moisture were passed through the huller running at 1250 and 1750 rpm impeller speeds. The seeds discharged from the huller were screened to separate the intact seeds and partially dewinged seeds, dewinged seeds, and fines. Seed wings were effectively removed at seed moisture contents and impeller speed combinations of 7% and 1250 rpm or 10% and 1700 rpm. This was verified using 100 kg seeds. Removing the wings reduced the weight of the seeds by 13%, reduced the volume by 46%, and increased the bulk density by 63% while losing less than 5% of the total oil. The oil content of the dewinged seeds was 16.6% higher than the whole seeds. These reductions in seed weight and volume can significantly increase the output of the oil extraction equipment.  相似文献   

8.
The chemical composition of seeds can vary enormously with respect to the major constituents, oil, carbohydrate and protein. Thus oil can vary from about 2% to 70%, carbohydrate from 5% to 80% and protein from 3% to 50% in different seeds. During evolution the pathways of seed metabolism in different crops have taken diverse routes all of which are compatible with seed function. Nevertheless, these differences have important inferences for the dietary value of a particular crop. The breeder in striving to increase yields has furthermore selected for biochemical and physiological characteristics which can lead to constraints to further improvements as expressed for example in the negative correlations between yield and protein content and between yield and protein quality. This paper examines the biochemical pathways involved in seed metabolism and calculates the efficiency of utilisation of input materials both with respect to the total and the ‘useful’ components of the grain using stoichiometric considerations. Constraints due to controlling reactions in biochemical pathways, those due to inefficient biochemical synthetic routes and limitations due to inputs into the seed, will be analysed. Kinetic as well as thermodynamic constraints will be considered such as those due to varying ammounts, activities or locations of enzymes. Particular emphasis will be placed on protein metabolism.  相似文献   

9.
Meta-analysis of environmental effects on soybean seed composition   总被引:1,自引:0,他引:1  
The value of commodity soybean depends on the concentration of protein and oil in the seeds. While seed composition is primarily genetically determined, environmental conditions during seed development also affect seed component accumulation, and can result in protein and/or oil deficits for processing. To understand the general environmental effects on soybean composition, we conducted a meta-analysis of published data quantifying the effect of water stress, temperature, and/or nitrogen supply on seed protein and oil accumulation and their final concentrations. The meta-analysis showed that water stress reduced the content (mg per seed) of protein, oil and residual seed fractions. Protein accumulation, however, was less affected than were oil and residual accumulation, resulting in an increase in final protein concentration (% dry weight). Growth at high temperature also increased protein concentration in a manner similar to that observed for water stress. But in neither case was the increase in protein concentration due to an increase in protein synthesis per se. Increasing nitrogen supply to seeds cultured in vitro and to plants grown hydroponically increased both final seed protein concentration and content. But the magnitude of seed component response to experimental manipulation under field conditions was far less than that observed in the Uniform Soybean Regional Field Tests. Greater knowledge of the physiological processes that regulate these responses is essential to predict when and where future protein deficits might occur. Limitations of the meta-analysis approach and implications for future research on soybean seed composition are discussed.  相似文献   

10.
高空气球飞行对鸡冠花籽粒产量及籽油脂肪酸组分的影响   总被引:3,自引:0,他引:3  
利用高空气球搭载了2个品种鸡冠花(CelosiacristataL.)的种子,进行空间诱变处理。飞行高度为40112km,飞行时间近3h54min,回收后播种栽培,采收子一代(SP1)种子,对其千粒重、单株籽粒重、籽油含量和脂肪酸组分进行测定分析,并与地面对照组进行比较。试验结果表明,SP1代种子千粒重、单株籽粒重、分枝穗数均比对照明显增加。2个品种SP1代籽油含量分别比对照提高6.3%、5.1%。籽油中脂肪酸组分无明显变化。但是,主要脂肪酸含量与对照组相比发生显著差异。例如,黄色普通鸡冠籽油中MUFA含量比对照增加38.7%,PUFA则降低8.7%。高空诱变对不同基因型品种的鸡冠花籽油脂肪酸合成产生了不同的效应。   相似文献   

11.
Moringa oleifera Lam. is a member of Moringaceae family which grows throughout most of the tropics, and is native to sub-Himalayan tracts of north west India, Pakistan, Bangladesh and Afghanistan. Moringa seed concentrates 35-45% oil which is considered a great natural cosmetic emollient almost total natural absence of color and odor, and high oleic acid concentration (>73%). To assess their production potential in the Arid Chaco, The Yungas Tropical Forest, Tropical Lowland Forest, and in the Sub-Humid Chaco Ecosystems of South America, a comparative trial was undertaken to determine their seed yield and oil content. Arid Chaco Ecosystem: significant (P < 0.05) difference in seed yields among years were found, with 176.17 and 481.25 kg/tree recorded for 1- and 2-year-old trees, respectively. Sub-Humid Chaco Ecosystems: the difference in seed yield and oil percentage between years was significant (P < 0.05). Comparison between years showed significantly (P < 0.05) higher seed yields, and significantly (P < 0.05) lower oil percentage for the two years old trees, than for the one year old trees. The oil/tree content was significantly (P < 0.05) higher for two years old trees than for one-year-old trees. Yungas Tropical Forest Ecosystem: seed oil percentage was significant (P < 0.05) higher in one-year-old trees than in seeds of two years old trees. Overall: over the tree years, oil percentage was significantly (P < 0.05) higher for seeds produced at the Arid Chaco than at the Sub-Humid Chaco. The seed/tree yields and the oil/tree content were no significantly (P < 0.05) different among the three ecosystems. However, when oil percentage per tree and seed yield/tree were combined trees from Sub-Humid Chaco and from Yungas Tropical Forest yielded significantly (P < 0.05) higher oil content compared to that from Arid Chaco trees.  相似文献   

12.
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   

13.
This study determined the effects of oil processing conditions on functional properties of milkweed seed proteins to evaluate their potential for value-added uses. Flaked milkweed seeds were cooked at 82 °C (180 °F) for 30, 60 or 90 min in the seed conditioner, and then screw-pressed to extract the oil. Proximate composition and protein functional properties of cooked flakes and press cakes were determined and compared with those of unprocessed ground, defatted milkweed seeds. Milkweed seed protein was most soluble at the pH range of 7–10, had excellent emulsifying properties, and produced substantial but highly unstable foams. Heat applied during seed cooking and screw-pressing did not reduce protein solubility and improved emulsifying, foaming, and water-holding capacities. Emulsifying capacity was much higher at pH 10 than at pH 7. These results showed that the protein in both the milkweed seed and its press cake from oil processing has useful functional properties that could be utilized in applications such as paint emulsifier and adhesive extender.  相似文献   

14.
Pennycress is currently being developed as an oilseed crop for biofuel production. Pennycress seeds harvested from a field near Peoria, Illinois, provided our first opportunity to conduct an oil extraction study on a pilot scale. The goals of this study were to determine the effects of seed moisture and cooking on the pressing characteristics of pennycress seeds and to evaluate the quality of the oils extracted. Pennycress seeds (60 kg) with 9.5 and 16% moisture contents (MC) were cooked and dried (82–104 °C) using a steam-heated 3-deck laboratory seed cooker. The residence times were varied to produce cooked seeds with MCs ranging from 1.0 to 13.0%. The cooked seeds were pressed immediately using a heavy duty laboratory screw press. Pressing rate, press load, and residual oil in the press cakes were determined. The oils extracted were analyzed for solids content (foots), free fatty acid (FFA) content, color, and phosphorus (P), calcium (Ca), magnesium (Mg), and sulfur (S) contents. Pressing uncooked pennycress seeds with 9.5% MC produced press cake with 10.7% oil (db), extracting 75.1% of the oil in the seed. Cooking and drying the seeds between 3 and 4% MC provided the highest oil recovery at 86.3 and 88.0% for seeds with 9.5 and 16% starting seed MC, respectively. The pressing rates and press loads at these MCs were similar. Compared to the oil from uncooked seeds, the oils from cooked seeds had higher foots (1.55–1.73% vs. 0.52%), slightly higher FFA contents (0.40–0.46% vs. 0.30%), and slightly higher red values in AOCS RY color scale (4.1R–6.2R vs. 2.4R). Cooking increased the phosphatide content but the amount was still comparable to degummed oils. The sulfur levels in the expelled oil were higher than the amounts found in rapeseed oil and varied considerably depending on the seed moisture and the extent of cooking employed.  相似文献   

15.
在春油菜开花期间,开花后第一天的日平均温度是影响结籽率的主要因素,其它日期的日平均温度以及日最高温度、日最低温度对结籽率的影响较小。春油菜主序的结籽率、每角饱粒数、总胚珠数极显著高于分枝。  相似文献   

16.
The oil extraction of Jatropha curcas created the large amount of the by-product from its seeds. An application of solid-state fermentation (SSF) was considered to be of value to these raw materials. This study investigated the potential of a utilization of deoiled J. curcas seed cake as substrate for protease productions by Aspergillus oryzae. While various parameters for SSF was conventionally individually optimized, five parameters were simultaneously examined based on Taguchi method. The effect of three different levels of five factors, including moisture content of substrate, inoculums size, incubation temperature, type of porous substrate and incubation time were examined. The optimum conditions for the protease production by A. oryzae obtained from this experiment were 45% moisture content of substrate, 10% inoculums size, 30 °C incubation temperature, deoiled J. curcas seed cake mixed with cassava bagasse ratio 4:1 as porous substrate at 84 h of incubation time. By adjusting the conditions to these optimum levels, the protease production increased up to 4.6 times as many as the protease yield from the non-optimizing experiment. The use of statistical approach, Taguchi method, provided a satisfactory outcome in defining the optimum conditions for protease production by A. oryzae. Further, the utilization of deoiled J. curcas seed cake as substrate for SSF was proven as the suitable practice for this agricultural waste, in order to develop for an industrial use.  相似文献   

17.
一种高利用价值油料作物—亚麻荠的研究进展   总被引:2,自引:0,他引:2  
本文在对亚麻荠的栽培和育种现状进行阐述的基础上,重点概括了其种子中两种主要化学成分油脂和蛋白,具体包括油脂含量和脂肪酸组成、脂质活性成分及降血脂作用、油脂在生物能源上的应用,蛋白含量和氨基酸组成、蛋白饼粕加工利用等方面的研究状况。最后分析了约束亚麻荠发展的因素,并提出了相应的建议。  相似文献   

18.
不同生态区域环境对中国大豆品质的影响   总被引:16,自引:11,他引:16  
本文研究结果表明,大豆蛋白质及脂肪含量高低,除受品种本身内在遗传基因控制外,还受生态区域环境因素(如地理纬度、海拔高度等)的影响。凡是环境条件有利于蛋白质形成,籽粒蛋白质含量高时,脂肪含量则相应减少;反之,环境条件有利于脂肪形成,脂肪含量增加时,蛋白质含量相应减少。 根据研究结果,初步将中国大豆品质生态区域划分为五大区,即:1.东北大豆生态区;2.黄淮海流域大豆生态区;3.长江流域大豆生态区;4.南方秋、春大豆生态区;5.西北干旱大豆生态区。  相似文献   

19.
The aim of this study was to reduce the breakdown of hybrid vigour by crossing maize × teosinte subspecies through induced tetraploidy and to improve the biomass and reproductive fertility of the induced tetraploids. To achieve this, seeds of maize breeding lines selected from an open‐pollinated population ‘Sargodha‐2002’ and a maize × teosinte cross were germinated in colchicine solution (0·25, 0·5 or 1·0%) until they had a thick radical and protruded plumule. Colchicine at 0·5% induced the highest number of tetraploids with the lowest number of chimeric plants. The induced tetraploids of maize and maize × teosinte crosses showed a significant ( 0·05) increase in leaf area (5 and 14%), total soluble solids (20 and 18%), leaf oil percentage (42 and 12%) and leaf crude protein contents (10 and 14%) in leaves relative to the diploid subspecies. Moreover, induced tetraploidy also arrested hybrid vigour by slowing down the decay of heterosis in progenies (4x) for plant height, leaf biomass and leaf oil percentage. Induced maize × teosinte hybrid tetraploids selected for frequent bivalent chromosome pairing resulted in higher seed setting cob?1 (increased 58%), pollen fertility (increased 59%) and seed setting percentage (increased 100%) than the quadrivalent variant.  相似文献   

20.
Defatted tomato seed cake was analysed for its nutrient composition and its protein quality was evaluated in 21 day old male rats. The cake is found to be rich not only in protein (40%), minerals like phosphorus, calcium and magnesium but also in crude fiber. Lysine content of the cake protein was in the range of that found in groundnut cake protein. Sulphur containing amino acids were limiting in this protein. However, the protein quality of the cake, as judged by PER and NPU, was relatively lower compared to that of groundnut cake. Its high lysine content (5.1g%) will be of help to improve the cereal based farm animal feed quality.  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