Characterization and quantification of proteins in lecithins

Several methods for extraction and quantification of proteins from lecithins were compared. Extraction with hexane-2-propanol-water followed by amino acid analysis is the most suitable method for isolation and quantification of proteins from lecithins. The detection limit of the method is 15 mg protein/kg lecithin, and the quantification limit is 50 mg protein/kg. The relative repeatability limits for samples containing 0-500 and 500-5000 mg protein/kg sample were 12.6 and 7.5%, respectively. The protein recovery ranged between 101 and 123%. The protein content has been determined in different kinds of lecithins. The results were as follows: standard soy lecithins (between 232 and 1338 mg/kg), deoiled soy lecithin (342 mg/kg), phosphatydylcholine-enriched soy lecithins (not detectable and 163 mg/kg), sunflower lecithins (892 and 414 mg/kg), and egg lecithin (50 mg/kg). The sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein patterns of the standard soy and sunflower lecithins are very similar to those of soy flour. The protein profile of the egg lecithin shows several bands with a broad range of molecular masses. The molecular masses of the main proteins of soy lecithins and soy flour have been determined by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and ranged from 10.5 to 52.2 kDa. Most of the major proteins from soy and sunflower lecithins identified by MALDI-MS and electrospray tandem MS belong to the 11S globulin fraction, which is one of the main fractions of soy and sunflower seeds. In addition, the seed maturation protein P34 from the 7S globulin fraction of soy proteins has also been identified in soy lecithins. This protein has been reported as the most allergenic protein in soybean.     

Effect of inoculum,variety, nitrogen,phosphorus, and potassium on yield,protein and oil content of soybeans at jabalpur,M.P. India

Abstract

Regardless of inoculum or fertility rate Bragg outyielded Clark 63 soybeans. Yields of Bragg and Clark 63 were increased about 1000 kg per ha by treatment with inoculum at the rate of approximately 313, 000 bacteria per seed. At the highest rate of applied N, yields of uninoculated soybeans, were lower than the inoculated soybeans at the lowest applied N rate. Phosphorus fertilizer increased yields at a decreasing rate and yields were decreased at the highest rate of applied P. Potassium fertilizer had a negative effect on soybean yields and did not significantly effect the protein or oil content of soybean seed. With increasing P fertilizer rates, there was a decrease in oil content and in increase in protein content of soybean seed.     

Biofortification of soybean meal: immunological properties of the 27 kDa γ-zein

Legumes, including soybeans ( Glycine max ), are deficient in sulfur-containing amino acids, which are required for the optimal growth of monogastric animals. This deficiency can be overcome by expressing heterologous proteins rich in sulfur-containing amino acids in soybean seeds. A maize 27 kDa γ-zein, a cysteine-rich protein, has been successfully expressed in several crops including soybean, barley, and alfalfa with the intent to biofortify these crops for animal feed. Previous work has shown that the maize 27 kDa zein can withstand digestion by pepsin and elicit an immunogenic response in young pigs. By use of sera from patients who tested positive by ImmunoCAP assay for elevated IgE to maize proteins, specific IgE binding to the 27 kDa γ-zein is demonstrated. Bioinformatic analysis using the full-length and 80 amino acid sliding window FASTA searches identified significant sequence homology of the 27 kDa γ-zein with several known allergens. Immunoblot analysis using human serum that cross-reacts with maize seed proteins also revealed specific IgE-binding to the 27 kDa γ-zein in soybean seed protein extracts containing the 27 kDa zein. This study demonstrates for the first time the allergenicity potential of the 27 kDa γ-zein and the potential that this protein has to limit livestock performance when used in soybeans that serve as a biofortified feed supplement.     

Accumulation of genistein and daidzein, soybean isoflavones implicated in promoting human health, is significantly elevated by irrigation

To circumvent drought conditions persisting during seed fill in the mid-south U.S. soybean production region, researchers have developed the early soybean (Glycine max [L.] Merr.) production system (ESPS), which entails early planting of short-season varieties. Because soybean supplies a preponderance of the world's protein and oil and consumption of soy-based foods has been associated with multiple health benefits, the effects of this agronomic practice on seed quality traits such as protein, oil, and isoflavones should be investigated. Four cultivars of soybean, two from maturity group IV and two from maturity group V, were planted in April (ESPS) and May (traditional) in a two-year study at Stoneville, MS. Near-infrared analysis of soybean seed was utilized to determine the percentages of protein and oil. Dependent upon variety, the oil content of the early-planted crop was increased by 3-8%, whereas protein was not significantly changed. Visualization of protein extracts fractionated by sodium dodecyl sulfate-polyacrylamide electrophoresis and fluorescence two-dimensional difference gel electrophoresis revealed that early planting did not affect the relative accumulation of the major seed-storage proteins; thus, protein composition was equal to that of traditionally cultivated soybeans. Maturity group IV cultivars contained a higher percentage of oil and a lower percentage of protein than did the maturity group V cultivars, regardless of planting date. Gas chromatographic separation of fatty acids revealed that the percentages of saturated and unsaturated fatty acids were not significantly altered by planting date. Methanol extracts of seed harvested from different planting dates when analyzed by high-performance liquid chromatography showed striking differences in isoflavone content. Dependent upon the variety, total isoflavone content was increased as much as 1.3-fold in early-planted soybeans. Irrigation enhanced the isoflavone content of both early- and late-planted soybeans as much as 2.5-fold. Accumulation of individual isoflavones, daidzein and genistein, was also elevated by irrigation. Because this cultural practice improves the quality traits of seeds, ESPS provides an opportunity for enhancing the quality of soybean.     

Extraction and characterization of oil bodies from soy beans: a natural source of pre-emulsified soybean oil

Soybeans contain oil bodies that are coated by a layer of oleosin proteins. In nature, this protein coating protects the oil bodies from environmental stresses and may be utilized by food manufacturers for the same purpose. In this study, oil bodies were extracted from soybean using an aqueous extraction method that involved blending, dispersion (pH 8.6), filtration, and centrifugation steps. The influence of NaCl (0-250 mM), thermal processing (30-90 degrees C, 20 min) and pH (2-8) on the properties and stability of the oil bodies was analyzed using zeta-potential, particle size, and creaming stability measurements. The extracted oil bodies were relatively small ( d 32 approximately 250 nm), and their zeta-potential went from around +12 mV to -20 mV as the pH was increased from 2 to 8, with an isoelectric point around pH 4. The oil bodies were stable to aggregation and creaming at low (pH = 2) and high (pH >/= 6) pH values but were unstable at intermediate values (3 相似文献   

Stepwise extraction of proteins and carbohydrates from soybean seed

The stepwise hot water extraction of soybeans, which were extractions in a series of procedures of whole soybean seeds, dehulled and sliced ones, and pressed ones carried out by autoclaving, was investigated to study the localization in the seed and their characteristics. The characteristics of each extraction were studied by HPLC, SDS-PAGE, components analysis, microscopic observation, and effect for some enzymes. Carbohydrates were easier to extract than protein. In the extractions, the ratio of uronic acid per total sugar was constantly about 0.3. A comparison of these extracts, soybean milk, extraction from defatted soybean meal, and soybean milk residues was also carried out, and the characteristics and the localization were investigated. Mid-sized proteins in soybean milk were easy to extract. However, hardly any high molecular weight proteins or high molecular weight carbohydrates were extracted. The proteins and carbohydrates were considered to be localized in the middle lamella and in the protein and/or oil bodies of the cell, and the proteins and carbohydrates were gradually extracted through seed and cell breaking. Gelation was observed only in the boiled extracts from whole seeds. Pepsin and trypsin digests of the high molecular weight protein had inhibitory activity against the angiotensin I converting enzyme.     

Compositional analysis of glyphosate-tolerant soybeans treated with glyphosate.

The compositional analyses and safety assessment of glyphosate-tolerant soybeans (GTS) were previously described. These analyses were extensive and included addressing the potential effects on seed composition from the genetic modification. Detailed compositional analyses established that GTS, which had not been treated with glyphosate, were comparable to the parental soybean line and to other conventional soybeans. In this study, two GTS lines, 40-3-2 and 61-67-1, were treated with commercial levels of glyphosate, the active ingredient in Roundup herbicide. The composition of the seed from soybeans sprayed with glyphosate was compared to that of a nonsprayed parental control cultivar, A5403. The nutrients measured in the seed included protein, oil, ash, fiber, carbohydrates, and amino acids. The concentration of isoflavones (also referred to as phytoestrogens) was also measured as these compounds are derived from the same biochemical pathway that was engineered for glyphosate tolerance. The analytical results from these studies demonstrate that the GTS soybeans treated with glyphosate were comparable to the parental soybean cultivar, A5403, and other conventional soybean varieties.     

beta-Conglycinin and glycinin in high-protein soybean seeds

The agronomic performance and storage proteins of high seed protein lines of soybeans [Glycine max L. (Merr.)] were investigated to determine if the two major storage proteins, beta-conglycinin and glycinin, contribute to the increased protein content of high seed protein lines. Subunits of these two major storage proteins were estimated by scanning SDS-PAGE gels by scanning densitometry. The relative rankings of the lines with respect to seed size and protein content were not different between years in one environment over 5 years, but oil and total protein and oil contents and the ratio of protein to oil differed. The alpha', alpha, and beta subunits of beta-conglycinin were significantly higher in the high-protein lines except CX797-115, CX804-108, CX804-3, D81-8498, and NC-2-62. The acidic A(3) polypeptide of glycinin was significantly higher in high-protein lines except 76-48773, CX804-108, CX804-3, D81-8498, and NC-2-62, whereas the acidic polypeptides A(1,2,4) of glycinin were significantly higher in all of the high-protein lines. The basic polypeptides of glycinin were significantly higher in all high seed protein lines except D81-8259. In conclusion, high-protein lines appear to contain more beta-conglycinin and glycinin than normal-protein soybean lines, and the amounts of subunits and polypeptides differ among lines.     

Proteomic analysis of high protein soybean (Glycine max) accessions demonstrates the contribution of novel glycinin subunits

Limited biochemical information is available on soybean accessions that have seed protein content greater than 45% of the seed dry weight. SDS-PAGE analysis of seed proteins from nine soybean accessions revealed significantly higher amount of seed storage proteins in these accessions when compared with that of soybean cultivar Williams 82. High-resolution two-dimensional gel electrophoretic analysis of seed proteins revealed significant differences among several seed storage protein components in these accessions. A total of 51 protein spots were identified using peptide mass fingerprinting (MALDI-TOF MS). The contribution of these proteins to the overall protein content of the accessions was quantified using Delta2D image analysis software. Results showed that among the majority of the nine accessions, the largest difference in higher protein quantity was within the seed 11S storage globulins. The high protein trait from PI407788A was successfully transferred to an experimental line, LG99-469, demonstrating that this trait was transferable and robust.     

Assessment of indigenous Nepalese soybean as a potential germplasm resource for improvement of protein in North American cultivars

Soybeans contain approximately 40% protein and 20% oil and represents an important source of protein in animal rations and human diets. Attempts are being made to increase further the overall protein content of soybeans by utilization of exotic germplasms. In this study, soybean cultivars from Nepal have been characterized and their potential as a germplasm resource for improvement of the protein content and quality of North American cultivars assessed. Soybean cultivars 'Sathia', 'Seti', 'Kavre', and 'Soida Chiny', indigenous to various regions of Nepal, contained 42-45% protein, which is significantly higher in comparison to that of the North American cultivar 'Williams 82' (39%). Fractionation of seed protein by high-resolution two-dimensional gel electrophoresis revealed differences in the protein profiles of these cultivars. Various isoelectric forms of glycinin and beta-conglycinin were identified by comparing the matrix-assisted laser desorption ionization time-of-flight mass fingerprinting data against the National Center for Biotechnology Information nonredundant database. Nepalese cultivar Sathia was distinct, lacking some isoelectric forms of acidic and basic glycinin subunits while expressing other unique forms. The contribution of these unique protein spots present in either Sathia or Williams 82 to the total protein content was quantified using scanning laser densitometry. Distinct restriction fragment length polymorphisms (RFLP) for group 1 glycinin genes were observed among the tested Nepalese genotypes, indicating sequence variation among the cultivars. Conversely, evaluation of RFLP for the genes encoding group 2 glycinins, beta-conglycinin, and Bowman-Birk proteinase inhibitors indicated a high degree of conservation in these genes. Determination of amino acid composition, a reflection of protein quality, indicated that the arginine content of the Nepalese soybeans ranged from 7.7 to 8.1%, which was 5-10% higher than the 7.4% expressed in Williams 82. Additionally, Karve and Seti contained significantly more cysteine than Williams 82. Nepalese high-protein soybeans having a desirable amino acid composition hold potential to increase the protein quality and diversity of North American cultivars.     

不同品种花生油脂体粒径电位和蛋白质组成的分析

为了探索不同品种花生油脂体的物理和化学性质差异,以5种（豫花23,豫花27,豫花9719,豫花9830和豫花9502）油脂含量不同的花生品种为原料,采用水剂法提取油脂体,并对提取后油脂体的粒径、ζ电位、氨基酸组成、蛋白质分子量分布进行分析比较。结果表明：提取后,5种花生油脂体粒径间存在一定差异,以豫花9719的粒径较大;花生油脂体均含有油脂体蛋白和贮藏蛋白,但不同品种间存在蛋白质种类的差异;5种花生油脂体在pH值为3.0时ζ电位为正值,在pH值为7.4和pH值为9.0时ζ电位为负值,盐浓度的增加会降低油脂体ζ电位的绝对值;5种花生油脂体的蛋白质均为极性带负电氨基酸质量分数均大于非极性带正电或不带电氨基酸,但氨基酸总量各不相同,以豫花27较低。该研究可为花生油脂体的品质特性研究和应用产品开发提供参考。     

Antioxidant activities of black and yellow soybeans against low density lipoprotein oxidation

Several studies have demonstrated that the daily intakes of soy foods were associated with a reduced cardiovascular risk. The aim of our study was to investigate the inhibitory effect of black soybeans on low density lipoprotein (LDL) oxidation in comparison to yellow soybeans. The extract from black soybean had a longer LDL oxidation lag time than that from yellow soybean (205 +/- 16 and 65 +/- 3 min, respectively). When both soybeans were divided into the seed coat and the mixture of the germ and cotyledon, the diluted extract solution from the black soybean seed coat prolonged the lag time significantly more than the original extract of the yellow soybean seed coat. On the other hand, antioxidant effects of the extract from the mixture of germs and cotyledons were similar in both soybeans. Regarding total polyphenol contents, the seed coat of black soybean had a higher polyphenol content than that of yellow soybean (29.0 +/- 0.56 and 0.45 +/- 0.02 mg/g, respectively). Interestingly, the mixture of the germ and cotyledon hydrolyzed by beta-glucosidase in both soybeans showed a stronger inhibitory effect on LDL oxidation than that before being hydrolyzed by beta-glucosidase. These results suggest that black soybeans may be more effective in inhibiting LDL oxidation than yellow soybeans because of total polyphenols contents in its seed coat. In addition, aglycones, which are rich in soybeans fermented or hydrolyzed by beta-glucosidase, may play a crucial role in the prevention of oxidation-related diseases.     

Characterization of the soluble allergenic proteins of cashew nut (Anacardium occidentale L.)

The allergens associated with cashew food allergy have not been well-characterized. We sought to identify the major allergens in cashew nut by performing IgE immunoblots to dissociated and reduced or nonreduced cashew protein extracts, followed by sequencing of the peptides of interest. Sera from 15 subjects with life-threatening reactions to cashews and 8 subjects who tolerate cashews but have life-threatening reactions to other tree nuts were compared. An aqueous cashew protein extract containing albumin/globulin was separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and subjected to IgE immunoblotting using patient sera. Selected IgE reactive bands were subjected to N-terminal amino acid sequencing. Each of the 15 sera from cashew-allergic subjects showed IgE binding to the cashew protein extract. The dominant IgE-binding antigens in the reduced preparations included peptides in the 31-35 kD range, consistent with the large subunits of the major storage 13S globulin (legumin-like protein). Low-molecular-weight polypeptides of the 2S albumin family, with similarity to the major walnut allergen Jug r 1, also bound IgE. The sera from eight patients who tolerate cashew but displayed allergies to other tree nuts showed only minimal or no IgE binding to cashew. Cashew food allergy is associated with the presence of IgE directed against the major seed storage proteins in cashew, including the 13S globulin (legumin group) and 2S albumins, both of which represent major allergen classes in several plant seeds. Thus, the legumin-group proteins and 2S albumins are again identified as major food allergens, which will help further research into seed protein allergenicity.     

Influence of cultivar and fruit ripening on olive (Olea europaea) fruit protein content, composition, and antioxidant activity

Proteins of olive fruit mesocarp are not very well-known at present. However, they have been shown to pass, at least partially, to the olive oil during its elaboration and therefore might be contributing to some of the special characteristics of this vegetable oil. In this study, protein content and composition were determined in olive fruits, cv. Arbequina and Picual, at three stages of ripening: green, spotted, and purple. Mesocarp proteins constituted 1.3-1.8% of the dry weight of the olive fruit, and cultivar and fruit ripening did not produce important changes in mesocarp protein content or composition. In addition, this composition was also similar to the amino acid composition of a 4.6-kDa polypeptide, which is the major protein component of olive oils and of oil bodies of olive fruit mesocarp, suggesting that this polypeptide is likely to be a major component of mesocarp proteins. There was, also, a relationship between the oil content of the olive fruit and the protein content determined, suggesting a stabilizing function of these proteins in the oil bodies of the olive fruit, analogously to the role suggested for oleosins. This stabilizing function does not seem to be extended to olive oils because when the polypeptides isolated were added at 20 ppm to soybean oil, the stability of the oil increased only slightly, suggesting that if these compounds play some role in the stability of the oils, this should be mostly a consequence of the possible interactions among these protein components and other olive oil antioxidant constituents.     

Stabilization of soybean oil bodies using protective pectin coatings formed by electrostatic deposition

Soybeans contain oil bodies that are naturally coated by a layer of phospholipids and proteins. In nature, this coating protects the oil bodies from environmental stresses and could be utilized by food manufacturers for the same purpose. However, natural oil bodies are physically unstable to aggregation because of the relatively weak electrostatic repulsion between them, which limits their application in many foods. In this study, oil bodies were extracted from soybean using an aqueous extraction method and then coated by a pectin layer using electrostatic deposition. The influence of NaCl (0-500 mM), pH (2-8), and freeze-thaw cycling (-20 degrees C, 22 h/40 degrees C, 2 h) on the properties and stability of the oil bodies coated by the pectin layer was analyzed using zeta-potential, particle size, and creaming stability measurements. These results suggest that pectin-coated oil bodies have similar or improved stability compared to uncoated oil bodies and may provide a new way of creating functional soy products for use in the food and other industries.     

我国大豆产能现状分析与提升路径探讨

大豆是重要的粮食和经济作物，是植物蛋白和植物油的主要来源，也是禽畜养殖业的主要饲料蛋白来源。我国作为世界第一大豆消费国，85%的大豆需要依赖进口，对国家粮食安全构成严重威胁。为探讨提升我国大豆产能的路径，振兴大豆产业，保障国家粮食安全提供参考，通过查阅文献与生产实际相结合的方法，针对我国大豆单产水平低、总产量不足，种植面积小、提升空间有限，大豆生产成本高、效益低，种植补贴政策不完善等影响大豆产业发展的问题，提出促进我国大豆产能提升的途径:从产量突破性品种培育、栽培技术改进和高产竞赛方面依靠科技进步提高大豆单产；从东北地区大豆面积恢复、西北地区大豆种植、盐碱地开发利用、大豆玉米带状复合种植推广等方面多渠道扩大大豆种植面积；完善大豆补贴及保险政策；从产教融合上提升人才培养质量，振兴大豆产业。     

Antioxidant capacity of seed coat, dehulled bean, and whole black soybeans in relation to their distributions of total phenolics, phenolic acids, anthocyanins, and isoflavones

Black soybeans have been used as an excellent dietary source for disease prevention and health promotion in China for hundreds of years. However, information about the distribution of health-promoting phenolic compositions in different physical parts of black soybean and the contribution of phenolic compositions to overall antioxidant capacity is limited. To elucidate the distribution of phenolic composition and their contribution to antioxidant activities in black soybean, the total and individual phenolic profiles, and antioxidant capacities of seed coat, dehulled and whole black soybean were systematically investigated. The seed coat exhibited much higher total phenolic indexes and antioxidant activities than whole and dehulled black soybean. Dehulled black soybean possessed similar levels of total phenolic content, total flavonoid content, 2-diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) activities as compared to whole yellow soybean. Cyanidin-3-glucoside, petunidin-3-glucoside, and peonidin-3-glucoside were detected in the seed coat but not in dehulled black soybean and yellow soybean. Among benzoic acid detected, caffeic and chlorogenic acid were the predominant phenolic acids. Whole black soybean and dehulled black soybean exhibited similar isoflavone contents in 7- O-beta-glucosides and malonylglucosides of daidzein and genistein. The seed coat possessed significantly ( p < 0.05) lower 7- O-beta-glucosides and malonylglucosides of daidzein and genistein, acetylglycitin, and total isoflavones than whole and dehulled black soybean. The contribution of phenolics in the seed coat to the antioxidant activity of black soybean parts depends on the assay methods. When measured with the DPPH and FRAP methods, the seed coat contributed 90% of the total antioxidant capacity of black soybean. However, when measured with the ORAC method, the seed coat and dehulled portion contributed approximately equally the total antioxidant capacity of black soybeans. The information generated from this study on the distribution and content of their active components is useful for the effective use of black soybeans as an ingredient for promoting health.     

Nutritional quality of sesame seed protein fraction extracted with isopropanol

The nutritional effect of diet containing decorticated sesame seed extracted with isopropanol (DSS-Iso) was evaluated on growth performance, food efficiency ratio, plasma and tissue lipid profile, plasma protein content, and erythrocyte membrane lipid profile of rats on a comparative basis with diets containing casein (control), soybean meal, and decorticated sesame seed extracted with hexane (DSS-Hex). Rats fed a DSS-Iso-based diet showed body weight gain and food efficiency ratio similar to those of the control groups fed diets prepared with casein, soybean meal, and DSS-Hex. However, dietary proteins exerted a separate effect on plasma lipid concentrations of the rats. Rats fed a DSS-Iso-based diet showed significant decreases in plasma total cholesterol (p < 0.01), triglyceride (p < 0.01), and VLDL+LDL cholesterol (p < 0.01) concentrations in comparison to the rats fed diet containing casein. No significant differences in plasma lipid concentrations were observed for the rats fed diets prepared with soybean meal, DSS-Hex, and DSS-Iso. Rats fed the different dietary proteins did not show much variation in plasma proteins, liver lipids, and erythrocyte membrane lipid concentrations, which suggests that DSS-Iso could be a suitable edible protein like casein or soybean meal.     

Extraction of soybean oil from single cells

Single cells prepared from autoclaved soybeans and cellulase treatment of the cells were effective in digesting the cell walls of and extracting the oil from soybeans. The first cell wall of the soybean single cell was completely removed using cellulases; the thin and transparent second cell wall of the cell was swollen. Oil in the cell formed spherical or hemispherical oil drops, and oil leaking from the oil bodies was observed. The oil was almost retained within the second cell wall. Water-extractable substances were obtained at approximately >60% of the weight. Flotation of oil drops by centrifugation was easily done. Ambient n-hexane extraction was also possible; however, residual oil remained in the oil bodies. Protease or peptidase digested the structure of the oil bodies; however, separation of the oil and the hydrolysates was impossible. The oil from the oil bodies was obtained effectively (>85%) by pressing the single cells and/or cellulase-treated single cells.     

Quantification and sensory studies of character impact odorants of different soybean lecithins.

Fifty-four potent odorants in standardized, hydrolyzed, and deoiled and hydrolyzed soybean lecithins were quantified by high-resolution gas chromatography/mass spectrometry (HRGC/MS). The characterization of their aroma impact was performed by calculation of nasal (n) and retronasal (r) odor activity values (OAVs). For this, the nasal and retronasal recognition thresholds of 18 odor-active compounds were determined in vegetable oil. The following compounds showed the highest nOAVs: 2,3-diethyl-5-methylpyrazine, methylpropanal, acetic acid, pentanoic acid, 2-ethyl-3,5-dimethylpyrazine, pentylpyridine, (Z)-1,5-octadien-3-one, 2-methylbutanal, and beta-damascenone. In addition to the compounds above, 1-octen-3-one, 1-nonen-3-one, and 3-methyl-2,4-nonandione showed potent rOAVs. The results of quantification and OAV calculation were confirmed by a model mixture of 25 impact odorants, which yielded a highly similar sensory profile to that of the original soybean lecithin. The sensory importance of pyrazines and free acids increased through enzymatic hydrolysis and decreased by the process of deoiling. The impact of unsaturated ketones on the lecithin aroma was not changed by either process.