Analyses of Protein and Oil of Maize Offsprings Plants Introducing Soybean DNA

[Objective] The experiment was aimed to explore character variation between different families after DNA introduction and select variant plants with good stability. [Method] The method of pollen-tube-pathway was used to introduce total DNA of soybean into normal maize inbred line 7313 for selecting generation by generation. When field characters of maize, grain colors, grain traits and panicle axis colors were stable, the crude protein, gliadin, glutelin and oil content of grains which were selected from variant strains were detected and compared. [Result] The grain crude protein, gliadin, glutelin and oil content of line 26h-4-3 were significantly different from these of control treatment. The increments of D3 and D4 generation were 10.34% and 26.70%, 6.58% and 6.28%, 15.09% and 70.34%, 55.82% and 51.52% respectively. All indexes of line 26h-3-1 were also higher than these of control treatment and the increments of D3 and D4 generation were 5.67% and 21.63%,1.91% and 2.31%, 10.85% and 62.27%,22.49% and 9.67%. [Conclusion] The crude protein, gliadin, glutelin and oil content of variant line 26h-4-3 and 26h-3-1 were stable, so variant line 26h-4-3 and 26h-3-1 were excellent variant strains which satisfied the requirement of high protein breeding.

Effects of chelating agents on protein, oil, fatty acids, and minerals in soybean seed

Soybean seed is a major source of protein and oil for human diet. Since not much information is available on the effects of chelating agents on soybean seed composition constituents, the current study aimed to investigate the effects of various chelating agents on soybean [(Glycine max (L.) Merr.)] seed protein, oil, fatty acids, and mineral concentrations. Three chelating agent [citric acid (CA), disodium EDTA (DA), and Salicylic acid (SA)] were applied separately or combined with ferrous (Fe2+) ion (CA + Fe, EDTA + Fe, and SA + Fe) to three-week-old soybean plants. After application, the plants were allowed to grow until harvest maturity under greenhouse conditions. The results showed that CA, DA, SA, and Fe resulted in an increase of oleic acid from 13.0% to 33.5%. However, these treatments resulted in a decrease of linolenic acid from 17.8 to 31.0%. The treatments with CA and SA applications increased protein from 2.9% to 3.4%. The treatments DA + Fe and SA + Fe resulted in an increase in oil from 6.8% to 7.9%. Seed macro- and micro-elements were also altered. The results indicated that the CA, SA, DA, and Fe treatments can alter seed protein, oil, fatty acids, and mineral concentrations. Further studies are needed for conclusive results.

Effect of Shade on Seed Protein, Oil, Fatty Acids, and Minerals in Soybean lines Varying in Seed Germinability in the Early Soybean Production System

The cause of poor seed quality (germination) of soybean produced in the Early Soybean Production System in the midsouth U.S.A. is still not completely understood. Temperature, solar radiation, and soybean genotype may all be important factors involved. The objective of this research was to evaluate seed composition, mineral level, and nitrogen assimilation in high and low germinability soybean plant introductions in a full-sunlight (unshaded) and a low-light intensity (shaded) environments. Shade netting was employed in field plots that reduced light intensity by about 50% and air temperature by about 10?F/6?C (10%). A two-year field experiment was conducted on soybean accessions with high germinability (PI 587982A and PI 603723), low germinability (PI 80480 and PI 84976-1), and on soybean cultivars (DSR-3100 RR STS and Pella 86). Results showed that shade resulted in higher total oil, linoleic and linolenic acids, and lower protein and oleic acid. Shade also resulted in lower nitrogen assimilation, leaf chlorophyll concentration, but unshade resulted in higher total seed boron, iron, and nitrogen concentrations. Seed structural boron was positively correlated with germination and protein. Structural boron percentage was consistently higher under shade than under unshade in PI 80480, PI 84976-1, DSR-3100 RR STS, and Pella 86, but consistently higher under unshade than under shade in higher germinability lines PI 587982A and PI 603723, suggesting that different distribution mechanisms of structural boron exist between genotypes. The positive correlation between germination and structural B and between protein and structural B signify a possible role of B in seed quality traits. Our research demonstrated that light intensity, combined with temperature, can alter seed constituents. Higher germinability lines had higher germination rates and lower percentages of hardseededness, desirable traits for soybean seed.

Seed protein, oil, fatty acids, and minerals concentration as affected by foliar K-glyphosate applications in soybean cultivars

Previous studies showed that glyphosate (Gly) may chelate cation nutrients, including potassium (K), which might affect the nutritional status of soybean seed. The objective of this study was to evaluate seed composition (protein, oil, fatty acids, and minerals) as influenced by foliar applications of K + Gly. A greenhouse experiment was conducted at Mississippi Valley State University, using two glyphosate-resistant soybean cultivars DK 4968 and Pioneer 95Y70 grown in a randomized complete block design. The treatments were foliar applications of K alone, Gly alone, K + Gly combined, and nontreated control (C). A single application of potassium (1.75% as K2SO4) was applied, and Gly was applied at a rate of 0.75 ae/ha at V5 stage. Leaf samples were harvested one week after treatment (1WAT) and 3WAT. Mature seeds were collected at harvest maturity (R8). The results showed that K, nitrogen (N), and phosphorus (P) concentrations increased in leaves in K alone and K + Gly treatments at 1WAT, but significantly increased at 3WAT in all treatments. The concentration of iron (Fe) and zinc (Zn) showed a decrease in leaf concentration in Gly and K + Gly treatments compared to C. Boron (B) concentration increased in Gly treatment. Seed protein percentage was higher in all treatments in cultivar DK 4968, and the increase was about 4.0% in K treatment, 6.9% in Gly treatment, and 3.5% in K + Gly treatment compared to C. The opposite trend was observed in oil concentration, especially in Gly treatment where the percentage decrease was 11.2% compared to C. Stearic fatty acid was significantly higher in K + Gly treatment compared to K treatment for DK 4968. A higher percentage increase in linolenic acid was observed in DK 4968 in K treatment (an increase of 24.5%) and in K + Gly treatment (an increase of 29.5%) compared to C. In Pioneer 95Y70, the decrease in oil was 2.7% in K treatment and 2.3% in K + Gly treatment compared to C. Stearic acid in Pioneer 95Y70 was significantly higher in Gly treatment, an increase of 8.3%, compared to C. Our research demonstrated that foliar application of K and Gly altered mineral concentration in leaves and shifted seed composition towards protein and stearic concentration. Further research under field conditions is needed before final conclusions are made.

Soybean seed protein, oil, and fatty acids are altered by S and S + N fertilizers under irrigated or non-irrigated environments

Information on the effect of sulfur (S) or sulfur+nitrogen (S + N) on soybean seed composition is scarce. Thus, the objective of this study was to investigate the effects of S, and S + N fertilizers on soybean [(Glycine max (L.) Merr.)] seed composition in the Early Soybean Production System (ESPS) under irrigated (I) and nonirrigated (NI) environments. Two separate field experiments were conducted from 2005 to 2007. One experiment was irrigated, and the second experiment was nonirrigated. Under I condition, S at a rate of 44.8 kg/ha alone or with N at 112 kg/ha resulted in a consistent increase in seed protein and oleic acid concentrations, and a decrease in oil and linolenic acid concentrations compared with the control (C). For example, in 2006 and compared with the C, application of S + N increased the percentage up to 11.4% and 48.5% for protein and oleic acid, respectively. However, oil concentration decreased by 3%. Protein and oleic acid increase were accompanied by a higher percentage of leaf and seed N and S. Under NI conditions, seed protein and oleic acid concentrations were significantly higher in C than in any S or S + N treatments, but the oil and linolenic acid concentrations were significantly lower. The results indicate that specific rate of S alone or S + N combined can alter seed composition under irrigated or nonirrigated conditions. This knowledge may help plant breeders to develop and release cultivars to suit specific target locations to grow new value-added soybeans or select for specific seed composition traits under specific environmental stress factors such as drought.

Phosphorus Fertilization Differentially Influences Fatty Acids, Protein, and Oil in Soybean

Information is limited about phosphorus (P) fertilization effects on soybean seed composition. A field experiment was conducted to investigate the effects of P application rates on the concentrations of various fatty acids, protein, and oil in soybean under no-tillage on low and high testing P soils at Jackson and Milan, Tennessee from 2008 through 2011. Five P rates 0, 10, 20, 30, and 40 kg·P·ha-1 plus the recommended P fertilizer rate based on soil P testing results were arranged in a randomized complete block design with four replicates. Protein, oil, and fatty acid concentrations in seed responded differently to P fertilization. In general, protein concentrations were enhanced but oil levels decreased with increased P application rate. Palmitic and oleic concentrations responded positively to P application rate up to a certain level. However, the response of linolenic acid concentration was inconsistent (negative or positive). Stearic concentration was not influenced by P fertilization. Application of 10 kg·P·ha-1 resulted in higher production of protein and palmitic, oleic, and linolenic acids than zero P and the higher P application rates as well on the P deficient soil. Excessive P application rates could lower seed yield and the quality of some attributes in seed. In conclusion, linoleic acid concentration, a key quality attribute in soybean seed for human and animal consumption, can sometimes be enhanced by P fertilization;the indigenous soil P level and P application rate should be taken into account in breeding soybean cultivars with low linolenic acid level.

Soybean seed protein, oil, fatty acids, and mineral composition as influenced by soybean-corn rotation

Effects of crop rotation on soybean (Glycine max (L) Merr.) seed composition have not been well investigated. Therefore, the objective of this study was to investigate the effects of soybean-corn (Zea mays L.) rotations on seed protein, oil, and fatty acids composition on soybean. Soybeans were grown at Stoneville, MS, from 2005 to 2008 in five different scheduled cropping sequences. In 2007, following three years of rotation with corn, seed oleic acid percentage was significantly higher in any crop rotation than continuous soybean. The increase of oleic fatty acid ranged from 61 to 68% in 2007, and from 27 to 51% in 2008, depending on the rotation. The increase of oleic acid was accompanied by significant increases in seed concentrations of phosphorus (P), iron (Fe), and boron (B). In 2007, the increase of P ranged from 60 to 75%, Fe from 70 to 72%, and B from 34 to 69%. In 2008, the increase of P ranged from 82 to 106%, Fe from 32 to 84%, and B from 62 to 77%. Continuous soybean had higher linoleic:oleic ratio and linoleic: palmitic + stearic + oleic ratio, indicating that relative quantity of linoleic acid decreased in rotated crops. The total production of protein, oil, stearic and oleic fatty acids was the lowest in continuous soybean. The total production of palmitic acid was inconsistent across years. The results show that soybean- corn rotation affects seed composition by consistently increasing seed oleic fatty acid, P, Fe, and B concentrations. Higher oleic acid, unsaturated fatty acid, is desirable for oil stability and long-shelf storage. The mechanisms of how these nutrients are involved are not yet understood.

Identification of seed protein and oil related QTL in 944 RILs from a diallel of early-maturing European soybean

Soybean[Glycine max(L.)Merr.]is a global protein source and is currently expanding in Central and Northern Europe.Protein and oil content are two important quality traits that have been studied in different germplasm,however,their genetic architecture in earlymaturing European soybean has not been investigated yet.In this study,we therefore performed QTL mapping for both traits using 944 recombinant inbred lines derived from eight families from a half-diallel crossing design.We identified five QTL for each trait,with the QTL on chromosomes 8,15,and 20 being identified for both protein content and oil content.The known major QTL on chromosome 20 was detected in four families whereas the other QTL were only found in single families.Further analyses revealed the QTL to have pleiotropic but inverse effects on both traits.The effect of the major QTL was comparable between families,illustrating that it is largely independent from the genetic background.Collectively,our results illustrate the quantitative nature of protein and oil content in early European soybean.Marker-assisted selection for the QTL is possible,but the inverse effect on protein and oil content should be kept in mind.

The Role of Metal Ions in Protein and Fatty Acids Biosynthesis in Soybean under Micronutrients Application to Soil

The present study is part of our ongoing investigation to study the role of trace elements on soybean seed composition (protein, oil, and fatty acids). This study was conducted to study the effects of five trace elements (Mn, Cu, Zn, Mo, B). The treatments of Mn, Cu, Zn, Mo, and B were chlorides, except Mo as oxide, and B as boric acid. The treatments were Mn, Cu, Zn, Mo, and B alone and in combination with the chelating agent citric acid (CA), for example Mn + CA, Cu + CA, and Zn + CA. Soybean cultivar (Bolivar with maturity group V) was grown in a repeated greenhouse experiment in a randomized complete block design. The compounds were applied to three-week-old soybean plants at V3 (vegetative) and at R3 (beginning of seed-pod initiation) stages. The plants were allowed to grow until maturity under greenhouse conditions. The harvested seeds were analyzed for mineral, protein, and fatty acid contents. Results showed that Mn, Cu, and B treatments increased seed protein, while Zn, Mo, Cu + CA, and B + CA decreased the protein. Treatments of Zn, Mo, CA, Cu + CA, Zn + CA, Mo + CA, and B + CA increased the oil. Treatments of Mn and Cu decreased the oil. The Cu and B treatments increased oleic acid by 8.0% and 7.4%, respectively for Cu and B. Treatments of Mn, Mo, CA, and Mn + CA, Cu + CA, Zn + CA, Mo + CA, and B + CA decreased oleic acid by 0.6% to 14.4%. Treatments of Cu, Zn, Mo, B, CA, Mn and their combination with CA increased linoleic acid by 1.3% to 6.5%. Our goal was to identify the trace elements that would make desirable alteration in the seed composition qualities.

Comparative effects of soy protein concentrate,enzyme‑treated soybean meal,and fermented soybean meal replacing animal protein supplements in feeds on growth performance and intestinal health of nursery pigs

Background Soy protein supplements,with high crude protein and less antinutritional factors,are produced from soybean meal by different processes.This study evaluated the comparative effects of various soy protein supplements replacing animal protein supplements in feeds on the intestinal immune status,intestinal oxidative stress,mucosaassociated microbiota,and growth performance of nursery pigs.Methods Sixty nursery pigs(6.6±0.5 kg BW)were allotted to five treatments in a randomized complete block design with initial BW and sex as blocks.Pigs were fed for 39 d in 3 phases(P1,P2,and P3).Treatments were:Control(CON),basal diet with fish meal 4%,2%,and 1%,poultry meal 10%,8%,and 4%,and blood plasma 4%,2%,and 1%for P1,P2,and P3,respectively;basal diet with soy protein concentrate(SPC),enzyme-treated soybean meal(ESB),fermented soybean meal with Lactobacillus(FSBL),and fermented soybean meal with Bacillus(FSBB),replacing 1/3,2/3,and 3/3 of animal protein supplements for P1,P2,and P3,respectively.Data were analyzed using the MIXED procedure in SAS 9.4.Results The SPC did not affect the BW,ADG,and G:F,whereas it tended to reduce(P=0.094)the ADFI and tended to increase(P=0.091)crypt cell proliferation.The ESM did not affect BW,ADG,ADFI,and G:F,whereas tended to decrease(P=0.098)protein carbonyl in jejunal mucosa.The FSBL decreased(P<0.05)BW and ADG,increased(P<0.05)TNF-α,and Klebsiella and tended to increase MDA(P=0.065)and IgG(P=0.089)in jejunal mucosa.The FSBB tended to increase(P=0.073)TNF-α,increased(P<0.05)Clostridium and decreased(P<0.05)Achromobacter and alpha diversity of microbiota in jejunal mucosa.Conclusions Soy protein concentrate,enzyme-treated soybean meal,and fermented soybean meal with Bacillus could reduce the use of animal protein supplements up to 33%until 7 kg body weight,up to 67%from 7 to 11 kg body weight,and entirely from 11 kg body weight without affecting the intestinal health and the growth performance of nursery pigs.Fermented soybean meal with Lactobacillus,however,increased the immune reaction and oxidative stress in the intestine consequently reducing the growth performance.

Extruded Soybean Samples for Mechnical Oil Expression

Soybean is generally recognized as a source of edible and the deoiled meal is seen as a source of protein in animal feed.In recent years.However,more interest has been directed toward using soy meal as a protein souce for human consumption.Extrusion expelling of soybean provides an opportunity in this direction.The main focus of this study was to maximize the oil recovery from extruded soybean processed using three different kinds of extrudates and processing conditions.These extruded samples were later pressed uniaxially in a specifically designed test cell and the oil recovery was recorded over time.The effects of process variables,including applied pressure,pressing temperature and sample height,were investigated.Results indicated that over90% of the available oil could be recovered from pressing of extruded soy samples.The information generated is likedly to be useful in interpreting the effect of precess variables and extruding equipment for pretreatment of soybean for subsequent mechanical oil expression.

Consumption of soybean,soy foods,soy isoflavones and breast cancer incidence:Differences between Chinese women and women in Western countries and possible mechanisms

Breast cancer is one of the most lethal diseases world-wide.However,there is a large difference in breast cancer incidence among Caucasian,Hispanic,African and Asian(e.g.Chinese)women with Caucasian women being the highest and Asian women being the lowest.It has been suggested that the dietary factors may account for approximately 50%of the breast cancer.One of such dietary components which are typical to Asian but not Caucasian diet is soy foods.A number of epidemiological studies have suggested that increasing soy consumption could be related to the decreased risk of occurrence and/or mortality of breast cancer.In this review,we first described briefly different types of soy products and their nutritional functions and consumption.Then,we described briefly soybean isoflavones,i.e.genistein(GEN),daidzein,glycitein,and presented several lines of evidence to demonstrate the possible association of soy flavone food consumption with incidence and prognosis of breast cancer;finally,we summarized several possible molecular mechanisms,including the effects of GEN as an agonist of ER,epigenetic and genome-wide effects,activation of peroxisome proliferator-activated receptors,induction of apoptosis and stimulation of autophagy,involved in the chemo-preventive effects of GEN on breast cancer.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.

Relationship between Protein Accumulation Regulation and Yield Formation in Soybean

Three different genotypes soybeans were adopted in this experiment under three fertilizer levels. The object of this study was to investigate protein accumulation regulation of soybean cultivars under the condition of different nutrient levels, and their effects on soybean yield and quality, and to provide theoretical evidence for breed, cultivation and agricultural production, also man-powered controllable locations. The concentration of N in the leaves declined after seedling stage, then increased again at stage of early flowering, and started to decrease up to leaf senescence, declined rapidly from seed-filling season to stage of yellow ripeness. The concentration of N in the stems and pod walls declined with growth stage. High seed protein genotypes exhibited higher N assimilating and partitioning during whole growth stages. Pod walls were media of N partitioning. Protein was accumulated mainly during the later period of reproductive growth stage up to harvest, so plant growth after stage of yellow ripeness could not be neglected.

Effect of pulse drip irrigation and mulching systems on yield, quality traits and irrigation water use efficiency of soybean under sandy soil conditions

Two field experiments were carried out during growing seasons 2010 and 2011, it executed in research farm of national research center in Nubaryia region, Egypt to study the effect of pulse drip irrigation and mulching systems for saving water, increasing and improving yield of soybean. The study factors were, pulse drip irrigation technology (adding of daily water requirements on 4 times, 8 times, 12 times compared with adding of daily water requirements on 1 time) and mulching systems (covering the soil with black plastic mulch “BPM”, rice straw mulch “RSM” and the control treatment was soil surface without mulch “WM”). The following parameters were studied to evaluate the effect of pulse drip irrigation and mulching systems: 1) Soil moisture distribution in root zone, 2) Growth characters of soybean plant, 3) Yield of soybean, 4) Irrigation water use efficiency of soybean “IWUE soybean”, and 5) Oil content and oil yield, 6) Protein content and protein yield, 7) Economical parameter. According to the economical view and the results of statistical analysis for effect of pulse drip irrigation and mulching systems on yield, quality traits and IWUE soybean indicated that, applying the irrigation requirements on 8 pulses/day with using BPM is the best conditions because under these conditions was occurred the highest value of yield, quality traits and IWUE soybean and there was significant deference between this case and other treatments. Where, pulse irrigation technique increase from water movement in horizontal direction than vertical direction hence improve from soil moisture distribution and wetted soil volume in root zone and using BPM decrease from evaporation process rate from soil surface hence decreasing of salts accumulation in addition to decreasing of weed growth in the root zone. All traits at AIR on 12 pulses/ day are decreased by increasing of pulses, this may be due to irrigation water was very small with every pulse at AIR on 12 pulses/day in addition increasing the total time of time-off, this mean, un-sufficient application for irrigation water to remove water stress in the root zone.

The Eco-Geographical Distribution of Chemi-cal Composition of Soybean Seeds

The expression of protein and oil content of soybean seeds in worldwide was studied. The results shown that: Latitude and year's weather conditions affected protein content of soybean seeds importantly. Elevation affected oil content significantly. There was important difference in protein / oil content among different eco - geographical regions. The zone, in which there was the highest content of protein / oil, was that one with latitude from 0°to 20°59′ . And in this zone, there were different elevation regions, in which protein or oil content was the highest. For high pro-tein, it was the elevation region with 500 - 1000 m; for oil, it was 0~ 500 m. Protein / oil content was also different among different years. However, the changing range among years in Tropical and Subtropical regions was smaller than that in Temperate Regions. The relationship between protein / oil content and latitude, elevation or soil pH in the regions outside the Tropic of concerned and the Tropic of Capricorn was more significant than that in the region inside Regression Lines, i. e. Equatorial Rainforest and Tropical Grassland regions.

Regulation of seed traits in soybean

Soybean (Glycine max) is an essential economic crop that provides vegetative oil and protein forhumans, worldwide. Increasing soybean yield as well as improving seed quality is of great importance.Seed weight/size, oil and protein content are the three major traits determining seed quality, and seedweight also influences soybean yield. In recent years, the availability of soybean omics data and thedevelopment of related techniques have paved the way for better research on soybean functionalgenomics, providing a comprehensive understanding of gene functions. This review summarizes theregulatory genes that influence seed size/weight, oil content and protein content in soybean. We alsoprovided a general overview of the pleiotropic effect for the genes in controlling seed traits andenvironmental stresses. Ultimately, it is expected that this review will be beneficial in breedingimproved traits in soybean.

天然皂皮皂苷与大豆分离蛋白协同构建高蛋白减脂植物基蛋黄酱及其特性

本研究利用天然皂皮皂苷(Quillaja saponin,QS)与大豆分离蛋白(soybean protein isolate,SPI)稳定乳液凝胶的协同效应构建高蛋白、减脂的植物基蛋黄酱(plant-based mayonnaise,PM)。利用静态光散射、激光共聚焦、低形变流变学和质构特性对比分析PM与两种市售蛋黄酱在外观、乳滴粒径大小与分布、硬度、涂抹性、热稳定性和冻融稳定性等方面的特性。结果表明,以10%SPI和0.18%QS或10%SPI、0.18%QS和1%SPI凝胶颗粒(soy protein isolate gel particles,SGPs)为蛋白配料可构建出与商品蛋黄酱在外观、涂抹状态、质构以及流变特性上相媲美的高蛋白减脂PM(10%蛋白质与50%脂肪、11%蛋白质与40%脂肪,以质量分数计)。在该体系中,QS不仅赋予了高蛋白乳化制品黏度稀化的质构调节性,还赋予了SPI基乳液凝胶优越的热稳定性和冻融稳定性。本研究可为“高蛋白”“减脂”PM的开发与应用提供理论与技术指导。

大豆分离蛋白-蔗糖酯对不同油脂制备的乳液稳定性的影响

为探究复合乳化剂对不同油脂乳化效果的影响,以大豆分离蛋白(SPI)和蔗糖酯(SE)为复合乳化剂,猪油(LA)、大豆油(SO)、亚麻籽油(LO)、鱼油(FO)为油相制备乳液。通过测定乳液的乳化活性、结构特性、热特性、稳定性等指标,研究了不同油相制备的乳液之间稳定性的差异。结果表明,四种乳液中乳液_(LA)有最高的乳化活性和乳液稳定性(27.374 m_2/g,361.243 min),且其乳液液滴平均粒径(D)最小(8.411±0.670μm)。微观结构结果显示,四种乳液颗粒的均匀性为乳液_(LA)>乳液_(SO)>乳液_(LO)>乳液_(FO)。DSC结果表明,乳液_(LA)熔融时需要最多的能量(ΔH=-57.67±1.28 J/g),而乳液_(FO)的焓值仅为-10.18±0.10 J/g。储藏及氧化稳定性的结果表明,乳液_(LA)的稳定性最佳。油脂中不饱和脂肪酸的差异会影响SPI-SE对乳液的稳定效果,油相的不饱和脂肪酸比例越大、不饱和程度越高,乳液稳定性越差。该结果可丰富SPI-SE在油脂乳化上的研究,为油脂的乳化应用提供一定的参考依据。

大豆分离蛋白制备南极磷虾油水包油乳液的作用

以不同质量浓度大豆分离蛋白(SPI)为乳化剂,利用高速均质和超声波破碎两步法制备了SPI-南极磷虾油水包油乳液,研究了大豆分离蛋白作为乳化剂的作用。结果表明,当SPI质量浓度从2 mg/mL增加到16 mg/mL时,蛋白溶液的界面张力从50.1 mN/m减小到42.8 mN/m,乳化稳定性从95.3%增加到98.4%,发泡稳定性从70.8%显著降低到41%,粒径范围127.3~146.3 nm,界面蛋白吸附量从47%增加到74%,共聚焦和表观观察发现所有样品分布均匀且稳定。在储存期间,吐温20乳液过氧化值从初始的0.555 mmol/kg上升到1.938 mmol/kg,蛋白质量浓度4 mg/mL的SPI乳液过氧化值从初始的0.665 mmol/kg上升到1.170 mmol/kg,表明SPI具有抑制氧化作用的能力。蛋白质量浓度为4 mg/mL的SPI乳液在40、50、60℃的货架期分别为31.4、30.2和29.2 d。

大豆压榨产业链期转现应用场景分析与建议

大连商品交易所(以下简称大商所)豆粕和豆油品种期现货结合程度较高。然而,期转现在我国压榨产业链中的应用仍处于初级阶段。为推动大商所期转现应用,本文对大豆压榨产业链上下游企业的期转现应用现状、难度及可行性进行了分析。一方面,对压榨厂应用芝加哥期货交易所(CBOT)期转现采购大豆进行了分析,总结出压榨利润正套和延期点价两个常用模式。另一方面,对压榨厂应用大商所期转现销售产品进行了分析,总结出交割和交易两个场景,将期货头寸转换方式与相关业务有机结合。同时,本文提出了重点推广基差定价和提前交割两个应用场景、加强市场培育提升产业客户参与度、发挥产业链龙头企业的示范作用和优化期转现操作系统与制度规则四方面建议。