The comparative value of heated ground unextracted soybeans and heated dehulled soybean flakes as a source of soybean oil and energy for the chick

Experiments were conducted to evaluate heated unextracted soybean fractions as sources of soybean oil and protein for the growing chick. Heated dehulled unextracted soybean flakes produced growth rate and feed efficiency equal to that obtained with the combination of soybean oil meal and degummed soybean oil while heated ground unextracted soybeans were less satisfactory in this respect. The poorer results obtained with ground unextracted soybeans were shown to be related to a poorer absorbability of the oil in them. Flaking the soybeans markedly improved the absorbability of the oil by the chick, probably by causing a greater disruption of cellular structure than was obtained by the grinding of the soybeans. The metabolizable energy of ground unextracted soybeans was substantially less than that of unextracted soybean flakes. Most of the differences in metabolizable energy were accounted for by differences in absorbability of the oil. Soybean hulls at a level equivalent to that contained in soybeans were found to have no effect on growth rate and only a slight effect on feed efficiency. Autoclaving soybean oil did not lower its value for the chick. The relationship between the poorer growth obtained with ground unextracted soybeans and the low absorbability of the oil in them was discussed. To obtain maximum efficiency in the use of unextracted soybean products in chick rations, some such means as flaking must first be employed to increase the availability of the oil.     

Carbon-13 nuclear magnetic resonance measurement of oil composition in single viable soybeans

High-resolution, natural abundance¹³C NMR spectra of intact, viable soybeans have been obtained by Fourier transform techniques. The spectra are interpreted in terms of the relative concentrations of the major fatty acids present in the soybean triglycerides. This nondestructive analysis is sufficiently fast and accurate to permit the selection of individual soybeans for use in a genetic breeding program designed to reduce the undesirably high linolenic acid content of soybean oil.     

Oil quality from hydraulic pressed soybeans

Summary HYDRAULIC pressed soybean oil quality is affected a great deal by the moisture of the beans at the time of milling. At moistures above 12 to 13% the oil quality deteriorates sharply. A great improvement in the oil from wet or even moisture damaged soybeans can be made by drying the beans in below 12% before milling. Even badly deteriorated (sample grade) beans have been vastly improved. Blending of wet and dry soybeans to an average moisture below 12% does not seem to yield as good quality oil as drying wet beans to a corresponding moisture. Normal variations in other soybean characteristics determining bean grade have lesser effects on soybean oil quality. Some data on the effect of bean damage, splits, off-color varieties, and foreign material are included in this paper. Hydraulic oil mills operating on soybeans will be able to make large improvements in oil quality by drying whole wet beans at the mill and by removing foreign material from the beans.     

Estimating the processed value of soybeans

Interest in marketing soybeans on the basis of protein and oil content is increasing. Producers, breeders, handlers and buyers of soybeans need a method of evaluating soybean lots of different composition. A model is presented that predicts, given soybean composition and processing conditions, the yield of crude soybean oil and soybean meal from the processing of soybeans in a solvent extraction plant. From these yields, an estimated processed value (EPV) was calculated. For one set of price conditions, the EPV of typical soybeans had a range of $0.93 per bushel if premiums were paid for meal protein in excess of specifications and a range of $0.53 per bushel if meal protein premiums were not paid. Trading rules established by the National Oilseed Processors Association for domestic meal markets have a significant effect on the value and composition of soybean meal.     

Effect of soybean pretreatment on the color quality of soybean oil

Color reversion in soybean oil can be prevented by reducting the enzyme activity of soybeans before cracking and flaking. Soybean oil extracted from steamed, intact soybeans (18% moisture) had lower Rm (max. red) values in RBD oil, higher amounts of γ-tocopherol, plus its isomers, in both crude and RBD oil, and also higher amounts of hydratable phosphatides in crude oil than those in the oils from the same beans without steam treatment. For soybean pretreatments, a toasting process is less effective than the steaming process for the inhibition of color reversion of soybean oil. To prevent the occurrence of color reversion in RBD soybean oil, the amount of γ-tocopherol and γ-TED (5-[tocopheryloxy]-γ-tocopherol) should be above 550 ppm in crude oil.     

Evidence of an Enzymatic Source of Off Flavors in “Lipoxygenase-Null” Soybeans

The utilization of soybean products as food ingredients and foods is often limited by their beany-grassy flavor. Eliminating seed lipoxygenase (LOX) isozymes 1, 2 and 3 reduces the amounts of volatile off-flavor compounds in stored soybeans and soy products significantly, but they are not completely eliminated. The present work presents evidence that lipoxygenase-null (LOX-null) soybeans contain a LOX-like enzyme that is responsible for the off-flavors in LOX-null soybeans. Volatiles production in triple LOX-null soybeans was terminated by heat treatment, which suggests an enzymatic cause to the off-flavors. The source is LOX-like in that the volatile compounds produced are similar to LOX-generated products of polyunsaturated fatty acids. Oxygen was consumed when a LOX-null protein solution was incubated with crude soybean oil suggesting that the enzyme catalyzed oxygen consuming reactions. The generation of flavor compounds was inhibited by the typical LOX inhibitors propyl gallate and nordihydroguaiaretic acid (NDGA). The enzyme appears to be more active with phosphatidylcholine than with other lipid substrates. The cause of the off-flavors in LOX-null beans appears to have enzyme-like characteristics. This is the first report of the initial characterization of this LOX-like enzyme.     

Measurement of fatty acids in whole soybeans with near infrared spectroscopy

Improvement of nutritional and/or functional properties of soybean oil by modification of soy fatty acid composition is one of the objectives of plant breeders. A major element of breeding is rapid identification and tracking of traits in seed samples. This discussion summarizes the progression of whole‐soybean fatty acid calibration developments at Iowa State University. Emphasis was placed on linolenic acid (18:3) and total saturates (16:0 + 18:0). Normal soybeans have 12–20% (of the oil) saturated fats; modified low saturate soybeans have 6–8% saturated fats. Normal soybeans have 6–12% linolenic acid; modified low linolenic soybeans have 1–3% linolenic acid. Infratec 122x/1241 and Bruins OmegaG NIRS units were calibrated to measure fatty acid levels as a percentage of total oil content, in whole soybeans. The first Infratec calibrations (in 1998) did not remain accurate as soybean genetics changed. Iterations of the calibration process yielded calibrations for total saturates and linolenic acid with standard errors of prediction (on 2005 crop samples not included in the calibration pool) of 1.0% percentage points and 0.8% points, respectively. These were sufficient to classify modified versus normal concentrations of the two fatty acids. The NIRS units could not determine the specific percentages within the classes of modified and normal soybeans.     

Chemical composition and lipoxygenase activity in soybeans as affected by genotype and environment

Environmental and genetic influences on the chemical composition and lipoxygenase activity of 24 soybean genotypes (groups IV-S and V) were determined. The soybeans were grown at two climatically different locations within the state of Georgia. Oil and protein contents and fatty acid composition of the oil in soybeans were affected by the environment. Five genotypes from group IV-S has a fatty acid composition of the oil different from the other genotypes in the group. These differences appeared to be genetically controlled. The level of lipoxygenase activity in soybeans also appeared to be genetically controlled and not influenced by the environment. The study indicated that soybean genotypes could be selected for a specific climatic region based on oil fatty acid composition and lipoxygenase activity.     

Toxic weed seed contaminants in soybean processing

Soybeans are subject to potential contamination from toxic weed seeds during harvest, transportation and storage. The more common foreign seeds include those from jimsonweed, cocklebur, nightshade, cowcockle, corncockle, morning glory, castor, pokeweed, and crotalaria. This review addresses itself to the chemistry and toxic principles of these contaminants. Since jimsonweed seeds are probably the most toxic and most prevalent contaminant of soybeans, they are discussed in greatest detail. A gas liquid Chromatographic method for the determination of tropane alkaloids in jimsonweed seeds is described together with the results from analyses of 11 samples found in grain shipments. Results of a nationwide survey of jimsonweed seeds in soybean samples are also included. The fate of jimsonweed seed alkaloids during solvent extraction of contaminated soybeans and alkali Refining of crude oil was investigated. Extraction of a 50:50 mixture of soybeans and jimsonweed seeds with petroleum ether yielded meal and crude oil fractions; chemical analysis showed that virtually all the alkaloids remained in the meal. Alkali refining effectively removed atropine added to crude soybean oil.     

Soybean drying in fluidized bed. effect on the hydratable and nonhydratable phosphatide concentration in crude and degummed crude oil

The content of nonhydratable phosphatides in soybean crude oil is increased by phospholipase D activity during the oil-making process. Enzyme inhibition would allow to minimize them. Recently harvested soybeans with high moisture levels require adequate drying to store safely. Simultaneous soybean drying and phospholipase D inactivation in a single operation when applying a thermal treatment by the fluidized-bed technique was evaluated. The process conditions for performing the drying and a complete enzyme inhibition on soybeans, with an initial moisture content between 7.4 and 20.6% wet basis, similar to that at the time of the harvest, were fluidizing and drying medium temperature between 110 and 140°C, and a drying time between 1 and 2 min. For the treated soybeans, the phosphorus content increased up to 223% in crude oil and decreased 17% in degummed crude oil with regard to the values of the control sample.     

Fate of jimsonweed seed alkaloids in soybean processing

The fate of Jimsonweed seed alkaloids (atropine and scopolamine) during solvent extraction of contaminated soybeans and alkali refining of crude oil was investigated. Extraction of a 50:50 mixture of soybeans and Jimsonweed seeds with petroleum ether yielded meal and crude oil fractions, in which chemical analyses showed that vitrually all the atropine and scopolamine remained in the meal. Alkali refining effectively removed atropine added to crude soybean oil.     

Single Soybean Seed NMR Calibration for Oil Measurement Using Commercial Cooking Oils

Development of high oil soybeans would reduce the cost of soybean oil production for biodiesel or edible oil applications. An accurate determination of soybean seed oil concentration is essential especially when developing superior cultivars with increased seed oil content. The objective of this study was to develop an oil measurement method for single seeds using NMR spectrometry. An NMR spectrometer was calibrated using commercial cooking oil. Fifteen cultivars of known mean oil content were used to evaluate the calibration curves. The calibration curves developed had a correlation coefficient of 0.99. It was found that soybean and corn oil gave identical results over the calibrated interval.     

Quality of US Soybean Meal Compared to the Quality of Soybean Meal from Other Origins

Quality of soybeans and soybean meals (SBM) from non-US and US origins were compared. The US SBM was more consistent with higher digestibility (by KOH solubility), lower fiber and better quality of protein (by essential amino acid levels) than SBM of other major export origins (Argentina, Brazil and India). Protein quality carried through from whole soybeans to SBM, for a given origin. While the protein content was higher for the SBM from Brazil, the percentage of total digestible amino acids was highest for the SBM from the US and China. The US SBM had the highest content (total) of five essential amino acids for both poultry and swine feed uses, which when coupled with higher digestibility, would give US meal an advantage in rations balanced on amino acids. The mean particle size for all SBM from all origins was within the desirable range specified by nutritionists. The US soybeans were lower in protein than Brazilian soybeans, but higher than Argentine soybeans. The crude protein disadvantage of US soybeans was offset by higher concentrations of the essential amino acids in the lower protein soybeans. The US soybeans were lower in oil content than soybeans from either of the South American origins. Average protein and oil contents of US soybeans were consistent with the 2003 and 2004 annual soybean quality surveys. The US SBM held an advantage in digestibility and concentration of key amino acids in all three studies.     

The Brazilian soybean situation and its impact on the world oils market

Brazil has come from obscurity to become the worlds second largest producer and exporter of soybeans. Internal crushing has also expanded rapidly and become more specialized in soybean crushing. In 1978 Brazilian soybean crushing capacity reached about 14 million metric tons (MT). Domestic oil and meal price ceilings and bean export restric-tions have had a significant effect on the growth in Brazil’s crushing capacity. Since 1975 exports of both soybean meal and oil have received favored export treatment relative to soybeans. Brazil is likely to continue restrictions on bean exports to ensure availability of beans to their crushers. Brazil’s annual soybean production is likely to grow from the 12 million metric tons in 1977 to over 15 million tons by 1982, with exports of 1-2 million tons. Meal exports are expected to grow by 1-2 million tons and oil exports marginally from 1978 levels by 1982. The long run soybean production will depend on how much expansion occurs in the Central West, where the soil is less fertile and production and transport costs are much higher. Substantial expansion there will require higher world soybean prices, construction of marketing and transportation infrastructure, and subsidization of input costs. 1Journal Paper No. 7507, Indiana Agricultural Experiment Station. Revision of paper presented at the Commodity Oil Markets’ Symposium at the AOCS Meeting, St. Louis, May 1978.     

TILLING-by-Sequencing+ to Decipher Oil Biosynthesis Pathway in Soybeans: A New and Effective Platform for High-Throughput Gene Functional Analysis

Reverse genetic approaches have been widely applied to study gene function in crop species; however, these techniques, including gel-based TILLING, present low efficiency to characterize genes in soybeans due to genome complexity, gene duplication, and the presence of multiple gene family members that share high homology in their DNA sequence. Chemical mutagenesis emerges as a genetically modified-free strategy to produce large-scale soybean mutants for economically important traits improvement. The current study uses an optimized high-throughput TILLING by target capture sequencing technology, or TILLING-by-Sequencing⁺ (TbyS⁺), coupled with universal bioinformatic tools to identify population-wide mutations in soybeans. Four ethyl methanesulfonate mutagenized populations (4032 mutant families) have been screened for the presence of induced mutations in targeted genes. The mutation types and effects have been characterized for a total of 138 soybean genes involved in soybean seed composition, disease resistance, and many other quality traits. To test the efficiency of TbyS⁺ in complex genomes, we used soybeans as a model with a focus on three desaturase gene families, GmSACPD, GmFAD2, and GmFAD3, that are involved in the soybean fatty acid biosynthesis pathway. We successfully isolated mutants from all the six gene family members. Unsurprisingly, most of the characterized mutants showed significant changes either in their stearic, oleic, or linolenic acids. By using TbyS⁺, we discovered novel sources of soybean oil traits, including high saturated and monosaturated fatty acids in addition to low polyunsaturated fatty acid contents. This technology provides an unprecedented platform for highly effective screening of polyploid mutant populations and functional gene analysis. The obtained soybean mutants from this study can be used in subsequent soybean breeding programs for improved oil composition traits.     

World supply and demand situation for oilseeds,oils, and meals

In recent years, the demand for meal has been relatively stronger than for vegetable oils. Thus, we have to get the meal demand if we want to determine the extent of oil production and the requirements of oilseeds. This is true although the average annual increase in world meal consumption has declined from 5.5% during the five seasons ended 1970–71 to probably 3.8% in the following five seasons. The share of soybean meal is predominating and ever increasing from 49% ten years ago to as much as 61% this season. In most seasons, including the current one, soybean oil output is determined by the more rapidly increasing meal demand. It is thus often in surplus supply, specifically at present. The marketing of soybean oil is becoming even more difficult as world supplies of low-cost palm oil and lauric oils are increasing more and more sharply. World supplies of oilseeds are developing in cycles of ca. seven years—three years buildup stocks and four years liquidation. The present expansion period, which ends this season, has been more pronounced owing to last season’s severe economic recession which also affected the consumption of meals and oils/fats. Present prospects for the next five seasons point to a slowing-down of the increase in world production of soybeans, soybean oil, and meal owing to a continuing sharp expansion of supplies of palm oil and lauric oils. This assumes that the general economic activity will more or less stagnate or show only a small expansion during this period.     

Factors affecting the content of tocopherol in soybean oil

The state of soybeans prior to extraction affected the tocopherol content of crude soybean oils. Soybean flakes with a thickness of 0.16–0.33 mm had higher extracted oil yield but a slightly lower tocopherol content of the oils than did cracked beans and thicker bean flakes. Highmoisture content and long storage of soybeans resulted in lower tocopherol content in the crude oils, with moisture content being more important than storage time at decreasing the tocopherol content of oils. Soybean oil from stored beans with 15±1% moisture content led to a more significant decrease in the tocopherol content than did oil from stored beans with low (12%) or high (18%) moisture contents. Soybean flakes contaminated with oxidized oil had a significant effect on the decrease of the tocopherol content in crude oils. The high amount of phospholipids in crude soybean oil might result in a smaller decrease in the tocopherol content of oil during heating.     

Protein and oil patterns in U.S. and world soybean markets

The Japan Oilseed Processors Association provided yearly data showing the average protein and oil content of imported soybeans from the U.S. (No. 2 Yellow and IOM grades), Brazil, Argentina, and the People's Republic of China. Throughout the years 1972–1988, U.S. No. 2 soybeans contained about 1–1.5% less oil than Brazilian soybeans. Recently, the protein content of U.S. soybeans has also fallen behind that of Brazil. U.S. IOM soybeans, a designation based on seed size, contained about 1.5% more protein and about 0.5% less oil than U.S. No. 2 soybeans. Surveys of U.S. soybeans in the years 1986, 1987, and 1988 showed consistent state and regional differences in protein and oil content. Soybeans from northern and western soybean-growing states (North Dakota, South Dakota, Minnesota, Iowa, Wisconsin) contained 1.5–2% less protein and 0.2–0.5% more oil than soybeans from southern states (Texas, Arkansas, Louisiana, Mississippi, Tennessee, Kentucky, Alabama, Georgia, South Carolina, North Carolina). State and regional differences in composition represented differences of up to 25 cents per bushel in Estimated Processed Value for one set of soybean meal and oil prices.     

Long-term soybean composition patterns and their effect on processing

Soybean protein and oil data from eight years of national surveys showed Western Corn Belt soybeans to consistently be one percentage point lower in protein than soybeans from the rest of the nation. There was year-to-year vasiability in protein patterns among other regions. Oil percentages were more variable than protein percentages among different years. Except for the far northern states, which typically produce low protein soybeans, improvement and stabilization of oil content would produce the most certain increases in processor yields. Increased protein would be valuable only if soybean meal were priced to reward protein content in excess of specifications.     

Flavor and oxidative stability of oil processed from null lipoxygenase-1 soybeans

The role played by lipoxygenase in the flavor quality of soybean oil was investigated by comparing the oil processed from special soybeans lacking lipoxygenase-1 (Forrest x P.I. 408251) with the oil from normal (Century) beans. Quality assessment was based on sensory evaluations and on capillary gas chromatographic (GC) analyses of volatiles of the extracted crude, partially processed, and refined, bleached and deodorized oils. In direct comparisons of oil products from the two types of beans, no significant differences were found in either flavor quality or in flavor stability based on total volatiles, and in analyses for 2,4-decadienal. Although thermal tempering did not significantly affect the initial flavor scores of crude and degummed oils from Century and low L-1 soybeans, the initial scores of refined and bleached oils from Century soybeans were significantly improved by this treatment. Similarly, thermal tempering was just as important in producing good quality flour from the special beans lacking lipoxygenase-1 as the flour from normal beans. Therefore, factors other than lipoxygenase-1 appear to affect the food quality of soybean oils and meals.