Chemical composition ofacacia seeds

The seeds of 12 species ofAcacia, although rich in C-18 unsaturated acids (47.9–93.5%), have low oil content (2.5–10.2%). Highest concentration of octadecatrienoic acid was inA. lenticularis (80.3%),A. suma (76.8%) andA. tortilis (71.7%) oils.A. mollissima was rich in octadecadienoic (69.1%) andA. senegal in octadecenoic (42.5%) acids. All the seed oils showed the presence of epoxy 18:1 acid, 0.6–3.8%. The protein content of the processed seed meals ranged from 13.4–37.2%, the highest being inA. senegal. Fiber content varied from 8.8–11.9%.     

Processing of canola meal for incorporation in trout and salmon diets

Canola meals (two commercial meals and one low-heat meal) were processed to reduce fiber content, then washed with selected solvents to reduce the content of antinutritional substances and further concentrate protein. The meals, fiber-reduced meals, and washed meals were used to provide 40% of total protein (26–38% of feed) in the diets of 6-g rainbow trout for 3 weeks or 25% of total protein (21–31% of feed) in the diets of 23-g chinook salmon for 11 weeks. Air-desolventized (low-heat) canola meal, as compared to commercial meal, provided no protein quality advantage in trout feeds. Fiber reduction processing of commercial meal increased meal protein content by 11–16% and reduced crude fiber by 23–50%, but did not have any effect on the quality of protein for trout or salmon. Solvent-washing of fiber-reduced meal improved fish response to canola meal, probably due to reduced glucosinolate content, but possibly also due to reduced sinapine content and alterations in protein availability. Protein concentration was increased by 25–40% by washing, and glucosinolate concentration was reduced by 40–90%.     

The effect of processing conditions on the properties of screw-press cottonseed meal and oil

Summary Processing conditions, particularly cooking procedures, have a marked influence on the chemical properties of screw-pressed meal and oil. Cooking prepared meats at 240–250°F., as in normal mill practice, produced meals with low free gossypol content but at the expense of considerable protein damage. The resultant crude oils showed some color reversion upon storage at 95°F. Dry cooking (7% moisture) at temperatures not exceeding 200°F. gave meals of improved chemical properties, but the crude oils exhibited considerable color reversion on storage. Wet low-temperature cooking (200–210°F.), followed by evaporative cooling, yielded a meal intermediate in quality between that for normal mill practice and dry low-temperature cooking. The crude oils, which corresponded to hydraulic-pressed oil, did not exhibit any appreciable color reversion upon storage at elevated temperatures. The selection of processing conditions, notably cooking, enables wide variations in the distribution of gossypol between meal and oil. The increase in the bleach color of crude oils stored at 95–100°F. was found to be directly related to the initial gossypol content of the crude oils. Presented at 44th Annual Meeting of the American Oil Chemists’ Society, New Orleans, La., May 4–6, 1953. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Service, U. S. Department of Agriculture.     

Characterization of Fractionated Soy Proteins Produced by a New Simplified Procedure

It was possible to fractionate soy protein into two soy protein isolate fractions (>90% protein) enriched in either glycinin or β-conglycinin by using a new simplified procedure (referred to as the Deak procedure) employing CaCl₂ and NaHSO₃. The Deak procedure produced fractions with higher yields of solids, protein, and isoflavones, and similar protein purities as well as improved functional properties compared to fractions recovered by established, more complex soy protein fractionation procedures. The Deak glycinin-rich fraction comprised 15.5% of the solids, 24.4% of the protein, and 20.5% of the isoflavones in the starting soy flour, whereas the glycinin-rich fraction of the established procedure (Wu procedure) comprised only 11.6% of the solids, 22.3% of the protein, and 9.6% of the isoflavones. The Deak β-conglycinin-rich fraction comprised 23.1% of the solids, 37.1% of the protein, and 37.5% of the isoflavones in the starting soy flour, whereas the Wu β-conglycinin-rich fraction comprised only 11.5% of the solids, 18.5% of the protein, and 3.3% of the isoflavones. Protein purities were >80% for both fractions when using both procedures. The Wu procedure produced protein fractions with slightly higher solubilities and similar surface hydrophobicities; whereas, the fractions produced by the Deak procedure had superior emulsification and foaming properties and similar dynamic viscosity behaviors.     

Preparation of 8t, 10t-octadecadienoic acid

Summary Oleic acid was brominated with N-bromosuccinimide, followed by addition of free bromine to the double bond. Upon debromination of the brominated product with zinc in ethanol and fractionation of the resultant ethyl esters, the fractions containing 74–75% of conjugated dienoic acids were combined. The ethyl esters were hydrolyzed; upon irradiation by ultraviolet light of the fatty acids in petroleum ether (40–60°) in the presence of a trace of iodine, and upon cooling, 8t,10t-octadecadienoic acid, m.p. 56–56.5°, was obtained in 15–20% yield. This investigation was supported by research grant No A-1671 from the National Institute of Arthritis and Metabolic Diseases, U. S. Public Health Services.     

Crystallization and fractionation of milk fat

Recent progress in understanding milk fat crystallization and fractionation is reviewed. Extent of fat solidification in butter can be altered by variations in thermal treatment of cream prior to churning. Because of its compositional complexity, milk fat rarely exhibits polymorphism. As with mixtures of closely related triglycerides, milk fat forms solid solutions. A typical milk fat begins melting below −40 C, maximum melting occurs at 15–18 C, and the highest melting fraction appears 20–37 C as a shoulder on the main peak. Dispersion of fat in emulsions increases its tolerance to supercooling, thereby altering the properties and composition of the solid phase. Most studies of milk fat fractionation have used progressive fractional crystallization, either of the melt or of solutions. Both procedures result in fractions showing larger changes in mp than in composition. The high melting glyceride fraction, ca. 5% total fat, influences crystallization out of proportion to concentration. The Alfa-Laval system, using an aqueous suspension of partially crystalline fat, produces two fractions. Typical high melting fractions have softening points ca. 3C higher than the original fat. The softening point of typical low melting fractions is lowered 10 C. Refractionation is easier with the high melting fraction. Melting thermograms of these fractions show them as resembling fractions prepared from melted fat. One of eight papers presented at the Symposium “Milk Lipids,” AOCS Fall Meeting, Ottawa, Canada, September 1972.     

Characterization of the seed oil and meal from apricot,cherry, nectarine,peach and plum

The oil and meal from apricot, cherry, nectarine, peach and plum seeds were characterized for their physico-chemical properties. The wt% seed/fruit ranged from 2.8–7.6% and the wt% kernel/seed ranged from 6.8–31.6%. Kernel moisture ranged from 38.8–72.4%. The proximate composition of whole seeds on a dry weight basis ranged from 1.3–6.9% protein, 0.6–14.5% fat, 51.0–72.3% fiber, 0.4–1.2% ash, and 18.1–27.9% carbohydrate (by difference). The kernels contained 41.9–49.3% fat, and the resulting meals contained 31.7–38.7% protein. The major fatty acids were oleic (52.9–66.3%) and linoleic (26.8%–35.0%). The major essential amino acids were arginine (21.7–30.5 mmoles/100 g meal) and leucine (16.2–21.6), and the predominant nonessential amino acid was glutamic acid (49.9–68.0). The iodine values ranged from 105 to 113, hydroxyl value from 5.5 to 7.0 and the unsaponifiables from 0.56–0.80%. The mineral composition (Cu, Fe, Ca, Mg, Zn, P) was also determined on the meals.     

Column Fractionation of Canola Oil Deodorizer Distillate Using Supercritical Carbon Dioxide

Semi-continuous column fractionation of canola oil deodorizer distillate using supercritical CO₂ (SCCO₂) was carried out to determine the feasibility of value-added processing of this feed material for the recovery of bioactive components such as sterols and tocopherols and to determine the effect of operating conditions [pressure (20, 25 MPa using a temperature gradient of 70–100 °C), temperature (70, 100 °C) and a linear temperature gradient (70–100 °C at 25 MPa)] on extract yield and separation efficiency. Total extract yield increased significantly (p ≤ 0.05) with pressure, whereas at isobaric conditions (25 MPa) the highest yield was obtained at the lowest temperature tested (70 °C). Fractionation efficiency was reflected in the composition of fractions and was affected by operating conditions. Residue composition was determined by extract yield in addition to selectivity. Use of the thermal gradient (70–100 °C) decreased the content of volatiles, free fatty acids and tocopherols while increasing sterol content significantly (p ≤ 0.05) to a level of 40% (GC area %) in the residue obtained at 25 MPa. The findings indicate the potential of canola oil deodorizer distillate as a source of sterols and warrant further research on the countercurrent column fractionation to improve the separation efficiency.     

Sequential Fractionation of Cottonseed Meal to Improve Its Wood Adhesive Properties

For better understanding of the adhesive properties of different fractions of cottonseed protein, cottonseed meals from both glanded and glandless cotton varieties were separated into several fractions. Each meal was sequentially extracted with water and 1 M NaCl solution, or with phosphate buffer and NaCl solution. Adhesives were prepared from the recovered fractions and hot-pressed onto maple veneer strips and tested for their properties. The adhesive strength of the water- and buffer-washed solid fractions (i.e., the un-extractable residues of the meals) from the glanded seed ranged from 1.32 to 1.62 MPa and were unchanged or increased compared with the adhesive strength of the original meal that varied from 0.98 and 1.49 MPa. Soaking the wood specimens bonded at 80 °C revealed that the water resistance of these water- and buffer-washed adhesives was significantly improved in that they exhibited no delamination during soaking compared with the meal adhesive that showed some delamination (20–30 % of the samples). Furthermore, the water resistance of these fractions with wet shear strength around 1.5 MPa was comparable to that of cottonseed protein isolate (>90 % protein) when the joints were bonded at 100 °C. The preparations from glandless cottonseed meals showed similar adhesive performances. Additional extraction of the meals with NaCl solution reduced adhesive performance. The results suggest that water- or buffer-washed cottonseed meal fractions can be used as wood adhesives and would be less costly to prepare than cottonseed protein isolates.     

Preparation and properties of corundum HCBS and ceramic concretes. Part 1. Mixed HCBS in the system electrocorundum — very fine quartz glass

The effect of the composition of original molding systems and firing temperature on the properties of fine-grained (D _max = 1.5 mm) and medium grain sized (D _max = 4.0 mm) specimens of compacted corundum ceramic concretes with a corundum-mullite matrix system are studied. Optimum properties (open porosity of 14 – 15%, ultimate strength in compression of 150 – 200 MPa) are achieved in compositions with a matrix system content of 30 – 35%. A calculation and experimental method is used to determine matrix system porosity in ceramic concrete specimens in relation to their composition.     

Functional Properties of Soy Protein Isolates Prepared from Gas-Supported Screw-Pressed Soybean Meal

White flakes (WFs) are obtained from dehulled flaked soybeans by extracting oil with hexane and flash- or downdraft-desolventizing the (defatted) flakes, and WFs are the normal feedstock used to produce soy protein ingredients. Gas-supported screw pressing (GSSP) is a new oilseed crushing technology in which traditional screw pressing is combined with injecting high-pressure CO₂, thereby producing hexane-free, low-fat, high-PDI soybean meal. The objectives of the present study were to evaluate yields, compositions, and functional properties of soy protein isolates (SPIs) produced from GSSP soybean meal and to compare these properties to those of SPIs produced from WFs. GSSP meals produced SPIs in significantly higher yields (59.7–63.1% vs. 51.6–61.1%), with greater free (0.05–0.40%) and bound fat (3.70–4.92%) contents than did WFs. There were no significant differences in protein contents of the SPI; all exceeded 90% protein content (db). SPIs prepared from GSSP meals had similar or slightly lower water-solubilities compared to SPIs prepared from WFs. SPIs prepared from GSSP meals had higher water-holding capacities and viscosities, and significantly better emulsifying and fat-binding properties compared to SPIs prepared from WFs. SPIs prepared from WFs had significantly better foaming properties compared to SPIs prepared from GSSP meals, which were attributed to the lower fat contents of SPIs prepared from WFs.     

Functional properties of soy protein fractions produced using a pilot plant-scale process

Soy proteins fractionated by the modified Nagano process (Nagano method) and a simplified pilot-plant process (CCUR method) were studied for their functional properties, including solubility, viscosity, emulsification, and foaming. The functional properties of the three fractions produced by the Nagano method—glycinin (11S), β-conglycinin (7S), and an intermediate fraction (IM)—were studied under a selected range of pH, ionic strengths, and protein concentrations. The 11S fraction was more soluble than the 7S at pH 2–3, whereas the 7S was more soluble than 11S at pH 5–6. Adding NaCl changed the solubility of both fractions at pH 4–5 compared to a neutral pH. Other functional properties were related to solubility in the 7S and 11S fractions. The CCUR method yielded only two fractions, 11S and 7S, and the functionality of those fractions was tested at a neutral pH. The solubility of the CCUR samples was slightly higher at extreme pH levels compared to 11S and 7S fractions from the Nagano method at a neutral pH. The relationship between solubility and other functional properties was clearer in CCUR samples. These results indicate that the simplified pilot-scale CCUR fractionation process can influence the functional properties of the protein fractions.     

Isopropanol fractionation of butter oil and characteristics of fractions

Fractionation of butter oil from isopropanol and characterization of the chemical composition and the melting properties of the fractions obtained have been investigated. Butter oil was fractionated from isopropanol (1∶4 wt/vol) at 15 to 30°C. The yields of stearins and oleins were dependent on the temperature employed during fractionation. Thus, 24.8 to 48.9% of stearins and 51.5 to 75.2% of oleins could be obtained as the crystallization temperature varied from 15 to 30°C. The stearin fractions displayed a distinct variation in the fatty acid compositions. The palmitic acid content of the stearin fractions varied from 39.1 to 44.0%, and that of stearic from 15.1 to 16.8%, respectively. The olein fractions contained 43.2% stearic acid, and 2.4 to 2.8% palmitoleic acid (C16∶1). The solid fat content values of the stearin fractions obtained were 62–67, 39–50, and 21–25 at 10, 20, and 30°C, respectively. From the results, it is evident that anhydrous milk fat can be fractionated at relatively high temperatures from isopropanol to produce stearin and olein fractions of specific composition and properties.     

Optimization of the Aqueous Enzymatic Extraction of Rapeseed Oil and Protein Hydrolysates

An aqueous enzymatic extraction method was developed to obtain free oil and protein hydrolysates from dehulled rapeseeds. The rapeseed slurry was treated by the chosen combination of pectinase, cellulase, and β-glucanase (4:1:1, v/v/v) at concentration of 2.5% (v/w) for 4 h. This was followed by sequential treatments consisting of alkaline extraction and an alkaline protease (Alcalase 2.4L) hydrolysis to both produce a protein hydrolysate product and demulsify the oil. Response surface methodology (RSM) was used to study and optimize the effects of the pH of the alkaline extraction (9.0, 10.0 and 11.0), the concentration of the Alcalase 2.4L (0.5, 1.0 and 1.5%, v/w), and the duration of the hydrolysis (60, 120, and 180 min). Increasing the concentration of Alcalase 2.4L and the duration of the hydrolysis time significantly increased the yields of free oil and protein hydrolysates and the degree of protein hydrolysis (DH), while the alkaline extraction pH had a significant effect only on the yield of the protein hydrolysates. Following an alkaline extraction at pH 10 for 30 min, we defined a practical optimum protocol consisting of a concentration of 1.25–1.5% Alcalase 2.4L and a hydrolysis time between 150 and 180 min. Under these conditions, the yields of free oil and protein hydrolysates were 73–76% and 80–83%, respectively. The hydrolysates consisted of approximately 96% of peptides with a MW less than 1500, of which about 81% had a MW less than 600 Da.     

Flash desolventizing defatted soybean meals washed with aqueous alcohols to yield a high-protein product

A vapor-type desolventizer was developed previously at this laboratory to recover hexane and concentrated alcohols from soybean mares. The work reported in this paper extends the application of this unit to the recovery of dilute alcohols. Soybean protein meals washed with aqueous alcohols are debittered to yield a better flavored product with a significant increase in protein content. The protein of defatted meal was increased from about 50 to 70 or 75% by washing with methanol, ethanol, or isopropyl alcohol in a concentration range of 50–70%. System modifications and critical variables were investigated so as to minimize residual alcohol and to yield a free-flowing homogeneous product. Residual alcohol in the desolventized flakes was 0.25–1.0%. Facility of removal followed the order—methanol, isopropyl alcohol, and ethanol. Two-stage flash desolventization as well as the use of the more dilute alcohols resulted in lower residual alcohol content of the desolventized product. After a minimum value for residual alcohol in the flakes is reached, further removal is difficult. However, water continues to be removed so that the alcohol water ratio becomes higher with an increased vaporization force as with increased temperature. It is postulated that the alcohol is held by adsorption or hydrogen bonding. The desolventized products analyzed: protein 72–77%; Nitrogen Solubility Index 4–16; water absorption values 328–410%. The products were light-colored, granular, and free flowing. The soybean flakes extracted with methanol exhibited the best flavor. A laboratory of the Northern Utilization Research and Development Division, U.S.D.A.     

Preparation of Diacylglycerol-Enriched Oil from Free Fatty Acids Using Lecitase Ultra-Catalyzed Esterification

Production of diacylglycerol-enriched oil by esterification of free fatty acids (FFA) with glycerol (GLY) using phospholipase A1 (Lecitase Ultra) was investigated in this work. The variables including reaction time (2–10 h), water content (2–14 wt%, FFA and GLY mass), enzyme load (10–120 U/g, FFA and GLY mass), reaction temperature (30–70 °C) and mole ratio of GLY to FFA (0.5–2.5) were studied. The optimum conditions obtained were as follows: reaction temperature 40 °C, water content 8 wt%, reaction time 6 h, molar ratio of GLY to FFA 2.0, and an enzyme load of 80 U/g. Under these conditions, the esterification efficiency (EE) of free fatty acids was 74.8%. The compositions of the FFA and acylglycerols of the upper oil layer (crude diacylglycerol) of the reaction mixture were determined using a high temperature gas chromatograph (GC). The crude diacylglycerol from the selected conditions was molecularly distilled at 170 °C evaporator temperatures to produce a diacylglycerol-enrich oil (DEO) with a purity of 83.1% and a yield of 42.7%.     

The fractionation of lanolin with urea

Summary A fractionation of lanolin was effected by contacting lanolin with urea in the presence of methyl alcohol. About 6–8% of the lanolin formed a urea adduct which, upon decomposition, yielded a hard, nontacky wax fraction. In addition to the wax fraction, a fluid fraction and a sticky semi-solid were also obtained. The latter two fractions were obtained by the solvent extraction of the nonadduct-forming material from the urea adducts. The fluid fraction, obtained in 71% yield, is a viscous liquid at room temperature. The fluid properties of the fraction can be improved by acetylation. Presented at the Fall Meeting, American Oil Chemists' Society, Chicago, Ill., October 20–22, 1958. Eastern Utilization Research and Development Division, Agricultural Research Service, United States Department of Agriculture.     

Preparation of plastic fats with zero <Emphasis Type="Italic">trans</Emphasis> FA from palm oil

A series of plastic fats containing no trans FA and having varying melting or plastic ranges, suitable for use in bakery, margarines, and for cooking purposes as vanaspati, were prepared from palm oil. The process of fractionating palm oil under different conditions by dry and solvent fractionation processes produced stearins of different yields. Melting characteristics of stearin fractions varied depending on the yield and the process. The lower-yield stearins were harder and had a wider plastic range than those of higher yields. The fractions with yields of about 35% had melting profiles similar to those of commercial vanaspati. The plastic range of palm stearins was further improved by blending them with corresponding oleins and with other vegetable oils. The plasticity or solid fat content varied depending on the proportion of stearin. Blends with higher proportions of stearins were harder than those with lower proportions. the melting profiles of some blends, especially those containing 40–60% stearin of about 25% yield and 40–60% corresponding oleins or mahua or rice bran oils, were similar to those of commercial vanaspati and bakery shortenings. These formulations did not contain any trans FA, unlike those of commercial hydrogenated fats. Thus, by fractionation and blending, plastic fats with no trans acids could be prepared for different purposes to replace hydrogenated fats, and palm oil could be utilized to the maximum extent.     

Effect of processing on the composition of sesame seed and meal

Except for a variation in the freeepsilon-amino lysine content of the protein, the Mexican screw-pressed meals were quite similar in their composition. The lysine values for sesame protein obtained for the solvent-extracted meals were much higher than those obtained for the screw-pressed meals. Screening of the endosperm and spermoderm from the solvent-extracted meals was effective in reducing the oxalate content of the resulting flour although some epiderm fragments passed through a 60-mesh screen. The decortication process completely removed the portion containing the oxalate from the seed and also reduced the calcium, sugar, and silica contents. Presented at the annual meeting, American Oil Chemists' Society, Dallas, Tex., April 4–6, 1960. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture.     

Effects of soybean pretreatments on crude oil quality

The effects of soybean pretreatments, including infrared (IR) radiation, oven toasting, microwave heating and live steam treatment on crude oil quality were investigated. Free fatty acid, oxidation value, carbonyl value and tocopherol content were used to monitor crude soybean oil quality. All soybean pretreatments were effective in improving the quality of oils from 15 and 18% moisture beans. Based on the analyses, recommended treatments are 3–4 min for IR at 220V–250W; 1 min for microwave heating at 650 W–2450 mHz; 1–1.5 min for steam heating; and 100–120°C, 30 min for oven toasting. Heat treatment of high-moisture soybeans before extraction yielded crude oil with a lower content of phosphatidic acid as compared to that of the untreated beans.