Total and polar lipids in soybean protein meals

Soybean protein meals obtained by various oil extraction methods have different neutral oil content, and they may contain differnet amounts of polar lipids. Three soy protein meals obtained by different processing methods were extracted by two solvents consecutively, chloroform/methanol (2:1, vol/vol) and water-saturated butanol, for total lipid analysis. The organic flour (i.e., ground soybean) containted 15.52% total lipids; the high protein dispersibility index flour from extrusion-expelling processing and the white flour from conventional solvent extraction contained 11.20 and 1.84% total lipids, respectively. Organic flour contained more polar lipids than the other two protein meals on a dry-weight meal basis. Chloroform/methanol extracted most of the lipid from the meals, whereas water-saturated butanol resulted in an extract with more polar lipids than that from chloroform/methanol extraction.     

Use of sunflower (Heliantus annus, L.) in human foods. II. Enrichment of sunflower protein concentrate with fish and sesame flour

The first part of this study revealed that a sunflower meal submitted to thermic treatment resulted in a protein of better quality when supplemented with lysine, while the meal not subjected to thermic treatment, supplemented with methionine, did not increase its nutritional value. These data indicated, therefore, that the limiting amino acid in sunflower meal is lysine, and not methionine. Based on these findings, and in order to confirm previous results, fish flour (high in lysine) and sesame flour (high methionine) were used to enrich the amino acid pattern of the sunflower protein concentrate. Three diets were thus prepared at the 10% protein level, containing: Sunflower protein concentrate which provided 70% protein, plus sesame flour (30% protein). Sunflower protein concentrate with 70% protein, and fish flour (30% protein). Sunflower concentrate with 70% protein, sesame flour with 20%, and fish flour with 10% protein. These following conclusions were derived on the basis of the analysis of these results: Supplementation of sunflower concentrate with 30% sesame flour does not producer a product of high nutritional value, once again indicating that lysine and not methionine is the limiting amino acid. Supplementation of the sunflower protein concentrate with fish flour (high in lysine content) presents a protein efficiency ratio (PER), practically equal to that of the casein pattern.     

Uses of defatted and partially defatted peanut flours

Defatted peanut flour produced by direct solvent extraction and partially defatted peanut flours produced by mechanical pressing have many potential uses in foods. The defatted peanut flour has a high protein solubility and is light colored, practically tasteless, and odor free. The defatted peanut flour has been evaluated as: an additive to increase the protein content of foods such as bread and other baked goods, macaroni, pancakes, and puddings; an extender in meats such as meat loaf and frankfurters; and an aid in preparing skim and full-fat (fat added) milk-like drinks and ice creams. The characteristics of this flour also make it useful in the preparation of protein concentrates (by air classification) and protein isolates. The partially defatted flour, with about 55% oil removed, is ideal for preparing full-fat, milk like drinks and can also be used in baked goods, ice cream, meats, and so forth. This flour can also be toasted to different degrees for use in foods such as baked goods, in which a nutty flavor may be desired. The “over roasted” flour has potential for use as a cocoa diluent.     

Use of flour of pejibaye fruit (Bactris gasipaes H.B.K.) in bread making

Trial were conducted in Costa Rica in 1984 and 1985, to determine the possibility of substituting pejibaye (Bactris gasipaes H.B.K.) meal for wheat flour in bread. Utilization in three distinct mixtures was examined: 90:10, 85:15 and 80:20 percentage of wheat flour to percentage of pejibaye meal, respectively. The breads were made, and dough analyses were conducted at "Molinos de Costa Rica, S.A.", the country's principal flour mill. Chemical analyses were carried out at the University of Costa Rica. Results indicate a marked inverse relationship between both initial dough development time and dough strength maintenance, and the content of pejibaye meal present in the flour mixture. Consequent problems with sufficient dough expansion preclude utilization of this fruit meal for bread-making in proportions significantly greater than 10% of the total composite flour. The above-mentioned findings reflect the high nutritional value of the pejibaye fruit. Although the protein content is inversely correlated with the amount of pejibaye meal in the mixture, vitamin A and fat contents are positively correlated. This fact demonstrates that the utilization of pejibaye meal in bread-making may well be in some ways considered as a form of nutritional enrichment. As a final conclusion drawn from the results of analyses of the trials and sensory observations, the 90% wheat flour with 10% pejibaye meal mixture apparently was the optimum substitution level of the breads examined. The potential macroeconomic ramifications on the Costa Rican economy of producing and utilizing pejibaye meal in bread-making, are highly favorable.     

Solvent extraction of oil from soybean flour II— pilot plant and two-solvent extractions

The process of grinding soybeans to a fine flour and extracting the flour with hexane was studied on a pilot plant scale. The crude oil from the pilot plant study had 15 ppm phosphorus and was suitable for physical refining after a light acid pretreatment and bleaching. The refined oil showed a Lovibond color of 1.4 yellow and 0.3 red. The pilot plant study also showed that grinding of the soybeans and the separation of solid from miscella were the most difficult steps in solvent extraction with fine flour. A laboratory study on separation of miscella from meal by aqueous ethanol reduced the hold-up volume, but it did not remove all the miscella. A test with betacarotene showed that only the miscella outside the flour particles was displaced. Aqueous ethanol solutions used as a second solvent extracted additional nontriglyceride materials (primarily phospholipids) from the meal. Also, the free fatty acid content of the oil was increased with aqueous ethanol solution wash. The quality of the extracted crude oil was lowered by using a second solvent, but it had the advantage of needing only one centrifugation to separate miscella from meal.     

Isopropyl Alcohol Extraction of De‐hulled Yellow Mustard Flour

Vegetable oils are typically extracted with hexane; however, health and environmental concerns over its use have prompted the search for alternative solvents. Mustard oil was extracted with isopropyl alcohol (IPA) to produce an IPA‐oil miscella suitable for industrial applications. Single‐stage extraction resulted in 87.6 % oil yield at a 10:1 (v/w) IPA/flour ratio. Multiple‐stage extraction resulted in higher extraction efficiency with lower IPA use. Four‐stage cross‐current extraction at an IPA/flour ratio of 2:1 (v/w) per stage resulted in 93.7 % oil yield. At 45 °C, a 91.5 % oil yield was achieved with three‐stage extraction using a 2:1 (v/w) IPA/flour ratio. Any changes to the pH of the mixture resulted in reduced oil yield. Water also reduced the extraction efficiency. The azeotropic IPA solution containing 13 % water extracted ~40 % less oil than did dry IPA in both single and multiple‐stage extractions. Some polar compounds were also extracted, including sugars; however, protein extraction was negligible. The protein left in the extracted meal was not degraded or lost during the extraction. The results suggest that IPA is an excellent solvent for mustard oil, but water content exceeding 5 % in the solvent adversely affects the oil extraction and reuse of the IPA.     

Formulation and evaluation of the protein quality of a flour mixture of shark fillet by-products and shrimp heads

A flour proposed as a protein source for chick feeding was evaluated. The flour consisted in a 1.00:1.15 dry mixture of by-products from shark filleting (dt) and shrimp by products (cc). It had a crude protein content of 55.66%, a Ca:P ratio of 5.76 and an essential amino acid pattern similar to that of fish meal and/or shark meat. Methionine proved to be the first limiting essential amino acid. The shark meat and the by-products from shark filleting had adequate levels of available lysine (from 337 to 383 mg/g N). The flour had a fineness modulus (F.M.) of 3.95, an average particle diameter of 0.0175 inches (0.444 mm) and a uniformity index of 1:5:4 (coarse:medium:fine parts). The flour was considered suitable for chick feeding. The protein quality of the flour mixture (dt-cc) was evaluated in rats using diets which contained 3, 6, 9 and 12% protein from the product, and determining the PER, NPR and NGI values. Diets containing similar protein levels prepared from dried shark meat flour, mixed with casein, were used as standards. The flour mixture (dt-cc) had a PER of 1.60, an NGIo of 2.46, an NGI of 2.49 and an apparent digestibility of 88.80%. These values proved to be significantly (p less than 0.05) lower than those found for the corresponding shark meat flour-casein standard diets. The above results are partially explained by the high mineral content, high Ca:P ratio and high Na and K of the dt-cc mixture, factors which could interfere with the utilization of the most limiting essential amino acids and other nutrients, as some vitamins, in these diets. The Kruskal-Wallis test of the feed efficiency (EA) data obtained in growing chicks revealed that there was a significant (p less than 0.05) difference between the EA values obtained with the dried shark meat-containing diets and the standard commercial diets (Purina and a diet based on a 1.6:1.0 soybean meal:cottonseed meal mixture). No significant differences were found between the dt-cc mixture-containing diets and the commercial ones used as standard. The diet containing 6% shark meat flour was found to be the best based on the EA data. The diet with 12% of the dt-cc mixture gave similar EA values than all those containing shark meat flour; however, the greater nutritional-economic impact based on the EA data was found for the diets containing 3 and 6% of the dt-cc flour mixture.(ABSTRACT TRUNCATED AT 400 WORDS)     

Studies on the wet dehulling of sesame seed to obtain superior grade protein concentrates

Easy removal of the fibrous colored skin of sesame seed was accomplished by contacting the seed with lye solution under optimal conditions. The decuticled seed was dried mechanically and a yield of 85% on the raw material was obtained. Screw pressed or pre-press solvent extracted flour derived from the dehulled seed had an attractive white appearance, was free from bitterness and had a lower crude fibre and oxalic acid content. Both in the content of protein and its nutritional quality, the meal was found to be superior to commercial sesame cake. Heat treatment inherent to expeller operation was found to have beneficial effect on sesame protein.     

A new method of detoxification of cottonseed by means of mixed solvent extraction

For several decades, scientists in the field of vegetable oils tried unsuccessfully to detoxify cottonseed by a practical method. By using 20-30% (by wt) of ethyl alcohol (90% in vol) with commercial hexane as a mixed solvent, we were able to extract effectively both gossypol and oil from cottonseed prepressed cake or flakes. Free gossypol in meal was reduced to ca. 0.013-0.04%; total gossypol was reduced to 0.32-0.55%; residual oil was reduced to ca. 0.5% or less. Any aflatoxin present also can be eliminated by this process. The detoxified cottonseed meal can be used as animal feed. Cottonseed protein can be used to substitute for soy protein. The extracted oil is of better quality than that obtained by the usual hexane extraction method, and gossypol is a valuable byproduct.     

An Apparatus for Rapid Preparation of Oil and Oil-Free Meal from Brassica Seed

An apparatus for the rapid preparation of large numbers of oil and “oil-free” meal samples from Brassica seed is described. Batches of sixty 0.2 g to 2.0 g seed samples can be ground and solvent extracted simultaneously, followed by filtration, solvent washing and vacuum drying of the meal. The oil can be recovered quantitatively for gravimetric oil content determination.     

Adhesion Properties of Plywood Glue Containing Soybean Meal as an Extender

This study was conducted to evaluate the performance of soybean meal as a protein extender in plywood adhesive intended for sprayline coaters. Ground soybean meal, with 52.8% (dry basis, db) crude protein and 0.9% (db) residual oil, replaced the current industry extender, wheat flour, in the standard glue mix. Substitution was done on the protein content basis. Mixing and adhesion properties of the glue containing soybean meal were compared with those of the industry-standard glue. The soybean meal-based glue showed excellent mixing characteristics and its viscosity (1,275 cp) met the recommended value for this type of adhesive. Its wet tensile strength, however, was less than that of the standard glue and below the threshold value of 200 psi considered as an indicator of strong bonding. The soybean meal glue formulation was then modified further by increasing the amount of meal such that the amount of protein present was double that contributed by wheat flour in the original mix. This adjustment resulted in higher wet tensile strength (209 psi), which not only met the threshold value for strong glue bonds, but also equaled that of the standard glue. These results demonstrated that soybean meal is a viable extender in plywood glue for sprayline coaters.     

Degossypolized cottonseed flour—the liquid cyclone process

Predictions can be made safely that glanded cottonseed is likely to be with us for quite some time. Worldwide, 20 to 22 million metric tons of glanded cottonseed are produced annually. Hence a workable process for the removal of pigment glands is needed urgently if food-grade products are to be made from cottonseed. A brief history of the development of the Liquid Cyclone Process for the preparation of degossypolized cottonseed flour is outlined. Gossypol is removed in pigment glands via liquid cyclones, thus giving the development its name. The process consists of several unique operations including adequate drying of the meats prior to flaking, fluidizing of the flakes using commercial hexane, comminuting the fluidized slurry in a stone mill and adjusting the solids content of the milled slurry for proper separation of the fine flour from the glands, hulls and coarse meal in the cyclones. Finally, the flour is defatted and washed with hexane on a rotary vacuum filter, dried and desolventized under mild conditions to maintain protein quality. It is visualized that the above operations can be incorporated in a satellite plant operated in conjunction with a parent solvent extraction cottonseed oil mill. Sanitary conditions of the satellite plant will meet the exacting standards of the better food processing plants. Raw material specifications as well as type of plant needed and potential markets are discussed. One of 21 papers presented at the Symposium, “Oilseed Processors Challenged by World Protein Need,” ISF-AOCS World Congress, Chicago, September 1970. Deceased. So. Market. Nutr. Res. Div., ARS, USDA.     

Evaluation of corn germ protein as an extender in plywood adhesive

This study was conducted to evaluate the potential of wet-milled corn germ protein as an extender in plywood adhesive. Partially defatted dried corn germ from wet-milling, containing 2.1% (dry basis, db) crude oil and 24.7% (db) crude protein, was ground to 40-mesh particle size to produce the meal. The predominant water- and saline-soluble proteins were extracted from the corn germ meal (CGM) by using 0.1?M NaCl as solvent in a method that used homogenization, centrifugation, dialysis, and freeze-drying. The recovered freeze-dried protein extract (FDPE) was substituted (on protein content basis) for wheat flour in the standard adhesive mix for sprayline coaters. Adhesive containing CGM was also prepared in the same manner. Mixing and adhesion properties of the corn germ-based adhesives were compared with those of the industry standard adhesive. The adhesive containing FDPE showed dispersibility and mixing behaviors, as well as viscosity values that were almost identical to those of the industry standard and superior to those of CGM adhesive. The mean wet tensile strength of the adhesive containing FDPE was notably greater (1.71?MPa) than that of CGM-based adhesive (1.34?MPa) and wheat-based standard adhesive (1.38?MPa), which indicated stronger bonding. The results demonstrated that corn germ protein has the potential to be an alternative protein extender in plywood adhesives for sprayline coaters.     

Solvent extraction of oil from soybean flour I— extraction rate,a countercurrent extraction system,and oil quality

Measurements of rates of oil extraction from either fine flour or soybean flakes in a column showed that oil extraction from flour was dependent on the volume of solvent, but oil extraction from flakes depended on time of contact rather than volume of solvent. We interpreted the data to mean that oil was being washed out of the fine flour with little diffusion involved, whereas in flakes, the limit on rate was diffusion of the solvent into and out of the tissue. Fine full fat flour worked well in a batchwise countercurrent extraction system with mixing and centrifugal separation. Because the oil dissolved immediately and reached equilibrium rapidly, the actual material balance was close to calculated values. However, due to the large hold-up volume, the separation of miscella from the meal required several mixing and separation stages. The oil resulting from this countercurrent extraction system had a superior quality with 37 ppm phosphorus, 0.08% free fatty acids, and a light color.     

Effect of dehulling and heat processing on nutritional value of sesame proteins

Processing of edible sesame flour involves use of hot lye treatment of the seed for dehulling followed by drying, screw pressing, and solvent extraction. The effect of such processing on protein quality, especially lysine availability has been studied. The enzymatic digestibility of protein is improved as a result of dehulling, and lysine present in the flour exhibits remarkable stability to heat treatment, the maximum losses being less than 15% even under drastic conditions of heat treatment of the flour (1 kg/cm² for 60 min). Supplementation of the flour with lysine at an optimal level of 1.25 g L-lysine HCl/100 g flour enhances the nutritive value of protein, making it comparable to that of milk powder.     

Safflower meal

Safflower meal from undecorticated commercial seed is useful feed for ruminant animals. Its low energy content is a problem in poultry and swine rations. Partially decorticated meals are valuable for ruminants and are also quite suitable in poultry rations if provision is made for extra metabolizable calories, and if other feed ingredients supply additional lysine and methionine. In a properly balanced ration safflower meal produces growth rates superior to those from optimally supplemented soybean oilmeal. The flour obtained by essentially complete removal of oil and hulls is light colored, bitter, and contains about 60% protein. Debittering yields a relatively bland, 70% protein flour which has potential as a human food. Presented at the AOCS Meeting, Cincinnati, October 1965. W. Utiliz. Res. Dev. Div., ARS. USDA.     

Continuous extrusion cooking of cottonseed kernels and of partially defatted meal

Continuous extrusion cooking produces a short time pressure cooking of the material in process. The Wenger extruder-cooker has been successfully applied by others to soybeans for manufacture of full fat flour. This is a report of an investigation of the extruder-cooker applied to glanded cottonseed kernels and to partially defatted cottonseed meal. The purpose was production of cottonseed flour for human food. The principal objective in extruder processing was lowering of free gossypol to 0.12% of protein. On full fat kernels the extruder system was effective in lowering free gossypol. Most of the binding occurred in the preconditioner, and the extruder itself was relatively ineffective in binding gossypol. However the contribution of the extruder was necessary to allow free gossypol levels of 0.12% of protein to be reached. Flaked kernels cooked in this manner and then dried were successfully screwpressed. The extruder system was effective also in binding gossypol in ground, screened (through 30 mesh) meal but not in ground, unscreened meal. Presented at the AOCS Meeting, San Francisco, April 1969.     

Acidic ethanol extraction of cottonseed

Ethanol (EtOH) is being evaluated as an alternate solvent to hexane for the extraction of glanded cottonseed. Hot EtOH, needed for efficient oil and aflatoxin extraction, binds gossypol to protein. However, this binding can be minimized by acidifying aqueous EtOH with a tribasic acid, such as phosphoric or citric. While this solvent extracts oil and gossypol, it does not affect EtOH’s ability to extract aflatoxin. The defatted cottonseed meals produced from this process contained 0.03% total gossypol (which is lower than meal prepared by most other processes) and the aflatoxin content was reduced from 69 to 2.9 ppb. These are preliminary results and additional research is needed to determine commercial feasibility. The removal of essentially all gossypol from an extracted meal has the potential to expand the use of cottonseed meal as a feed, increasing its value to both the cotton farmer and the seed processor. Presented in part at the 40th Oilseed Processing Clinic, March 4, 1991, New Orleans, LA.     

Protein estimation in sesame seed and rapeseed flours and meals by a modified udy dye binding method

The Udy standard dye binding method (shaker mixing) employing Acid Orange 12 was improved through a series of single-factor experiments designed to approximate the optimum combination of sample size, mixing period, particle size, drying conditions, shaker speed, and number of glass beads added for uniform mixing. The modified procedure yielded a higher recovery of protein and had high correlations with the Kjeldahl method, i.e., 0.991, 0.995, and 0.977 for sesame flour, rapeseed meal, and rapeseed flour, respectively. Mean values obtained by the Kjeldahl and modified dye binding methods from 12–17 analyses each on single lots of sesame flour, rapeseed meal, and rapeseed flour were 58.9% vs. 59.4% 36.1% vs. 36.0%, and 60.0% vs. 59.4%, respectively. A composite analysis of cereals, legumes, and oilseeds by the modified method had a high correlation (0.995) with Kjeldahl results. Paper of the Journal Series, New Jersey Agricultural Experiment Station, New Brunswick, NJ 08903.     

Chemical composition and biological quality of defatted hazelnut flour

The results of the chemical composition and biological quality of deffated hazel nut flour are shown. The samples analyzed contained significant amounts of proteins (19%) comparable to legume flour, higher than cereals and lower than deffated oleaginous flours. The oil extracted from the seed was analyzed and the average results obtained were the following: Refraction index, 1.47; saponification No. 184.8; iodine No. 85.0. The average composition of the fatty acids obtained by gas liquid chromatography was: Palmitic acid 2.3% Palmitoleic acid 37.0% Stearic acid 0.5% Oleic acid 39.5% Linoleic acid 6.9% Linolenic acid 1.1% Eicosanoic acid 2.3% Eicosaenoic acid 4.6% Docosenoic acid 3.4% Tetraeicosanoic acid 0.3% These results indicate a good-quality oil due to the low content of linolenic acid. The nutritive value of the deffated meal measured in the rats gave a net protein ratio (NPR) of 3.58, lower than the corresponding casein value (4.10). The true protein digestibility measured in the rat gave a value of 7.3%, compared to 95% for casein. The amounts of iron and phosphorous are comparatively lower than those reported for rape-seed meal and sunflower meal.