Defatted soy flour

Use of some oilseed proteins in foods is limited by flavor, color, and flatus effects. Raw soybeans, for example, taste grassy, beany, and bitter. Even after processing, residues of these flavors may limit the amounts of soybean proteins that can be added to a given food (87). The use of cottonseed and sunflower seed flours is restricted by the color imparted by gossypol and phenoHc acids, respectively. Flatus production by defatted soy flours has been attributed to raffinose and stachyose, which are removed by processing the flours into concentrates and isolates (88). 

Defatted soy flour was suspended in water to 8% (v/w) protein, pH was adjusted to 6 by HCl before 640 mg/L Novozyme 415 (a-galactosidase), 10 mg/L Phytase L (Novo Nordisk) and 53 mg enzyme protein/L rhamnogalacturonase B were added. After 4 hours at 50 C the pH was adjusted to 8 by NaOH, and the slurry was centrifuged. The supernatant was pasteurized (85°C, 5 minutes) and freezedried. Protein was measured as 6.25 x Kjeldahl N. Phytate was measured as described in [16], and dietary fibres were analysed as described in [17]. 

Figure 2. Relationship between calcium solubility and pH after complete digestion for four soy products. Key solid line, full-fat soy flour long-dashed line, soy protein isolate short-dashed line, soy protein concentrate and dotted line, defatted soy flour...

Note The substrate was a commercial defatted soy flour product. 

Advances in soy protein processing technology have allowed extensive diversification of protein product applications. More sophisticated soy protein products now manufactured have more functionality, better performance, more consistency and better flavor than commercially available defatted soy flour and grits (50% protein dry basis). Among these products are improved textured soy flours, concentrates, and isolates (50%, 70% and 90% protein dry basis, respectfully), functional and non-functional soy protein concentrates (70% protein dry basis) and highly soluble, highly functional isolated soy proteins (90% protein dry basis) (6-8 14-18). 

The addition of sugar required a different formulation for MCSM from the proportions stipulated by the commodity specification (11). Also, in lieu of the usual procedure of mixing commodities in a given proportion to formulate corn-soy-milk, protein and fat percentage levels of MCSM were set identically to those specified for CC. Cornmeal, defatted soy flour and soy oil proportions were then adjusted by computer to meet these constraints. The vitamin premix provided the antioxidants B.H.A. and B.H.T., each at a level of 0.0022 percent (11) in both blends. 

Ingredients most commonly used in textured vegetable protein products are defatted soy flours or grits. Preferably, the defatted soy flour should contain a minimum of 50% protein with a nitrogen solubility index of 50 to 70, a maximum of 30% insoluble carbohydrate, and less than 1% fat (9). ... 

Preparation of Raw Materials. Defatted soy flours used in this study were Soya Fluff-200W (Central Soya Inc., Fort Wayne, IN) and Extra Acted Soy Flour 200-1 (A.E. Staley, Decatur, IL). These two flours met the requirements proposed by Smith (9 ). ... 

In this Hand Press study all raw ingredients were processed under the conditions optimized for defatted soy flour temperature (143 C-160 C) pressure, 250-300 psi and retention time,... 

EXTENDER. A low-graxily material used in paint, ink. plastic, and rubber formulations chiefly to reduce cost per unit volume by increasing bulk, Extenders include dialomaccou.s earth, wood flock, mineral rubber, liquid asphalt, etc. Microscopic droplets of water fixed permanently in a plastic matrix are an efficient extender tor polyester resins. In the food industry, the term refers to certain extruded proteins, especially those derived from soybeans, which are used in meat products to provide equivalent nutrient values at lower cost. Made from defatted soy flour, they are often called textured proteins. 

Ingredients. All ingredients were obtained commercially along with compositional information and consisted of corn starch (National Starch, Bridgewater, NJ), whey protein concentrate (WPC) and sodium caseinate (SC) (Leprino Foods, Denver, CO), defatted soy flour (DSF) (Archer Daniels Midland, Decatur, IL), soy protein concentrate (SPC) (Central Soya Company, Fort Wayne, IN), and gluten (G) (Ogilvie Mills Ltd., Montreal, Canada). 

Whole Body Retention of 52inc from Defatted Soy Flour, Acid... 

Effect of Calcium and Magnesium on In Vitro Bioavailability of Zinc from Defatted Soy Flour ... 

In vitro tests using other procedures (19) were carried out in our laboratory (Ketelsen et al., manuscript in prep.) to study the dialyzability of zinc from slurries of defatted soy flours over a range of pH s. Either 2inc was added to soy slurries as zinc carbonate (extrinsic label) or the zinc was intrinsically labeled in soybeans grown hydroponically. Results from these studies (data not shown) indicated that the extrinsic and intrinsic zinc pools do not completely mix. The results showed that the pH of the soy suspensions affected the quantity of zinc that was bound in complexes of molecular weight in excess of 12,000. Also, intrinsic zinc was more likely to be bound to high molecular weight complexes than extrinsic zinc, especially for slurries at pH 3. 

A flow sheet for making partially defatted soy flour is shown in Figure 10. Food-grade soybeans are cleaned, cracked and dehulled, and extruded by a dry extruder to free the oil. The oil is then removed by a screw-press. The press-cake is ground and adjusted to 21% moisture content and is formed... 

Eldridge (1982a) determined isoflavones in defatted soy flour, protein concentrate and isolate, and found that the total isoflavone decreased from defatted flour to... 

Adding antioxidants to the defatted soy flour prior to alkaline extraction enhances the solubility of the protein isolate in proportion to the decrease in oxidation of thiol groups (Boatright and Hettiarachchy, 1995). 

TVP (textured vegetable protein) - Made from defatted soy flour that has been compressed and processed into granules or chunks. When rehydrated, TVP has a texture similar to ground beef and can be used as a low-fat replacement for beef. (The fast food industry has used TVP for years as a meat extender because of its low cost.)... 

The first soybean protein ingredients made commercially available for food use included full-fat and defatted soy flours and grits (3, 7, 8). These products contain ca. 46-59% protein (NX 6.25) on a moisture-free basis and are available with various heat treatments for specific end-use. Soy protein concentrates and soy protein isolates were introduced into the market about 15 years ago (3, 9, 10, II). By definition soy protein concentrates must contain no less than 70% protein (N X 6.25) and isolates no less than 90% protein (N X 6.25), all on a moisure-free basis. In the past several years there has been much activity in the commercialization of textured soy protein products intended for the extension and replacement of meat. These textured products may be obtained through fiber spinning, shred formation, extrusion, or compaction (12, 13, 14, 15). In addition, soybean milk solids and the heterogeneous proteins in soybean whey might serve as useful substrates in chemical modifications for food use. This short recitation of commercial products illustrates the type of crude protein fractions available for practical modification. Many useful functional properties have been ascribed to these new food proteins. 

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