White flakes

Bisphenol A is a solid material in the form of white flakes, insoluble in water but soluble in alcohols. As a phenolic compound, it reacts with strong alkaline solutions. Bisphenol A is an important monomer for producing epoxy resins, polycarbonates, and polysulfones. It is produced by the condensation reaction of acetone and phenol in the presence of HCI. (See Chapter 10, p. 273)... 

In order to produce soy protein, soybeans are first dehulled, flaked, and defatted to make white flakes . Soy protein concentrates are obtained by removing a portion of the carbohydrates from defatted and dehulled soybeans. Alcohol extraction is the method most commonly used to manufacture soy protein concentrates even though it results in the loss of isoflavones. Soy protein concentrates retain most of the fiber in the original soybean and must contain at least 65% protein on a moisture-free basis to meet quality standards. The most concentrated source of soy protein is soy protein isolates (or isolated soy protein, ISP), which is required to be at least 90% protein on a moisture-free basis. It is heat-treated during processing to insure inactivation of trypsin inhibitors. Most isolated soy protein is manufactured by water extraction from defatted and dehulled soybeans and it retains the natural isoflavones. 

The crude stearone is allowed to solidify and is then broken up and dried by pressing between filter paper. The crude yield is 230-240 g. (91-95%). The product melts at 84-86° and has an acid value of zero. It is purified by dissolving in 1200 ml. of a 2 1 mixture of benzene and absolute ethanol, filtering hot, and allowing to crystallize (Note 8). After a second crystallization from the same mixed solvents, the stearone is obtained as glistening white flakes, melting clear at 89-89.5° (shrinks at 87-88°). The yield is 204-220 g. (81-87%) (Note 9). 

After the completion of the reaction, the solution was acidified to a pH of 4 with 2N sulfuric acid, followed by the addition of 50 ml of water. The solution was then extracted several times with ether. The extractant was dried over magnesium sulfate and the solvent was removed by evaporation at reduced pressure. Cold petroleum ether was then added to the resultant oily material to precipitate the product. The product was further washed with cold (10° C) petroleum ether and recrystallized several times from warm petroleum ether. The melting point of the final product was 73.5° C. Infrared spectrum of the product showed major absorption peaks relevant to the pure monomer (Figure 1). Under UV radiation, white flakes of the monomer solid turned deep blue (partial polymerization). 

Outer appearance Yellow liquid Colorless liquid White flakes White flakes... 

Stearyl alcohol comes in white flakes and is available in commercial, technical, and USP grades... 

White flakes or needles with a phenolic odor. At 40 °C, the average odor threshold concentration and the lowest concentration at which an odor was detected were 23 and 9.3 pg/L, respectively. At 25 °C, the lowest concentration at which a taste was detected was 8 pg/L (Young et al., 1996). 

White flakes orthorhombic crystals density 1.5 g/cm melts at 93°C decomposes around 200°C very soluble in water (37 g/lOOmL at 20°C) shght-ly soluble in alcohol. 

Sulphurous add is capable of forming a crystalline hydrate with water. It is procured by exposing sulphurous acid vapor with water, in a tube or other apparatus, to a low temperature, by placing this tube in a freezing mixture. Solid sulphurous acid may be procured by rapidly evaporating the liquid acid—it forms white flakes. It is heavier than the liquid, and freezes at minus 110°. It is composed of— ... 

Hydroxylamine begins to crystallize in large white flakes at 0°C. Cooling below — 10°C. seems to produce only a trivial increase in the yield. The crystals produced in this fashion are collected quickly upon a filter (Witt plate), washed with cold ether, and placed in a desiccator for 15 minutes to remove the adhering solvents. If the hydroxylamine is not to be used at once, it should be placed in a stoppered tube in an ice chest. Yield 21.0 g. (63.5 per cent of theory). 

Material Mushroom with red caps and white flakes found in birch or pine forests during rainy season in north temperate zones of eastern and western hemispheres. 

PROP Trihydrate White flakes or crystalline powder bitter taste. Mp approx 200° (decomp). Dissolves slowly in glycerin insol in chloroform, ether. 

PROP White, free-flowing powder or white flakes. D 1.20-1.21 25°/25°, fp 54-58°. 

N-Chlorosuccinimide (NCS) was purchased from Aldrich Chemical Company, Inc. and recrystallized before use according to the following procedure. NCS (25 g) was dissolved in 125 mL of glacial acetic acid at 60-65 °C in a 250-mL, Erlenmeyer flask and the resulting solution was allowed to cool to room temperature. The Erlenmeyer flask was then placed in an ice-water bath (15-20°C), and white flakes of NCS immediately precipitated and were collected by filtration on a Buchner funnel (washing with 20-mL of glacial acetic acid and then with two 20-mL portions of hexanes) and then dried at 0.5 mm for 6 hr and stored in the dark until use. 

Some plants divert part of their spent flake production away from a desolventi-zer-toaster to a flash desolventizer, which is designed to produce white flakes with high-protein solubility (PDI 70-90). White flakes are used as the starting material for producing protein isolates or concentrates, which contain >90% and 65% protein, respectively, and are used as food ingredients. 

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