Browning products

Tempeh. DehuUed cooked soybeans are inoculated with the mold, Thi pus oligosporus packed in perforated plastic bags, and allowed to ferment for 18 h. The mold mycelium overgrows the soybean cotyledons and forms a compact cake. When sHced and deep-fried in oil, a crisp and golden brown product is obtained. Although native to Indonesia, tempeh has become popular with vegetarians in the United States and other Western countries (93). 

Phenyl-4(4H)-ona-5,7-dlhydroxy-1-benzopyran (3) A mixture oi phioroglucino 1 (2 77 g 22 mnx)l) and ethyl benzoylacetate 2 (7 65 g 40 mmol) was heated lo 240 250°C l< I 5 h The cooled mixture was extracted with 5% NaOH and Ihe aqueous solution was extracted with EtaO Acidification afforded a brown product which after sublimation at 250 300°C/0 01 mm and recrystallizalion from EtOH gave 2 2 g of 3 (33 5%) mp 278°C... 

Benzaldehyde.—The aldehydes of the aromatic seiies may also be obtained by the oxidation of a methyl side-chain with chromium oxychloride. The solid brown product, C,H,.CH.)(CrO,CL)2, formed by adding C1O2CIJ to toluene, dissolved in carbon bisulphide, is decomposed with water, and benzaldehyde sepaiates out (Etard). Other methods for pie-paring aromatic aldehydes are (i) the Fiiedel-Crafts reaction, in which a mixture of carbon monoxide and hydrogen chloride aie passed into the hydrocaibon in presence of aluminium chloride and a little cuprous chloride,... 

Solochrome black (eriochrome black T). This substance is sodium 1-(1-hydroxy-2-naphthylazo)-6-nitro-2-naphthol-4-sulphonate, and has the Colour Index reference C.I. 14645. In strongly acidic solutions the dye tends to polymerise to a red-brown product, and consequently the indicator is rarely applied in titrations of solutions more acidic than pH = 6.5. 

Discussion. J. Nessler in 1856 first proposed an alkaline solution of mercury(II) iodide in potassium iodide as a reagent for the colorimetric determination of ammonia. Various modifications of the reagent have since been made. When Nessler s reagent is added to a dilute ammonium salt solution, the liberated ammonia reacts with the reagent fairly rapidly but not instantaneously to form an orange-brown product, which remains in colloidal solution, but flocculates on long standing. The colorimetric comparison must be made before flocculation occurs. 

The product was pumped in a C02 atm into a 10 liter separator, H O was recycled and the product washed with H20 in a 60 liter column with passing of C02 to an acidity of 0.001-0.005% H2S04. The earlier process without C02 yielded a dark-red to brown product of 0.03-0.05% acidity... 

As was suggested in the preceding discussion, most of the arene complexes isolated by metal-atom techniques are benzene derivatives. However, heterocyclic ligands are also known to act as 5- or 6-electron donors in transition-metal 7r-complexes (79), and it has proved possible to isolate heterocyclic complexes via the metal-atom route. Bis(2,6-di-methylpyridine)Cr(O) was prepared by cocondensation of Cr atoms with the ligand at 77 K (79). The red-brown product was isolated in only 2% yield the stoichiometry was confirmed by mass spectrometry, and the structure determined by X-ray crystal-structure analysis, which supported a sandwich formulation. 

The first product slowly reacts with atmospheric moisture to give an unidentified white product and Cd metal. At low AsFj Cd ratios a brown product, Cd4(AsF6)2. is formed ... 

Chlorogenic acid loss is also correlated with its incorporation in browning products.3 During roasting, the diphenols, 4-ethylpyrocatechol and pyrocatechol are formed from the caffeic acid moiety and the quinic acid moiety yields phenol and benzoic acid as well as all the di- and trihydroxybenzenes.39... 

Formation of Red-Brown Product in Ferricyanide/Ferrocyanide Reaction... 

The reactions of AChE-biotests results in the red-brown product (Hettchet pigment). The reaction of AChE-biotests on inhibitors can be estimated visually. The residual activity of AChE in biotests after the action of different concentrations of eserine (physostigmine) and proserine (neostigmine) is seen in Fig. 3. 

After the reaction mixture has been cooled, the excess phosphorus oxychloride is distilled under reduced pressure (80-100 mm.) (0.5-1.0 hour). Near the end of the distillation the product begins to sublime into the still head. The residual dark-brown oil is poured with stirring into an 800-ml. beaker containing 280-300 g. of crushed ice (Notes 3 and 4). The volume of the ice-water mixture is brought to 600 ml. and allowed to stand at 5° overnight. The crude light-brown product is filtered by suction and washed with water. 

The anion [Ir4(CO)nH]- is stable under a CO atmosphere (trans-effect of hydride ), whereas under nitrogen it rapidly gives brown products of higher nucleari-ty, which are not yet well-characterized9. The dianion [Ir4(CO)i0H2]2 has also been recently characterized102. ... 

Caramel means the brown products intended for colouring, not the sugary product obtained by heating sugars which is used for flavouring food such as confectionery, pastry and alcoholic drinks. 

The present procedure makes possible the preparation of large quantities of very pure 3-phenylsydnone without recrystallization. The earlier procedure produced a tan or brown product which lost its color only after several recrystallizations. Slight variations in this procedure can be used to prepare a variety of 3-substituted and 3,4-disubstituted sydnones. 

Place slides into DAB solution in Coplin jar and develop for 5-15 min under microscopic control to obtain a yellow-brown product. 

Reflectoquant A test strip containing peroxidase with an undisclosed redox indicator turns to a yeUow-brown product in the presence of H2O2, at pH 2-7. The color intensity is measured with a remission photometer . ... 

Ferric Hydroxide A fragile, reddish-brown product of iron or steel corrosion, Fe(OH)3. 

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