Dextrin solution

Either the Mohr titration or the adsorption indicator method may be used for the determination of chlorides in neutral solution by titration with standard 0.1M silver nitrate. If the solution is acid, neutralisation may be effected with chloride-free calcium carbonate, sodium tetraborate, or sodium hydrogencarbonate. Mineral acid may also be removed by neutralising most ofthe acid with ammonia solution and then adding an excess of ammonium acetate. Titration of the neutral solution, prepared with calcium carbonate, by the adsorption indicator method is rendered easier by the addition of 5 mL of 2 per cent dextrin solution this offsets the coagulating effect of the calcium ion. If the solution is basic, it may be neutralised with chloride-free nitric acid, using phenolphthalein as indicator. 

The thermostable CGTase produced by Jhermoanaerobacter sp. ATCC 53,627 is able to liquefy starch at pH 4.5 under standard industrial conditions. It is, therefore, unnecessary to pH adjust the dextrin solution prior to saccharification as is normally done in the industry today. Since there is no need for pH adjustment, significant process advantages are realiz. There is a substantial cost improvement with regard to chemicals, ion-exchange media, charcoal, etc. Also, unwanted by-product formation e.g., maltulose, colored products, base-catalyzed products are reduced. Consequently, these advantages will translate into real savings to the starch industry. 

Preparation of Anhydrous Chromium(III) Chloride. Perform the experiment in a fume cupboard Grind 5 g of charcoal into a fine powder in a mortar, mix it with 12.5 g of chromium(III) oxide, add a thick starch size or a dextrin solution in cold water, and make beads about 5 mm in diameter from the mixture. Put the beads onto a clay dish and dry them in a drying cabinet at 110-120 °C. Next put them into an iron crucible, cover them with the charcoal powder and a lid, and roast them. 

Clarity and Color of Solution A 1 10 aqueous solution is colorless and has no more turbidity than a standard mixture prepared as follows Dilute 0.2 mL of Standard Chloride Solution (see Chloride and Sulfate Limit Tests, Appendix IIIB) with water to 20 mL add 1 mL of 1 3 nitric acid, 0.2 mL of a 1 50 dextrin solution, and 1 mL of a 1 50 silver nitrate solution mix and allow to stand for 15 min. 

To Damp Stars.—Stars containing nitrate of strontium must be damped either with lac solution or wax solution anything containing water destroys the color. Niter stars may be damped with gum water, dextrine solution or thin starch. Most other stars with either of the solutions. Crimsons and greens wilt mix with boiled linseed oih but they cannot then be matched, as oil renders meal powder almost imfiammable. With all stars, not a drop more of the solution should be used than is sufficient... 

To l oz. add 24 drops of boiled linseed oil rub them thoroughly together in a mortar then spread out too mixture for a few days to dry. When dry, mix with starch, dextrine solution or gum water, and chop into % or in. cubical blocks. They will keep for years, and improve by age. in order that a star may tall, it must rapidly burn through and leave a ein-deo, or scoria from this, as it falls, minute portions become detached, and trail behind. 

The cohesive power of glutinous rice starch is very strong this is seen clearly by comparing this starch with others like dextrine. Add ten times as much water to glutinous rice starch and stir well. Test it between the fingers, and it is clear how far more cohesive it is than a dextrine solution which is prepared in the same way. 

A common observation, which constitutes a practical nuisance in the laboratory, is the growth of molds on unprotected " Schardinger dextrin solutions hence certain molds at least must have the enzymic machinery for converting Schardinger dextrins into more conventional energy sources. 

Dextrinated lead azide, Dextrinated lead azide is made by adding, over a period of 30 min at 60 C. a dilute (3%) sodium azide to an equal volume of a lead acetate solution (7%) which contains dextrin from potato starch in a quantity of 6% to the expected yield of 6% of lead azide. The dextrin solution is made sliglitly alkaline with sodium hydroxide. The product contains ca. 92% of lead azide. 

In the preparation of dextrin solutions, the dextrin was stirred into about 1500 ml of boiling, deionized water, allowed to cool overnight, filtered, and the filtrate made up to 2000 ml at 20°C with water. The three solutions for batches 1, 2, and 3 were each prepared from 100.24 g of the Dextrine, White Farina, to yield solutions of 45 g dextrin per 1000 ml. The solution for batch 4 had a concentration of 45 g/1000 ml, prepared from 100.45 g ofMomingstar dextrin. For batch 5 the solution concentration was 18 g/1000 ml and was prepared from 41.80 g of the Momingstar dextrin. 

The dextrin is isolated from an enzymolysate of a 5% starch paste incubated for 5 to 7 days with macerans amylase. The enzymolysis is carried out in the presence of a precipitant such as toluene for precipitating the cyclic dextrin and an inhibitor such as thymol for inhibiting bacterial contamination. At the end of the enzymolysis period, the complex of -dextrin and toluene is collected by centrifugation in a Sharpies centrifuge and boiled in water to remove the toluene. The concentration of solids is adjusted to 20%. The -dextrin solution is heated to dissolve the dextrin, filtered to remove insoluble material and allowed to cool to room temperature. Large crystals of -dextrin are formed and these are collected on a filter and air dried. 

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