Starch oxidised starches

Oxidised Starches. The effect of oxidation is to diminish the tendency to form micelles, which in turn reduces the tendency to gel, as well as making the paste more stable. The usual oxidising agent is hypochlorite. 

E 1103 Invertase E 1105 Lysozyme E 1200 Polydextrose E 1201 Polyvinylpyrrolidone E 1202 Polyvinylpolypyrrolidone E 1404 Oxidised starch E 1410 Monostarch phosphate E 1412 Distarch phosphate E 1413 Phosphated distarch phosphate E 1414 Acetylated distarch phosphate E 1420 Acetylated starch E 1422 Acetylated distarch adipate E 1440 Hydroxy propyl starch E 1442 Hydroxy propyl distarch phosphate E 1450 Starch sodium octenyl succinate E 1451 Acetylated oxidised starch E 1505 Triethyl citrate E 1518 Glyceryl triacetate (triacetin)... 

Starch utilization in plastic and rubber compositions began in the 60s and 70s, with oxidised starch in rubber and other polymers, such as urethane foams, poly(vinyl alcohol) and copolymers of poly(ethylene-co-acrylic acid) formulations, and as a filler in plasticized polyvinyl chloride (PVC) [37,39]. In another technique, gelatinized starch was mixed with PVC latex and the water was removed to give a PVC-starch composition, which was mixed with a PVC plasticizer such as dioctyl phthalate (DOP). 

Size press starch may be non-ionic, from in-mill enzymatic conversion or thermo-chemical conversion of native starch. It may be anionie if an oxidised starch is used. (Note this refers to chemically modified oxidised starch. Many American texts wrongly refer to any viscosity-reduced starch - including enzyme-converted and thermo-chetnically converted stareh - as oxidised stareh. Such processes do not form any carboxyl or carbonyl groups on the starch.) Furthermore, cationic and amphoteric starches are frequently tpplied on multi-purpose office paper for improved ink-jet printability. 

Oxidised starch E 1404 Confectionery, dairy products, batters and breadings, coatings... 

Several transition metal catalysts based on Fe, Cu or W salts (0.01 -0.1 mol%) have been proposed to activate H2O2 which is a well suited oxidant from an environmental and economical point of view. However, the concentration of metal ions was quite high and because oxidised starch has good complexing properties heavy metals were retained by carboxyl functions in the modified starch. 

Non-gelling Starches. These products are intended for uses where the starch replaces a gum like gum acacia. A typical product for this use might be an oxidised waxy maize starch. 

Starch-Iodide Paper.—Used as an indicator for nitrous acid, and for halogens and other oxidising agents. Turned bluish-violet by a trace of oxidising agent and brown by excess. 

There is a very simple and quick method that can be used to detect the reducing power of sulphur dioxide, developed in the last century and often called the Ripper titration (Ough, 1988). In this method, sulphur dioxide is titrated against iodine or potassium iodate/potassium iodide solution in the presence of starch. When all the sulphur dioxide has been oxidised, a blue colour is produced by the reaction of free iodine with the starch. This is a very quick method but will give only an estimate of the level of sulphur dioxide as other reducing substances, such as ascorbic acid, will interfere consequently, this method is not particularly appropriate for juices with high ascorbate levels. 

Procedure. The volume of iodine solution (1) required to oxidise the free sulphurous addin 10 c.c. of the wine is first approximately determined, starch paste being used as indicator if the wine is red and highly coloured, it should be suitably diluted. In a flask arranged as for the preceding determination a), 100 c.c. of the wine, 2 c.c. of concentrated hydrochloric acid and the necessary amount of the iodine solution are placed. After some minutes sodium arsenite solution is added in amount corresponding with the iodine solution used and hence capable of destroying the whole of the iodine added. 

Rubber is vulcanised by treatment with sulphur chloride or by heating with sulphur. In most cases, however, rubber articles are made, not of pure vulcanised rubber, but of the latter mixed with various other substances, organic and inorganic. The organic substances more commonly used are brown and white factis, fatty oils, oxidised oils, waxes, mineral oils, paraffin wax or ceresine, resin or resin oils, bitumens, tar, pitch, starch, and artificial dyes. Very many inorganic compounds may be added either as fillers or to give colour, e.g., talc, kaolin, asbestos, chalk, gypsum, lime. 

The oxidising properties of ozone have led to the application of this gas to the bleaching of such substances as starch, flour, oils, and wax, delicate fabrics, etc. It has been used in the production of artificial silk and synthetic camphor. It has also been used to aid the ageing or maturing of wines, spirits, and tobacco. The action of ozone on unsaturated organic compounds provides a very convenient general method for the preparation of aldehydes and ketones, which has already been applied to the manufacture of vanillin for flavouring purposes and heliotropin for perfumery. 

Cloez (Compt. rend., 1856, 43, 38 1861, 52, 527) found that starch iodide papers are coloured by the exhalations of certain trees indicating the presence of some oxidiser, though not necessarily of ozone. 

This sample should be examined visually for colour and the presence of tablet residues or excipients (often maize starch). The odour should be noted as tiiis may indicate the presence of alcohols, aldehydes, ketones, phenols, cyanide, ethchlorvynol, nicotine, etc. The following tests, details of which are given on p. 5, should be performed Trinder s test for salicylates, cresol-ammonia test for paracetamol, FPN reagent for phenothiazines, Fujiwara test for trichloro-compounds, and the diphenyl- nine test for oxidising agents. In addition, tiie Reinsch Test for heavy metals (p. 57) should be carried out, and a diluted, filtered extract examined by direct ultraviolet spectrophotometry for drugs with highyl values. 

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