Starch derivatives oxidation

Viability of Starch Derivatives as Flavoring Encapsulants. The capillary GC vapor phase flux term (defined by a percent external standard or ZEStD flux) previously described (34) was used to screen starch derivatives (oxidized, dextrinized and/or covalent amino acid linkage) as to their flavor encapsulation potential. The samples were prepared as previously described (34) with the exception of an added reduced pressure deaeration step, thus allowing the use of the headspace diffusivity versus retention standard curves to predict volatile lemon oil retention following spray drying. 

Starch Oxidation. In order to produce starch derivatives with improved water dispersibilities and reduced retrogradation potential two oxidative reagents were tested sodium hypoch-... 

Starch (amylose and amylopectin) hydrolysis along with ester-fication, etherification or oxidation have been previously discussed as available methods for producing starch derivatives with improved water dispersibilities and reduced retrogradation potential (, ). Since oxidative and hydrolytic reactions are simple, easily controlled chemical modifications, starch-derived polymers made by hydrolysis alone or oxidative and hydrolytic processes were developed and tested. 

Among enzyme modified starch derivatives,cyclo dextrins behave as empty molecular capsules with the ability to entrap guest molecules of appropriate geometry and polarity.The included molecules are protected from surroundings light, heat,oxidation, etc. The flavor cyclodextrin com -plexes show the above advantageous properties while they are in the dry,solld state.On contact with water,cyclodextrin complexes release their flavor content. In Hungary,the spice flavor beta-cyclodextrin complexes have been on the market, since 1982. 

In aqueous alkaline solution or in acetic acid, potassium permanganate is a nonspecific oxidant that has been used in the preparation of uronic acids and derivatives. Thus, good yields of D-galacturonic acid (35) may be obtained by oxidation of 1,2 3,4-di-(3-isopropylidene-a-D-galactopyra-nose.154 D-Glucuronic acid (34) can be prepared from starch by oxidation... 

Derivation Oxidation of cane sugar, glucose, starch by nitric acid. 

Oxidation products from starch are also available indirectly. For example, Horton and coworkers485-487 prepared 6-aldehydo amylose and starch derivatives by photolysis of 6-azido-6-deoxy derivatives. The oxidation pattern of starches can be determined by hydrolysis of the reaction product and subsequent identification of the components of such hydrolyzates as their trimethylsilyl derivatives 488... 

Oxidation of various starch derivatives has generally been performed empirically to control the functional properties of products, and in general, the structures of such products have not been characterized. 

Graft copolymers were also produced by bubbling alkylene oxides through starch solutions in dimethyl sulfoxide in the presence of potassium naphthenate.2888,2889 Another approach involved grafting polyethylene oxide) to starch. Polyethylene oxide) was converted into a chloroformate derivative and subjected to a reaction with starch alkoxide 2890 Poly(alkylene glycol) could be grafted onto starch by means of cyclic aliphatic acid anhydride in the presence of 4-toluenesulfonic acid 2891 The products were water soluble. 

One-step chemical or biochemical modification of naturally produced structures under (1). Above examples are cellulose and starch derivatives, glucose and fructose, glycerol, fatly adds, ethanol, dtric add, glutamic and lactic add by fermentation, lactulose, lactitol, and lactobionic add by isomerization, hydrogenation, and oxidation, respectively, from ladose. Mother Nature offers definitely a variety of fine starting materials for spedahty chemicals. 

Polymer Blends Incorporating PHA. The mechanical properties, morphology, biodegradability, and thermal and crystallization behavior of PHAs melt-blended or solvent-cast with nonbiodegradable pol5uners [such as poly(vinyl acetate)] and with biodegradable materials [such as wood cellulose fibers (21) and starch] have been reviewed (22). PHB blends with poly(ethylene oxide), poly(vinyl alcohol), poly (L-lactide), poly(D,L-lactide), poly( -caprolactone), poly(3-butyrolactone), P(HB-co-HV), and cellulose and starch derivatives have been... 

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