Maltodextrin films

Spray Drying. Spray-dry encapsulation processes (Fig. 7) consist of spraying an intimate mixture of core and shell material into a heated chamber where rapid desolvation occurs to thereby produce microcapsules (24,25). The first step in such processes is to form a concentrated solution of the carrier or shell material in the solvent from which spray drying is to be done. Any water- or solvent-soluble film-forming shell material can, in principle, be used. Water-soluble polymers such as gum arable, modified starch, and hydrolyzed gelatin are used most often. Solutions of these shell materials at 50 wt % soHds have sufficiently low viscosities that they stiU can be atomized without difficulty. It is not unusual to blend gum arable and modified starch with maltodextrins, sucrose, or sorbitol. 

Com symp soflds are also dry products, have a smaller average size, and are comparatively sweeter (12). Both maltodextrins and com symp soflds are used to prevent caking enhance dispersibiUty and solubiUty provide body or bulk impart deskable texture bind, carry, and protect flavors control extmsion expansion provide viscosity form films and coatings provide an oxygen barrier inhibit crystallization control sweetness improve sheen improve organoleptic characteristics slow meltdown and improve freeze—thaw stabiUty. 

GA is mainly used for fat microencapsulation because it produces stable emulsions in the case of most oils in a wide pH range, and it has the ability to form films (Kenyon, 1995). Barbosa et al., 2005 studied the photostability of the microencapsulated carotenoid bixin in different edible polysaccharide. They found out that microencapsulated bixin in GA was three to four times more stable than the one microencapsulated with maltodextrin, and about ten-fold than in homogeneous solvents. 

Improved stability towards oxidation of spray dried flavor oils was achieved by using a combination of a high-maltose syrup, maltodextrin and a high molecular weight, film-forming polysaccharide, such as starch octenylsuccinate or gum ara-bic.200 201 Emulsification performance of maltodextrins is improved by treatment with octenylsuccinic anhydride and aluminum sulfate. 

Glass-Transition Temperature and Self-Detaching of Maltodextrin Films Effect of Molecular Weight and Sucrose Addition... 

Temperatures and moisture contents of dried films of maltodextrin at the moment of self-detachment from an inert solid (ordinary glass slide). 

Glass-transition curves for maltodextrins with different molecular weights (a) 4759 g/mol, DE — 04 and (b) 957.5 g/mol, DE — 19, and experimental points at the moment of self-detachment of the film from a solid surface. 

The effect of mixtures on the detachment conditions was also evaluated by dr)dng pastes made by a mixture of maltodextrin MOR-REX 1910 and sucrose, with a total solid content of 61.5%, but with increasing amount of sucrose (5, 10, and 15% sucrose, dry weight basis (dwb)). Results in Figure 21.3 indicate that for a defined drying temperature, the moisture content at the moment of self-detachment of the dried film decreased with the increase in sucrose addition. Thus the addition of sucrose made the detachment of dried films of maltodextrin from an inert solid surface during the drying process more difficult. The larger the amount of sucrose added. 

Detachment conditions of mixtures of maltodextrin MOR-REX1910 and sucrose dried film from the glass plate surface. 

In Figure 21.5, the self-detachment conditions for aqueous solutions of the maltodextrin MOR-REX 1910 and sucrose at 5, 10, and 15% (dwb) are compared with the glass-transition curves calculated using the expanded Gordon-Taylor model (Roos, 1993). The self-detachment of the dried films of aqueous solutions of the maltodextrin MOR-REX 1910 and sucrose followed the same pattern of decreasing moisture content of the material with an increase in temperature as observed with the glass-transition data. This process occurred in a temperature range of 20°C below Tg, for 5,10, and 15% sucrose concentrations, as was observed by Collares et al. (2004) for maltodextrin MOR-REX 1910 without the addition of sucrose. 

An oil-in-water emulsion was prepared from coffee aroma incorporated in coffee/vegetable oil (5%-20% w), and water-soluble coffee solids forming the aqueous continuous phase (50%-75% TS). Individual drops of emulsion (nozzle/Nj, 0.4-1 mm core of coffee oil) were sprayed on soluble coffee powder (fluid bed, pan coater), with little water content modification of powder (<4%w). The capsules were attached to the coffee powder surface (0.1%-1% w aroma), that were able to release the aroma only by dissolution in the hot water cup. The film-forming agent may be other supports such as maltodextrin, acacia gum, carbohydrates, tea, or cocoa solids, vegetables. And other flavors may be used, for example, for instant soups. 

On the other hand, the study of Kim et al. proved that the use of gum arabic, whey protein isolate/maltodextrin and poly(vilyl alcohol) as encapsulants to obtain miCToencapsulated cinnamon oil by spray drying resnlted in prolonged repellent effect against P. interpunctella (Hubner) larvae. In this case, LDPE films were coated with either inks containing the microcapsule emulsions or with PP incorporating microcapsule powders. Interestingly, the tensile properties of LDPE were not affected regardless of the method used. ... 

Chem. Descrip. Maltodextrin CAS 9050-36-6 EINECS/ELINCS 232-940-4 Uses Nutritive polymer, film-former, vise, builder, opacifier, mouthfeel enhancer for pharmaceuticals, foods, beverages, pan coatings, soup and gravy mixes nonbrowning carrier for drying sensitive prods. thickener for food systems Features Nonsweet... 

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