Maltose dehydration

Symps of 25—30 DE are used as spray-drying aids in products such as coffee. High conversion symp, maltose symp, and 42-DE symp are used in jams and jeUies. Com symp is also used in table symps, baby food, meat packing, breakfast foods, salad dressing, pickles, dehydrated powdered foods, medicinal symps, textile flirnishings, adhesives, and numerous other products and processes. 

FIG. 10 Vitamin C loss (percentage of apricot content before drying) and browning index (BI) of apricot cubes air dried (NT) or air dried following 60-min osmotic dehydration at 25 °C at atmospheric pressure in 60% (w/w) sucrose (SU) or maltose (MA) or 13% (w/w) sucrose (ISO) solution added with 1% ascorbic acid and 0.5% NaCl (Camacho et al., 1998). All samples were dried at 60 °C up to aw = 0.80. 

The dehydration of the enediols is a reaction subject to general acid-base catalysis. The deoxyaldosulose 7a has been isolated from 3-O-benzyl-D-glucose34 and from D-fructose35 after treatment with alkali, and from D-fructose35 and various Amadori products8 after treatment with acid. The most successful preparation of 7a has been by way of amine addition compounds an improved procedure has been reported.36 Compound 9a has been isolated as a product of the alkaline treatment of both cellobiose37 and maltose.38 The isolation of 10a has not been reported, but it has been synthetically39 prepared. 

Complexes of maltose with urea, thiourea, imidazole, methanol, 2-oxazolidinone, N,N-dimethylformamide, and hexamethylphosphoric triamide have been described.131 These complexes were noncrystalline and hygroscopic. Such complex-forming reactions could be valuable in the preservation of food flavors during the dehydration process. Sugars have been shown to complex with ethylenediamine.133,133 The nature of the complex has been suggested to be that of a proton-transfer type, in which the carbohydrate moiety is the proton donor and the amine is the proton acceptor. 

Freeze-dried liposomes loaded with doxorubicin (DXR) have been stored for 6 months at temperatures between -20 and +50 °C. Up to 30 °C, no sign of degradation was found, but at 40-50 °C, well below the Tg of the dried cake, the total DXR content and the retention of the drag after dehydration decreased, whereas the size of the liposomes increased to a certain extent. The stability with RM below 1% was better than with RM 2.5-3.5%. Lactose, trehalose and maltose have similar lyoprotectant properties, whereas liposomes with sucrose showed an increase in size. 

Concentrations and types of sugars or oligosaccharides also affect the viscosity of pectin solutions. Chen and Joslyn (1967) and Kar and Arslan (1999a) found that sucrose, dextrose and maltose increased the viscosity of aqueous pectin solutions whereas dextrins reduced it. The viscosity-enhancing effect of the sugars was interpreted in terms of the decrease in dielectric constant of the solvent, dehydration action and hydrogen bonding formation. However, the effect of dextrins on the viscosity of pectin was apparently an artifact due to ionic impurities in the dextrin. 

Mixtures of osmoactive substances are also used. Maltini et al. [116] used sucrose and starch syrup in a ratio of 1 1. Lerici et al. [117] dehydrated apples in a solution containing 42% fructose, 52% sucrose, 3% maltose, 3% polysaccharides, and 0.5% sodium chloride in dry matter. Mastrocola et al. [118] used solutions containing sucrose and fructose... 

FIGURE 45.10 Droplet temperature T and thermal degradation Aj. in maltose-water system vs. reduced time t/R for two air temperatures (1) to 100°C, and (2) to 80°C. (From Kerkhof, P.J.A.M. and Schoeber, W.J.A.H., Theoretical modeling of the drying behavior of droplets in spray dryers, in Advances in Preconcentration and Dehydration of Foods, A. Spicer (Ed.), Elsevier Applied Science, London, U.K., pp. 349-397, 1974. With permission.)... 

A disaccharide is composed of two monosaccharides linked together. The most common disaccharides are maltose, lactose, and sucrose. When two monosaccharides combine in a dehydration reaction, the product is a disaccharide. The reaction occurs between the hydroxyl group on carbon 1 and one of the hydroxyl groups on a second monosaccharide. 

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