Starch decanal

An example for such a reaction with decanal as ligand and potato starch as complexing compound is discussed in the following ... 

The formation of decanal - starch - complexes with time at different temperatures is presented in Figure 1. The reaction is completed in a matter of minutes, and a stable equilibrium is obtained. Isotherms of complex formation are shown in Figure 2. The complex formation starts at very low concentrations and comprises appreciable amounts of ligand. We are actually studying these reactions in some detail and are interested in the consequences of these interactions for taste and odor perception. As reported elsewhere, the complexed ligands, if present in dry state, have a remarkably increased chemical stability (25). 

Figure 1. Formation of decanal—starch complexes with time—starch (as glucose) 0.613mM decanal 5.31 M H20 10 mL pH 7.0 temperature 20, 35, 50°C...

Binding parameters and X-ray diffraction patterns of the complex of starch with 1-decanal do not differ significantly from corresponding analyses performed using 1-decanol.656,679 The temperatures of formation of the aldehyde complexes are likewise close to those for relevant starch-alcohol complexes.673,680 Analysis of the binding sites of the complex suggests that both amylose and amylopectin are involved in complexation, but these complexes are rather weak.717... 

Fig. 5.6 The formation of inclusion complexes ofpotatoe starch with decanal and menthone under isothermal conditions [16]...

After partial hydrolysis the starches lose a major part of their flavour binding properties. Examples of partially hydrolyzed starch products are dextrins (acid or enzymatic hydrolysis) and maltodextrins (generally enzymatically hydrolized). Acetaldehyde, ethanol, decanal and limonene only bind weakly to dextrins (presumably by adsorption) [22[, while ethylacetate is not adsorbed at all [1[. In the same way, alcohols (such as ethanol, propanol, butanol, pentanol and hexanol) and menthol are only weakly adsorbed on maltodextrins [11, 23]. 

Entrapment of luciferase from Photobacterium leiognathi in starch gels increases it s K , for dodecanal and tetradecanal to 1/3, but the change is insignificant for decanal. Also, K of aldehydes with different chain length is smaller for immobilized luciferase than for the soluble enzyme. ... 

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