Inclusion complexes of yellow bell pepper pigments with -cyclodextrin: preparation, characterisation and application as food natural colorant

BACKGROUNDThis work aimed to prepare inclusion complexes using yellow bell pepper pigments and -cyclodextrin by two different procedures (method A, ultrasonic homogenisation; method B, kneading), to characterise them and evaluate their colour stability in an isotonic beverage model. The extract/-cyclodextrin ratio was 1:2 for both inclusion methodologies evaluated. The formed extract--cyclodextrin complexes and a physical mixture of extract and -cyclodextrin were evaluated by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). RESULTSBoth methodologies resulted in good complex yield and inclusion efficiency. The colour indices L* (lightness), a* (green/red) and b* (blue/yellow) of isotonic drinks added with the complexes were measured during storage under irradiance (1400lx) and in the absence of light at temperatures between 25 and 31 degrees C for 21days. CONCLUSIONThe complex obtained by inclusion method B promoted better colour protection for the beverage compared with the use of the crude extract, showing that the molecular inclusion of yellow bell pepper carotenoids can provide good results for that purpose. (c) 2017 Society of Chemical Industry