Intercalação de corantes alimentícios em hidroxissal lamelar de zinco para aplicação em cupcakes

Abstract

To obtain a food additive with better quality to factors such as heating, light and degradation, the intercalation of the food dyes, tartrazine yellow (AT), Bordeaux red (VB) and brilliant blue (AB) into a zinc layered hydroxysalt (HSL) was performed using co-precipitation method. After that, the intercalation products were applied in cupcakes formulations. The cupcakes are the most consumed bakery products in the world by different age groups and social classes, being associated by the population as a delicious product and with particular sensory. The intercalation in the products, HSL/AT and HSL/VB was confirmed by X-ray diffractometry (XRD), since it was observed at a basal distance of 31,59 Å and 17,6 Å, respectively. For the HSL/AB compound, the basal distance value didn’t correspond to the intercalation of AB into the layered matrix. This fact may have occurred due to the size in the molecule of the brilliant blue as a result of steric cobbling. By vibrational spectroscopy in the infrared region (FTIR), the spectra show characteristic bands of the pure dyes and the hydroxysalt. Furthermore, from the thermal analyses (TGA/DSC) there was an improvement in thermal stability and also the general formulas of the intercalation compounds were estimated, Zn5(OH)8(NO3)1.28(tartrazine yellow)0.72. 3.72 H2O with molar mass 960.64.g.mol-1, to HSL/AT compound, and Zn5(OH)8(NO3)1.81(bordeaux red)0.19.3.25H2O with molar mass 739.826 g.mol-1, to HSL/VB. When the intercalation compounds were applied to cupcakes and the color was evaluated for 15 days, it was observed that HSL/VB produced an internal and external red color close to the precursor VB, and HSL/AT produced a more stable yellow color, with smaller variations for the yellow component after 15 days. HSL/AT was found to be selective for the yellow color and showed good stability. These data corroborate that the intercalation of the AT and VB dyes into a layered matrix was effective as confirmed by XRD, FTIR and TGA/DSC analyses.