Stability and shelf life modeling of natural colorant from bee pollen

Abstract

One of the main limitations for natural food colorants as potential replacements for synthetic alternatives is their stability and shelf life, which are determinant to their successful marketing. Bee pollen can be used as a source of natural pigments to substitute artificial colorants in the food, medicine, and cosmetics industries, showing advantages due to their bioactivity. This work studied the stability and shelf life of an oil-based carotenoid-rich extract (CRE) obtained from bee pollen via microwave-assisted extraction. Total carotenoid content (TCC), lipid oxidation indices, and color in the CIELAB space were evaluated during 90 days at three different temperatures: 30 °C, 45 °C, and 60 °C. The results showed that while the color remains stable, the TCC decreases and the peroxide index increases as a function of temperature. The overall CRE degradation kinetics was better modeled as a zero-order reaction and, with the Arrhenius equation, the shelf life of the colorant was determined as 37 months (at 20 °C) with a hue (hab) critical value of 70. These results demonstrate the high stability of a new type of natural colorant as well as the efficacy of bee pollen carotenoids in combination with oil lipids in color preservation.