Dispersing hydrophobic natural colourant β-carotene in shellac particles for enhanced stability and tunable colour

Abstract

Colour is one of the most important visual attributes of food and is directly related to the perception of food quality. The interest in natural colourants, especially β-carotene that not only imparts colour but also has well-documented health benefits, has triggered the research and development of different protocols designed to entrap these hydrophobic natural molecules to improve their stability against oxidation. Here, we report a versatile microfluidic approach that uses single emulsion droplets as templates to prepare microparticles loaded with natural colourants. The solution of β-carotene and shellac in the solvent is emulsified by microfluidics into droplets. Upon solvent diffusion, β-carotene and shellac co-precipitates, forming solid microparticles of β-carotene dispersed in the shellac polymer matrix. We substantially improve the stability of β-carotene that is protected from oxidation by the polymer matrix and achieve different colour appearances by loading particles with different β-carotene concentrations. These particles demonstrate great promise for practical use in natural food colouring.

Plant-Derived Colorants for Food, Cosmetic and Textile Industries: A Review

“…For a long time, saffron has been used in food, medicine, painting and textiles. Its buffer solutions reduce cellulose oxidation [46]. Saffron has also been applied as a colorant in cosmetic products, one example being its use to dye lipstick.…”

“…Carotenoids are sensitive to light, temperature, pH and redox agents. An effective method to improve their properties is to microencapsulate carotenoids like β-carotene, which extends its shelf life and modifies the color [46]. In one study, β-carotene was uniformly dispersed in a shellac polymer matrix to prevent its degradation over time.…”

“…Moreover, adding antioxidants like caffeine or propyl gallate improved β-carotene stability. Shellac particles have the ability to implement various hydrophobic colorants, therefore this process can be useful in natural coloring in industrial applications [46]. It has the potential to be applied in cosmetic products as well.…”

Fate of β-Carotene within Loaded Delivery Systems in Food: State of Knowledge

“…The encapsulation of β-carotene in micro-/nanosphere was first carried out with a carrageenan/carboxymethyl cellulose-based microsphere to determine the release kinetics of encapsulated β-carotene from genipin-cross-linked kappa-carrageenan/carboxymethyl cellulose [ 153 ]. During course of time, several studies were carried out to evaluate the potential of polymeric micro-/nanospheresas an alternative delivery system for β-carotene encapsulation [ 188 , 191 , 192 , 193 , 194 , 195 , 196 , 197 , 252 ]. Nevertheless, there is a scarcity of data on the use of nano-/microsphere for the purpose of β-carotene fortification in food systems.…”

Fate of β-Carotene within Loaded Delivery Systems in Food: State of Knowledge

“…The encapsulation of β-carotene in micro-/nanosphere was first carried out with a carrageenan/carboxymethyl cellulose based microsphere to determine the release kinetics of encapsulated β-carotene from genipin-cross-linked kappa-carrageenan/carboxymethyl cellulose [122]. During course of time, several studies were carried to evaluate the potential of polymeric micro-/nanospheres as an alternative delivery system for β-carotene encapsulation [119,[123][124][125][126][127][128][129][130]. Nevertheless, there is a scarcity of data on the use of nano-/microsphere for the purpose of βcarotene fortification in food systems.…”