Distribution of oil solubilized β-carotene in stabilized locust bean gum powders for the delivery of orange colorant to food products

Abstract

Galactomannan gum (locust bean gum; LBG) was used to distribute and stabilize vibrantly orange colored oil-solubilized β-carotene (βC) into dry food powders. Powders were prepared by homogenization of oil solubilized βC into hydrated LBG, followed by addition of stabilizers (lecithin, soy protein hydrolysate, and α-tocopherol), freeze drying, and course grinding. This produced dry and light powders that display mild adherance to the skin and show no color or phase separation. ATR-IR spectra indicate the mannan powders create a highly dispersed lipophilic phase. Color stability testing showed LBG-only powders had short-term thermal stability (1 h at 80 °C) but little effect against UV exposure and storage. Incorporation of lecithin and soy protein hydrolysate both enhanced the orange color stability against UV-a exposure and inclusion of α-tocopherol resulted in full protection through the thermal, UV-a, UV-c, and storage. Formulation of similar powders inclusive of food flavorings may be of interest to industries targeting synthetic colorant replacement.