According to the study published in the journal Food Research International, neocandenatone showed “excellent integration and stability” in matrices for both gelatin gummies and hard candies.
The researchers looked at three neocandenatone samples of different purities, analyzing the genotoxicity using Ames and micronucleus tests – the first of which they said was favored by the US Food and Drug Administration (FDA). The pigment was applied to 11 gelatin gummy and ten hard candy formulations to establish its stability during storage compared to candies colored with commercial anthocyanin (E number 163) from various sources including black carrot, grape skin, purple corn, elderberry, and strawberry.
They said the pigment could be of interest to consumers due to evidence of possible antioxidant activity and in vitro cytotoxic activity against HeLa cervical cancer cells.
A hearty color
The researchers said the Mexican tree was known for its deeply pigmented heartwoods of varying colors, often used for wooden crafts, instruments and in traditional medicine. Heartwood refers to the older wood at the center of a tree, which is usually darker and harder than younger sapwood.
Pigment was extracted from dried and ground D. congestiflora heartwood using methanol.
The researchers found that: “The neocandenatone content in the wood was higher than the 2.41% and 1.37% anthocyanin content (dry matter) found in the grape skin Sousón cultivar and skins of Vaccinium ashei var. climax fruits, respectively.”
Gummy color gradient
Different shades were obtained depending on the concentration of pigment and the amount of citric acid used, with neocandenatone and enocyanin (a type of anthocyanin) producing similar colors with and without acid. In the gummy formulations neocandenatone provided a wider range of colors compared to the anthocyanins.
In the gummies a purple color was obtained with 0.014% pigment and 0.0% citric acid, red with 0.014% pigment and 1.0% citric acid. The researchers said smaller amounts of neocandenatone than enocyanin produced similar colorations, while a purple color in end product gummies not just solution was not possible with enocyanin.
Hard to crack
Anthocyanin and neocandenatone gave an equally broad range of colors in the hard candy final products. However, anthocyanin coloration varied with pH and the presence of citric acid, making it sometimes impossible to establish a correlation between acid concentration and color parameter values and therefore difficult to compare.
“In this work, it was clear that the range of colors in the candy products depended heavily on the candy matrix,” the researchers said.
“As expected, the colorations in hard candies depended on the pigment and acid concentrations. In contrast to gummies, similar neocandenatone and enocyanin concentrations must be used to achieve similar colorations in hard candies. It was not possible to obtain purple color in hard candies using any of the tested formulations.”
Crude vs. pure
The crude extract of D. congestiflora was composed of approximately 93% hydrophobic compounds, which restricted its dispersion in aqueous matrices like candy products. The researchers recommended the use of a semi-purified extract containing 71% neocandenatone since pure pigment via chromatographically was “very expensive”. However, the researchers said the crude extract could be used in fatty matrices where it could be dispersed.
Source: Food Research International
Available online ahead of print, doi: 10.1016/j.foodres.2014.03.048
“Stability in candy products of neocandenatone, a non-genotoxic purple pigment from Dalbergia congestiflora heartwood”
Authors: C. G. Gutiérrez-Zúñiga, M. Arriaga-Alba, C. Ordaz-Pichardo, P. Gutiérrez-Macías, B. E. Barragán-Huerta