Optimising the Eco‐Friendly Extraction of Carotenoids From Gac Fruit: A Sustainable Solution for Natural Red Food Colourants

ABSTRACT Plant‐based red food colours encounter significant challenges regarding pH sensitivity, off‐flavours, processing instability and reduced vibrancy compared to synthetic dyes. These issues, along with high costs and inconsistent supply, highlight the urgent need for alternative sources, stabilisation technologies and scalable production. Gac fruit ( Momordica cochinchinensis Spreng) is one of the rich natural sources of red‐hued carotenoids. This study was conducted with an objective to come up with an efficient, low‐cost and eco‐friendly method for carotenoid pigment extraction from gac fruit with the perspective of food application. Among the different methods, the extraction method using ethyl lactate showed the highest concentrations of total carotenoids (2069.83 ± 4.38 μg/g), β‐carotene (689.43 ± 1.04 μg/g), lycopene (1052.31 ± 0.87 μg/g) and lutein (216.96 ± 0.22 μg/g). The pigment concentrate obtained using ethyl lactate solvent exhibited superior instrumental colour values: L* (60.44 ± 0.12), a* (61.35 ± 0.20), b* (43.24 ± 0.10), chroma (65.62 ± 0.10) and hue angle (36.64 ± 0.18); highest total phenolics (211.57 ± 0.13 mg gallic acid equivalent (GAE)/100 g); and antioxidant properties analysed using DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) (0.59 ± 0.005 μL/mL), FRAP (ferric reducing antioxidant power) (0.63 ± 0.004 μL/mL) and ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid)) (0.58 ± 0.005 μL/mL) assays. The LC‐MS/MS analysis of gac fruit carotenoid pigment concentrate indicated the presence of various health‐beneficial bioactive compounds such as flavonoids, phenolic compounds, terpenoids, diterpenoids, triterpenoids, alkaloids, glycosides and saponins, benzopyrans and phenylpropanoids, macrolides, fatty acid derivatives and glycosylmonoacylglycerols. These results demonstrate the potential of gac fruit as a valuable natural source of red pigment for food applications and show that ethyl lactate is an effective and eco‐friendly solvent for optimising carotenoid recovery.