Enhancing the functionality of corn starch-based edible films through carotenoid emulsions prepared from yellow carrot pomace: implications on structural, morphological and thermal properties
摘要
Yellow carrot pomace (YCP), a byproduct of juice processing, emerges as a promising and cost- effective source of carotenoids was explored as functional ingredient in edible packaging. In the present study, lyophilized YCP was subjected to carotenoid extraction at different concentrations (15, 25, 35, and 45% (w/v) in 100 mL ethyl acetate followed by delivering the YCP carotenoids in Lemongrass oil emulsions. The YCP carotenoid emulsion was further used in the development of a ternary blended edible film. Our results demonstrated that film’s thickness and water barrier properties were significantly improved by the inclusion of carotenoid emulsion. Additionally, the inclusion provided the benefit of reduced moisture, water solubility and water vapor permeability rates in the film. The addition of carotenoid emulsion increased carotenoids (14.22–32.46 mg mg−1), lutein (8.13–18.71 mg mg−1), zeaxanthin (3.54–9.43 mg mg−1) and phenolic content (3.44–7.48 10−3 mg GAE mg−1), as well as antioxidant properties, with an increase in yellowness value (b*) and opacity while lowering the values for lightness and thermal stability. Further, the Fourier Transform Infrared Analysis confirms the crosslinking of carotenoid functional groups with film-forming hydrocolloids. Carotenoid emulsion films caused agglomerations on the film surface, which reduced the tensile strength and elongation at break, while control films showed a smoother, more compact surface free of fractures as shown by Fourier emission scanning electron microscopy images. Based on these findings, YCP carotenoid films might enhance the nutritional content of packed food products while extending the potential for preservation of food.