Application of D‐optimal design for automatic solvent extraction of carotenoid from orange peel

Abstract

Automatic solvent extraction (ASE) was employed to acquire orange peel extract rich in carotenoid by means of several solvents (hexane, heptane, and chloroform). D-optimal design was used for the design of experiments, modeling the experimental data, and optimization of the extraction process. Selected process parameters (extraction time, particle size of the peel, and solvent type) for the current ASE system were found statistically significant at p < .0001. The highest effect was achieved by particle size, followed by extraction time and solvent. The maximum β-carotene yield (86.85 mg per g fresh peel) was reached by 1.53 mm particle diameter peel material with heptane for ~46 min of ASE time. Then, carotenoid-rich extract was applied as a natural food additive to increase the oxidative stability of the sunflower oil by increasing the induction time more than twice. Practical applications Considering the fact that more than 50% of the orange fruit includes peel with respect to weight, valorization of this waste by-product should be evaluated in terms of “zero waste economy.” Finally, carotene extract produced under optimum conditions has also been studied for a practical food application. Sunflower oil was chosen as the model food product, since the concerned food is the most consumed product, which has a relatively short shelf life for the producers and consumers. The aim of this last step was to evaluate this smart additive in oil. In this way, it will be possible to prevent synthetic applications.