Residues from orange processing are being continuously generated in vast amounts due to the increasing demand for this fruit and its byproducts worldwide. The valorization of Orange Residues is challenging in contrast to conventional “lignocellulosic residues” since this fruit-derived biomass contains high amounts of pectin and an extractive fraction rich in sugars, essential oils, and polyphenols. The relative amounts of these fractions are highly influenced by the juice/pulp extraction process. Even though several studies have explored how to produce added value from this biomass, it is necessary to compare how different techniques and operating conditions influence the bioactive compounds that can be recovered and the remnant biomass after processing. This study compares essential oil extraction, solvent extraction, and acid hydrolysis for fermentable sugar and pectin production to elucidate a feasible sequence for a biorefinery from Orange Residues. From our results, it was proposed a technically feasible sequence that maximizes the yields of i) essential oils (0.70 ± 0.05 g/ 100 g DM) from steam distillation (4 h, 1500 W), ii) naringin (0.19 g/100 g DM), hesperidin (1.27 g/100 g DM), and glucose (3.9 g/100 g DM) from solid-liquid extraction (Ethanol 61.6 % (w/v), 45.8 °C, 155.5 min, and 5 % (w/v) biomass load), iii) pectin (25.24 g/100 g DM) from citric acid hydrolysis (pH 1.5, 90 °C, 82.1 min, and 5 % (w/v) biomass load), and iv) glucose (12.41 g/100 g DM) and xylose (10.13 g/100 g DM) from sulfuric acid hydrolysis (Sulfuric acid 0.68 % (w/v), 121 °C, 24.1 min, and 7.32 % (w/v) biomass load), in a biorefinery scheme.

In the last few years, healthy foods have increasingly attracted consumers' interest, leading to an increase in sales worldwide. Using by-products from the agroindustry to produce healthy/fortified foods is a promising approach since peels and seeds of fruits have significant amounts of bioactive compounds. In this sense, this work evaluated the possibility to add fractions recovered from residues of orange, lime, and peach palm in a food product. First, the proximate, ultimate, and chemical composition of the residues was determined to identify the main substances that could be valorized. Then, the selected high-value-added molecules extracted from fruit residues were used to formulate a high-fiber brownie. A Box-Behnken experimental design was used to determine if fat replacement, flour replacement, and the addition of encapsulated extracts influenced the food product's color, texture, and humidity which were determined from the analysis of the texture profile of the samples. It was possible to identify with the help of an electronic tongue a formulation with similar properties to a commercial brownie but with enhanced functional properties due to the novel ingredients added, which could potentially improve consumers' health.