Industrial Fruits By-Products and Their Antioxidant Profile: Can They Be Exploited for Industrial Food Applications?

Abstract

Fruit by-products have a low economic value and have proven biological activities, such as antioxidant capacity due to the presence of active compounds. The main objective of this study was to obtain and determine the antioxidant capacity, through DPPH radical assay and β-carotene bleaching assay, of three food grade extracts from apple, lemon, and orange industrial by-products. Furthermore, the extracts were characterized by ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS/MS). LC with diode array detector (LC-DAD) was used for the quantification of the main polyphenols. Lemon extract presented the highest inhibition percentage of DPPH radical (51.7%) and the highest total phenolics content (43.4 mg GAE/g) from the by-products studied. Orange by-product was that with the higher number of polyphenols while lemon extract was that with the highest content of individual phenolics. The by-product obtained from the lemon was that with higher amounts of hydroxycinnamic acids (407 µg/g of by-product), mainly chlorogenic acid (386.7 µg/g), followed by the apple by-product (128.0 µg/g of by-product), which showed higher amounts of rosmarinic and chlorogenic acids. These industrial by-products have great potential as a source of natural antioxidants to be used directly as food additives or to be incorporated in packaging to produce active food packaging.

Chemical Composition, Antioxidant Activity and Cytocompatibility of Polyphenolic Compounds Extracted from Food Industry Apple Waste: Potential in Biomedical Application

“…Fraction C containing seed and core contained the highest concentration of phloridzin compared to peel, a mixture of peel and pulp, and whole parts of AP. Consistent with the results presented in this study, several other studies reported phloridzin as the most abundant polyphenol in AP from different varieties including Idared and Šampion [ 37 , 52 , 53 ].…”

Ultrasound-Assisted Extraction of High-Value Fractions from Fruit Industrial Processing Waste

“…Indeed, the antioxidant capacity values (mg Trolox/g) achieved for both FE and FL samples were higher than those previously reported for mango skin (23.27 ± 62 0.23) and grape seeds (23.15 ± 0.09) using conventional extraction with organic solvents [ 7 ]. The freeze-dried by-products of lemon (33.17 ± 2.94 mg TEAC/g), orange (20.13 ± 0.43 mg TEAC/g), and apple (25.69 ± 0.56 mg TEAC/g) treated using ethanol as the extractive agent also provided lower values [ 13 ]. These results emphasize the relevance of studying the extraction conditions and reinforce the suitability of ultrasonic-probe-assisted extraction.…”

“…Due to their high moisture content (80–90%) and acidic pH, fruit by-products are perishable and difficult to store, and so it is necessary to apply a pretreatment prior to the bioactive compound extraction [ 12 ]. The selection of an adequate dehydration treatment method under the most favorable conditions is very important to extend the useful life of the waste without jeopardizing its bioactive features, since the drying of fruit by-products can reduce their antioxidant properties [ 13 ]. The subsequent selection of the extraction method is another key factor for achieving high yields, preventing the degradation of compounds, reducing the use of organic solvents, and saving time and energy [ 14 ].…”

Antioxidant Capacity and Phenolics Profile of Portuguese Traditional Cultivars of Apples and Pears and Their By-Products: On the Way to Newer Applications

“…The total flavonoid content method was performed according to Barbosa et al [ 32 ]. In this assay, 1 mL of sample was mixed with 4 mL of ultrapure water and 0.3 mL of sodium nitrite (50 mg/mL).…”