Natural-Based Antioxidant Extracts as Potential Mitigators of Fruit Browning

Abstract

Fruit enzymatic browning (EB) inhibition continues to be a challenge in the Food Industry. This physiological disorder results mainly from the oxidation of natural phenolic compounds by polyphenoloxidase (PPO) and peroxidase (POX) leading to the formation of brown pigments. EB can be controlled with the application of antioxidants, reducing/inhibiting the activity of these oxidative enzymes. In this study, strawberry tree (leaves and branches) and apple byproduct were the natural-based extracts (NES) selected, as potential tissue browning inhibitors, within a first screening of fifteen natural-based extracts with antioxidant properties. Phenolic profile, total phenolic content and antioxidant activity of the selected extracts were also performed as well as their depletion effect on the oxidative enzyme’s activity and browning inhibiton in fresh-cut pears. Strawberry tree extracts (leaves and branches) revealed higher total phenolic content (207.97 ± 0.01 mg GAE.gNES−1 and 104.07 ± 16.38 mg GAE.gNES−1, respectively), confirmed by the plethora of phenolic compounds identified by LC-ESI-UHR-QqTOF-HRMS and quantified by HPLC. This phytochemical composition was reflected in the low IC50 against PPO and POX obtained. Despite the lower phenolic content (6.76 ± 0.11 mg GAE.gNES−1) and antioxidant activity (IC50 = 45.59 ± 1.34 mg mL−1), apple byproduct extract showed potential in delaying browning. This study highlights the opportunity of byproducts and agricultural wastes extracts as novel anti-browning agents.

Impact of Extraction Process in Non-Compliant ‘Bravo de Esmolfe’ Apples towards the Development of Natural Antioxidant Extracts

“…Likewise, in the ORAC method, CET followed by MAE BE apple extracts showed the highest antioxidant activity in the ABTS method, which is positively correlated (R 2 = 0.9644) with the higher TPC reported above. Furthermore, this behaviour has also been reported by Gómez-García et al [50] and Dias et al [51], who demonstrated a good correlation between total phenolic compounds and the antioxidant activity of melon peels and strawberry tree extracts, respectively, indicating that phenolic compounds are major contributors to antioxidant activity.…”

The Impact of Plant-Based Coatings in “ROCHA” Pear Preservation during Cold Storage: A Metabolomic Approach

“…Sharma and Rao [17] reported that a xanthan gum-based edible coating incorporated with cinnamic acid led to a significant reduction of the oxidative browning process, which ultimately preserved the organoleptic characteristics of fresh-cut pears. Recently, Dias et al [18] selected, amongst fifteen natural-based extracts with antioxidant properties, strawberry tree (leaves and branches), as well as apple pomace methanolic extracts, as the most promising mitigators of fruit browning in fresh-cut pears. Total phenolic content of strawberry tree extracts (leaves and branches) were 207.9 mg and 104.1 mg GAE/g extract, respectively, and 6.8 mg GAE/g extract for apple pomace.…”

Spicy Herb Extracts as a Potential Improver of the Antioxidant Properties and Inhibitor of Enzymatic Browning and Endogenous Microbiota Growth in Stored Mung Bean Sprouts

“…As reported in the literature, the applied solutions are a rich source of phenolic compounds [ 62 ]; thus, it was assumed that they may increase the pro-health properties of stored mung bean sprouts. It has been suggested that functional solutions are responsible for sprout fortification with phenolics; however, they rather act as elicitors, inducing de novo synthesis of phenolics.…”