Effects of phenolic enrichment on vitamin C and antioxidant activity of commercial orange juice

Abstract

The autoxidation process of vitamin C in orange juice is the most important cause of quality loss during its storage. We evaluated the enrichment with different concentrations of a phenolic extract in a commercial orange juice for some qualitative parameters such as the content of vitamin C, phenolic compounds, and antioxidant activity. The lowest concentration of phenols produced the most stable enriched juice. In particular, we observed an inverse correlation between phenolic concentration and vitamin C retention in enriched juices. DPPH assay results confirmed this trend, correlated more to the vitamin antioxidant effect. TEAC results instead, were similar for the different juice samples, probably influenced by the phenolic content. The application of this study is the production for the industry of new functional drinks such as juices enriched with phenolic ingredients that show increased stability concerning those without addiction.

Changes in Physicochemical, Free Radical Activity, Total Phenolic and Sensory Properties of Orange (Citrus sinensis L.) Juice Fortified with Different Oleaster (Elaeagnus angustifolia L.) Extracts

“…Moreover, the DPPH free radical activity and total phenolic compounds of control significantly decreased (p < 0.05) from ~88.72 to 77.77%, and from 200.75 to 168.32 mg GAE/g, respectively. The results were in agreement with data reported by Romeo et al [33], where the antioxidant activity in orange juice decreased during storage time. Between the aqueous oleaster extract 25% and alcoholic extract 5%, together with the control, more resemblances (p > 0.05) in DPPH free radical activity and total phenolic compounds were found.…”

“…Additionally, the increase in pH values may be due to the citric acid (acidity) decrease, which has been reported elsewhere [33,34]. In the current work, both total acidity (~0.63 mg/100 g) and total sugar content (~6.15 mg/g), respectively, peaked at the control and hydro-alcoholic oleaster extract 25% (refer to Figure 2a,c).…”

“…Notably, the critical factor affecting the juice spoilage, among others, includes the pH. Additionally, the microbial spoilage in fruit juices has been represented by cloud loss, CO 2 production, off-flavor development, as well as sensorial changes, which would bring about a loss in the product value [ 32 , 33 ]. The changes in total acidity, pH, total sugar content, and sucrose values of orange juice subject to different oleaster extracts are shown in Figure 2 .…”

“…Different authors have recommended the DPPH assay as an accurate/easy method to measure the antioxidant activity of orange juice, as well as those made from other fruit products [ 33 , 37 , 38 ]. For emphasis, the oleaster extracts have been added in this study given our aim to produce a beneficial orange juice that would become enriched with both phenolic compounds and antioxidant properties.…”

Functionalization of a Vegan Mayonnaise with High Value Ingredient Derived from the Agro-Industrial Sector

“…Mayonnaise represents one of the most widely consumed sauces in the world [6]: it is a semisolid oil-in-water emulsion, prepared traditionally with egg yolk and 60-80% of oil. The presence of egg in mayonnaise formulation is important both for emulsion and for the taste and color but it is a critical point for the health aspect due to the cholesterol amount [7].…”