Enzymatic, Phyto-, and Physicochemical Evaluation of Apple Juice under High-Pressure Carbon Dioxide and Thermal Processing

Abstract

In this study, the changes in enzyme activities, total polyphenols, phenolic profile, and physicochemical properties from thermally (25–75 °C) and high-pressure carbon dioxide (HP-CO2) (25–65 °C/20 MPa)-treated apple juice were investigated. The HP-CO2 exhibited complete inactivation of polyphenol oxidase (PPO) at 65 °C, whereas PPO was still active at 75 °C under thermal processing (TP). Similarly, the relative activity of peroxidase (POD) significantly decreased by 71% at 65 °C under HP-CO2 processing, whereas TP was less effective. HP-CO2 and TP treatments at 65 °C reduced the browning degree (BD) value to 0.47 and 0.89, respectively. Thus, HP-CO2 inhibits the browning reactions caused by PPO and POD enzymes at each operating temperature. The concentration of epicatechin and catechin increased significantly with increasing temperature above 45 °C in TP-treated juices. HP-CO2 treatment increased the same phenolic compounds at 35 °C and 9 MPa, whereas high-temperature and -pressure conditions caused insignificant changes in concentration of epicatechin and catechin. Changes in others phenolic compounds were insignificant under TP and HP-CO2 treatment. Overall, HP-CO2 is a promising technology to get high-quality juices with lower enzyme activity.

Health Benefits of Plant-Derived Sulfur Compounds, Glucosinolates, and Organosulfur Compounds

“…The OSCs in Allium plants are thermally unstable and tend to be lost during pasteurization, sterilization, cooking, and drying [ 82 ]. High-temperature processing, such as boiling and autoclaving, exerts negative effects on the bioavailability of organosulfur compounds [ 95 , 96 ]. High-pressure processing (HPP) can also decrease the allinase activity, thereby reducing the antimicrobial, anticancer, and antioxidative properties of Allium plants [ 97 ].…”

Phenolic Compounds from Apples: Reviewing their Occurrence, Absorption, Bioavailability, Processing, and Antioxidant Activity – a Review

“…1.2-fold higher) and have higher antioxidant activity (3.5-fold higher) compared to juices without its addition [Kolniak-Ostek et al, 2013]. Promising results in terms of decreasing the browning of juices were achieved by using high-pressure carbon dioxide treatment [Murtaza et al, 2020]. This processing of juices also increased (-)-epicatechin and (+)-catechin concentrations; however, more studies need to be done to establish the appropriate temperature and pressure conditions to achieve the highest content of phenolics.…”

High-Pressure Carbon Dioxide Used for Pasteurization in Food Industry

“…The remaining peroxidase activity was 61.39% after treatment with CO 2 at 20 MPa and 45 °C for 20 min, whereas, only 29.32% peroxidase activity was preserved when the temperature increased to 65 °C. Without HPCD, peroxidase activity remained at 94.56%, even when the temperature was increased to 65 °C [ 79 ]. When the CO 2 pressure increased to 30 MPa for 30 min, 83% of the peroxidase was effectively inactivated [ 47 ].…”

“…HPCD treatment of below 20 MPa made no big effects on organic acids, a kind of very important nutritional compounds with antioxidant activity in many fruits [ 90 ]. The phenolic compounds, which also possess antioxidant activity, are also not influenced greatly by HPCD treatment [ 79 , 90 ]. However, Murtaza et al [ 79 ] presented that higher temperatures can induce an even greater loss of phenolic content.…”

“…The phenolic compounds, which also possess antioxidant activity, are also not influenced greatly by HPCD treatment [ 79 , 90 ]. However, Murtaza et al [ 79 ] presented that higher temperatures can induce an even greater loss of phenolic content. Furthermore, when higher pressure and higher temperature (60 MPa, 55 °C) were applied, about 30% polyphenols were degraded [ 91 ].…”