Using some non-thermal techniques as a new processing to produce safe, high-quality orange juice that is very rich in phytochemicals

Abstract

Objective: the goal of this study was to compare the effects of novel processing techniques thermal processing, pulsed electric field (PEF), orange peel extract (OPE), and ultraviolet (UV) on the physiochemical, microbiological inactivation, and sensory qualities of orange juice that was produced. Methods: using standard procedures, a phytochemical analysis was conducted, both quantitative and qualitative. Orange juice samples were subjected to UV light for 20 minutes using a germicidal fluorescent UV lamp, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method was used to measure the antioxidant activity and agar well diffusion technique was modified to assess antimicrobial activity. Results: The treatments could be applied singly or in combination (TOPE+UV, TOPE+PEF, TPEF+UV, and TOPE+PEF+UV). Orange juice samples underwent the following non-thermal treatments: a pulsed electric field (18.5 kV/cm for 500 µs at 100 Hz) for one-minute, thermal processing (at 90 °C for five minutes), non-thermal processing (UV treated at 25 °C for 20 minutes), and addition of 300 µl phytochemical-rich orange peel extract/100 ml juice. The ascorbic acid degradation for juice that was not thermally processed ranged from 11.11 to 20.5%, but thermal processing produced a higher percentage of degradation (62.8%). Some non-thermally processed juice samples had significantly higher carotenoid extractability (p<0.05) when compared to the control and thermally processed juice samples. Additionally, all non-thermally processed juice samples caused a critical increment (p<0.05) in the all-out phenolic content contrasted with the control and thermally treated juice tests. This resulted in the non-thermally processed juice samples having the highest antioxidant capacity compared to thermally processed juice samples. Compared to the control, thermal and non-thermal processing showed a discernible decrease in the microbial burden. Additionally, the sensory scores of the non-thermally processed samples were greater than those of the thermally processed sample but lower than those of the control sample. Conclusion: the results obtained are consistent with the preservation of orange juice while maintaining its quality attributes through the use of non-thermally processed juice. To produce fruit and vegetable juices with excellent nutritional value and pleasing flavours, heat treatment can be substituted with UV, PEF, and OPE technologies.