Quality evaluation of ozone-processed Kinnow (Citrus reticulata Blanco) juice at ambient temperature

ABSTRACT

Non-thermal processing has been developed to increase the quality and storage life of fruit juices in response to consumer desire. Ozonation is a recently developed method that generates volatile oxygen atoms that can eliminate a broad spectrum of microbes and extend the shelf stability of food products. The present research was intended to investigate the ozone processing on the physicochemical characteristics, microbiological quality, sensory attributes, and antioxidant potential of Kinnow juice. In this study, Kinnow juice was processed to 150 mg/h of ozone gas at a constant concentration for 5, 10, and 15 min. The sample was then taken in a plastic container and stored at 35°C ± 2 for three months. The results revealed that ozone processing had a significant (p˂0.05) effect on the total phenolics (TP) contents, total flavonoids (TF) contents, total soluble solids (TSS), acidity, total antioxidant activity (TAA) and DDPH radical scavenging activity of Kinnow juice. In addition, the ozonation application also significantly (p˂0.05) decreased the population of the microbes when the ozone time was increased from 5–15 min. Among the treatments, it was observed that T₃ had the highest TSS, acidity, TF contents, TAA, and DDPH radical scavenging activity values and the lowest mold and plate counts. Regarding sensory qualities, T₀₊ showed the highest sensory score during storage. Thus, it may be concluded from the findings of our study that ozone application improved the quality of Kinnow juice by increasing TSS, phytochemicals and decreasing the microbial population, thereby prolonging their shelf life.

KEYWORDS:

• Kinnow juice
• Ozone treatment
• Physicochemical characteristics
• Antioxidant potential
• Microbial counts

Author contributions

A.I, M.N and A.A performed the methods and investigation. T.M.Q, W.K and F.M conceptualization, funding acquisition and writing of original draft. S.R, I.A.M.A and M.Z.K helped in writing of this manuscript. While A.R, A.N and M.T.N helped in software, MZK and W.K supported in analysis and supervision of research work, I. A. M. A. validation, visualization, funding acquisition, and writing – review and editing. All authors have read and agreed to the published version of the manuscript.

Acknowledgments

The authors are highly obliged to the University of Sargodha (UOS), and IT Department, Higher Education Commission (HEC, Islamabad) for access to journals, books and valuable database.

Disclosure statement

No potential conflict of interest was reported by the author(s).