Effect Of Ozone and Combined Ozone -Freezing Treatments on The Physico-Chemical Properties and Enzymatic Activity of Sugarcane Juice

Sugarcane juice is a primary raw material for the sugar industry in Egypt and many other countries. It is also consumed fresh as a refreshing beverage rich in nutrients. This study, conducted at the Central Laboratory of Agriculture Climate (CLAC), Dokki, Egypt, during December/January 2023/2024, investigated the impact of ozonation on the biochemical and physiochemical properties of sugarcane raw juice. Sugarcane stalks were crushed to extract the juice, and three volumes (250, 500, and 1000 ml) were subjected to ozone (O3) treatment for three durations (5, 10, and 15 minutes). Results revealed that exposure time, volume, and their interaction significantly influenced various characteristics, including °Brix, total soluble sugars (TSS), reducing sugars, invertase activity, total phenols (TP), total flavonoids (TF), polyphenol oxidase (PPO), and color coordinates. Fresh ozonized juice (250 ml/5 min) exhibited favorable industrial properties compared to 1000 ml. TP content was significantly affected by exposure time and the combination of ozonation with freezing. Correlation analysis highlighted strong, significant negative correlations between reducing sugars and sucrose, reducing sugars and pH, sucrose and TPC, and pH and TPC.