Production of clear and naturally cloudy lemon juice concentrate and determination of quality parameters

In this study, lemon juice obtained from Interdonato variety was treated with different enzymes and enzyme concentrations as depectinization processes to produce clear lemon juice and also naturally cloudy lemon juice and their concentrates. Effects of the processing steps on the quality were investigated during the lemon juice production and the obtained concentrates were stored at -25oC for 180 days. Some quality and components analysis during storage were evaluated in lemon juice and their concentrates.The results showed that Novozym 33095 had the best depectinization effectiveness. Total pectin content of lemon juices decreased rapidly following the enzymation stage and couldn?t be detected following the filtration. Viscosity values decreased after pulp separation and the largest reduction was observed with the filtration. After clarification and filtration, NTU values decreased significantly. While L value increased with the processing steps following the pasteurization a and b values decreased. Browning index values increased following the thermal processing steps including pasteurization, enzymation and clarification. Hydroxymethylfurfural(HMF) values started to rise with pasteurization and continued to rise with enzymation and clarification during the clear lemon juice production. Antioxidant activity values decreased for all three concentrations following the enzymation. Ascorbic acid values of the clear and naturally cloudy lemon juices and their concentrates decreased during the processing steps and the storage. Fifteen phenolic and five carotenoid compounds were determined in the lemon juice and the most abundant ones were hesperidine and ß-cryptoxantin. Mineral matter content of lemon juices increased with the clarification. According to sensory analysis, naturally cloudy and clear lemon juices obtained from Novozym 33095 application were the most preferred ones.