Influence of Processing and Packaging on the Nutrients of Fresh Fruits from Local Markets of Ogun State, Nigeria

A study of the effect of processing on the nutritional values of fresh fruit juices of orange, mango and pineapple was conducted and the results show that apart from the carbohydrate content in orange juice, other values were lowered to different extents as a result of processing. The processed orange juice showed a carbohydrate value of 2.960mg/ml as against the fresh orange juice showing 2.030mg/ml amounting to over 30% increase possibly from fortification using supplements. All other values dropped to varying amounts like total protein 28%, titrable acidity 27% and pH 13%. There was no significant difference in the carbohydrate content of the fresh and processed mango juice about 1.0% whereas the total protein lowered from 12.41mg/cm³ to 6.041mg/cm³ equal to 51%. The titrable acidity also showed a fall from 1.05g/1000ml to 0.66g/1000ml equal to 37% while the pH dropped from 4.92 to 3.44 equal to 30%. Also there was no significant change in the carbohydrate content of fresh and processed pineapple juice. The slight drop from 2.100mg/ml to 2.030mg/ml amounted to 3.3%. However, the total protein dropped from 10.48mg/cm³ to 5.161mg/cm³ equal to 41.2% while the titrable acidity dropped from 2.22g/1000ml to 2.01g/1000ml equivalent to over 9.45%.  The pH only dropped from 3.85 to 3.07 equal to 2.0%