Determination of Vitamin C Concentration in Various Fresh Orange and Lemon Samples from Janzour Region Using Volumetric Titration

Abstract

Vitamin C is an essential nutrient crucial for human health, playing a vital role in numerous physiological processes, including immune system support and collagen synthesis. Citrus fruits, such as oranges and lemons, are recognized as rich sources of this vitamin. The primary purpose of this study is to determine the vitamin C concentration in various fresh orange and lemon juices. The samples were randomly collected from the local market in Janzour. The study included 18 samples representing 6 different citrus varieties (3 samples per variety). Vitamin C concentration was statistically estimated using a titrimetric method with a standardized solution of 2,6-dichlorophenolindophenol (DCPIP) as the titrant. The obtained results revealed some kind of variations in vitamin C content among different citrus varieties and even within samples of the same variety. Abu Surah orange samples exhibited the highest vitamin C concentration (mean range: 38.9-41.6 mg/dl), while sweet orange samples had the lowest (mean range: 5.1- 8.5 mg/dl). Vitamin C concentrations in other varieties ranged as follows: Sour orange: 9.22-24.9 mg/dl, Mandarin: 9.0 -16.2 mg/dl, Tarocco: 28.2-33.3 mg/dl, and Lemon: 14.5-15.8 mg/dl. These results showed evidently that vitamin C levels were varied even within the same sample type. Such variations would draw attention to the importance of choosing varieties when searching for food sources of this vital nutrient.