COMPARATIVE STUDIES OF THE SUGAR AND MINERAL CONTENTS OF INDUSTRIALLY PROCESSED FRUIT JUICES SOLD WITH FRESHLY PREPARED FRUIT JUICES
The sugar and mineral levels of industrially processed fruit juices (mainly 100% and 50% fruit juices) sold to consumers in Enugu state, Nigeria were determined and compared with that of freshly prepared fruit juices. The liquid nature as well as the versatility of juice has increased the ease with which fruit juices can be altered with sugar, contaminants, water or inferior juices by unethical suppliers. This research was performed to address the potential concern that industrially processed fruit juices (especially those with ‘100% natural’ and ‘no sugar added’ label) may differ in quality with respect to sugar and mineral contents (including heavy metal contents which is deleterious to quality) from extracted juice of fresh fruit, as well as to address in part the ongoing public health concerns of excessive sugar consumption, micronutrient malnutrition and heavy metal contamination. The fruit juices tested included apple, orange, pineapple and red grape juices. All industrially processed fruit juices and fresh fruits used were purchased in Enugu state, Nigeria. The fresh fruits were juiced and all samples including industrially processed and the freshly prepared fruit juices were tested for total soluble solid (TSS) content, fructose, glucose, sucrose, Na, K, Mg, Ca, P, Fe and heavy metals contents such as Cu, Zn, As and Pb. Findings from the analysis of the TSS content of fruit juice samples demonstrated no significant (p > 0.05) difference between the industrially processed and freshly prepared fruit juices; however, difference in sugar and mineral levels between industrially processed and freshly extracted fruit juices was significant (p < 0.05). Industrially processed fruit juices contained higher glucose, sucrose, Na, Ca, P, Cu and Zn contents, and lower fructose, K and Mg contents when compared to freshly prepared fruit juices. There was no significant (p > 0.05) difference in iron (Fe) and arsenic (As) contents of industrially processed fruit juices when compared with the freshly extracted juices. Lead (Pb) was not detected in any of the samples. This study demonstrated no quality issues of concern in relation to the products because all the parameters considered in the study were within the standard acceptable range for fruit juices and nectar.