A comparative analysis of the proximate and mineral composition of whole Citrus limon and Citrus clementina as a prospective alternative feed resource for livestock farming in South Africa

Abstract

Citrus is a well-known vital fruit grown in South Africa. The presence of important bio-nutrients and metabolites within the different Citrus fruits indicates their significant nutritional qualities. This study is aimed to evaluate the proximate and mineral components of whole Citrus limon and Citrus clementina while considering them as prospective feed material for livestock farmers in South Africa. The nutritional evaluation was done using standard analytical procedures of the Association of Official Analytical Chemists (AOAC). The mineral constituents of the whole citrus samples were analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES). From the result, the nutritional analysis showed that the whole C. limon contains significantly higher moisture content (14.13 ± 0.57) and fiber content (24.48 ± 0.61) than C. clementina (11.41 ± 1.24 and 20.66 ± 1.07). Meanwhile, C. clementina had a significantly higher protein value (8.65 ± 0.04) compared to C. limon (5.53 ± 0.10). Furthermore, the whole C. clementina had significantly higher K, Na, P, Zn, and Na+/K+ (1513.33 ± 16.99, 53.33 ± 4.71, 160.00 ± 0.00, 4.80 ± 0.00, and 1.09 ± 0.01) than the whole C. limon (1356.67 ± 20.55, 30.00 ± 0.00, 133.33±4.71, 1.67 ± 0.09, and 0.80 ± 0.02), respectively. While C. limon had significantly higher Ca, Mg, Mn, and Fe (593.33 ± 4.71, 160.00 ± 0.00, 1.00 ± 0.00, and 4.53 ± 0.25) compared to C. clementina (483.33 ± 4.71, 136.67 ± 4.71, 0.80 ± 1.11, and 3.43 ± 0.05). The study revealed variations in some nutritional and mineral components of whole C. limon and C. clementina; however, both citrus fruits have the potential to be explored for more significant livestock nutritional use in South Africa.