Abstract:
Moringa (Moringa oleifera) is a multipurpose tree that has amazing nutritional, healing, and preventative potentials. It has been identified as one of the most assuring species in ameliorating/improving micronutrient malnutrition. However, the fresh Moringa leaves tend to lose quality over time due to short shelf-life, approximately 2 to 3 days. Therefore, in this study, different drying methods were investigated to assess the preservation of nutrients. Moringa leaves were harvested during the summer season from December 2022 to March 2023 and taken to the University of Limpopo Plant Production laboratory, where the treatments were laid out in a Complete Randomized Design (CRD). Moringa leaves were subjected to sun drying (1), shade drying (2), oven drying at 30 °C (3), and oven drying at 60 °C (4) to determine the influence of drying methods in terms of maximum preservation of nutrients. Each treatment had 5 replications of trays for precision and validation of the results. The nutrients of the leaves were determined using standard analytical methods. Data were analysed and interpreted using one-way ANOVA using GenStat (2018). The differences between the treatment means were compared for significance at a 5 % probability level using the Least Significant Difference (LSD) test. The findings from this study revealed a significant difference (p<0.05) among the drying methods in moisture, fat, ash, magnesium (Mg), phosphorous (P), potassium (K), and calcium (Ca). Iron (Fe) at 94.5 mg, ash at 12.17 %, potassium (K) at 1.43 %, and phosphorous (P) at 0.32 % were found statistically superior from samples dried in the oven at 30°C. The study revealed the shortest drying period from the leaves dried in the sun and oven at 60 °C drying method, which took 24 hours for the complete moisture loss. There was no significant difference among the drying methods in the Protein, zinc (Zn), and Sodium (Na) content. The study showed a significant influence of drying methods on the composition of chemicals and nutrients in Moringa leaves. Therefore, oven drying method at 30 °C is recommended to enhance the quality of dried Moringa leaves to meet standards of food security in terms of nutrient retention.
