Nutritional diversity and economic value of baobab (Adansonia digitata L) root tubers and leaf production

Abstract

Aim of study: Baobab (Adansonia digitata L) is a deciduous indigenous fruit tree that belongs to the family of Malvaceae. A study was conducted to investigate the nutritional value diversity and economic value for baobab root tubers and leaf production. Area of study: The study was conducted in Mangochi district, located in the Southern Region of Malawi. Material and methods: Seeds of baobab were pre-treated and planted in trial plots. The planting was subjected to three treatment factors (season, site, and type of soil). After harvesting, both fresh and dried baobab root tubers and leaves were subjected to nutritional analysis at the Malawi Bureau of Standards (MBS) laboratory in Blantyre, Malawi. Gross profit analysis (GPA) was performed to calculate the following profitability indicators: profit, return on investment (ROI), and net profit margin (NPM). Main results: The results indicate that there were significant (p < 0.001) differences in nutritional values (energy, carbohydrates, protein, magnesium, and potassium) between fresh root tubers and fresh leaves. Fresh root tubers had higher nutritional content in energy and carbohydrates than fresh leaves, while fresh leaves had higher nutritional content in proteins, magnesium, and potassium. On the other hand, there were no significant (p > 0.05) differences in iron, lead, and cadmium between fresh root tubers and fresh leaves. The same trend was observed in dried root tubers and dried leaves. However, dried root tubers and dried leaves had higher nutritional values compared to their corresponding fresh nutrients. Furthermore, baobab root tubers and leaf production were viable with an estimated annual profit of about MK1 million (US$1.2 thousand), a positive rate of return on investment (38.5%), and a positive net profit margin (27.8%) per hectare. Research highlights: The study recommends that baobab root tubers and leaves whether dried or fresh are safe to eat and they are nutritious. Additionally, baobab tubers and leaf vegetables have great potential to be introduced as cash crops among communities in Malawi and the surrounding region.