Physicochemical composition of Tamarindus indica L. (Tamarind) in the agro‐ecological zones of Uganda

Abstract

The relationships between the physicochemical composition of Tamarindus indica pulp and seeds, and agro‐ecological zones and land use types were assessed in Uganda. The objective was to determine the relationship between the physicochemical composition, agro‐ecological zones, and land use types. The samples were processed by manually depulping the T. indica pods, sun‐drying the pulp and seeds, and grinding into powder. The powdered samples were analyzed for β‐carotenoids, vitamin C (ascorbic acid), calorific value, crude oil, acid, and peroxide values. Data were analyzed using ANOVA in the general linear model (GLM). Principal component analysis (PCA) was used to relate the physicochemical properties to the agro‐ecological zones and land use types. There were significant differences (p ≤ .05) in the physicochemical composition variables between agro‐ecological zones and land use types. Land use types showed strong correlations with physicochemical properties while agro‐ecological zones did not show correlations. The results show that in terms of general properties, T. indica pods provide a valuable, rich, and exceptional source of vitamin C, compared to many widely consumed indigenous and conventional fruits and vegetables. The pods from land use types characterized by natural habitats had relatively more nutrient levels than the land use types influenced by anthropogenic activities.

Proximate composition of wild and on-farm Tamarindus indica linn fruits in the agro-ecological zones of Uganda

“…Most fruits have very high water content (80-95%) at harvest and the rate of water loss from fruits is affected by the shape and structure of the produce, the plant factors as well as the environmental conditions such as temperature and relative humidity. 29 The observed moisture contents variations are probably due to the differences in eco-factors and climatic factors that differ with AEZs which agrees with Okello et al 14,15 However, the low moisture content in the study's T. indica seeds are probably due to the nature of sample (dry), double protective nature of both the pod and seed coat (testa) to prevent excessive moisture loss, which corroborates with. 30 While the differences in the shape and structure of T. indica fruits and seeds could have also greatly contributed to the observed differences.…”

“…In each sampling site, a total of five T. indica trees were selected per land use type based on ease of access, good health indicated by absence of obvious signs of pests, diseases and fire, and presence of visibly good mature pods. The sample trees were located at least 200 meters apart, since trees close to each other may have the same defects such as pests and diseases, fire and hailstorm effects as described by Okello et al 14,15…”

“…Storage conditions, duration before analysis, variation in processing methods, harvest and post-harvest handlings, probably contributed to the observed differences and agrees with other studies. 14,15 The fruit species show different behaviour depending on moisture and dry matter. 32 Water-rich fruits and vegetables provide human natural sugars, amino acids, mineral calories and vitamin requirements.…”

“…13 The species is a native of Uganda and Africa, and has multipurpose uses that is domesticated and widely distributed as wild plant. 14 It is commonly found near homesteads, on-farms, along roadsides, market places, in many public places and also grows in neglected places (such as swamps and invaded by anthills) where they are extensively used by smallholder farmers. 14,15 The T. indica fruit is economically important to the population due to its ability to provide the household with incomes when sold in the local markets, local juice (sweet and sour taste), timber and fodder.…”

“…14 It is commonly found near homesteads, on-farms, along roadsides, market places, in many public places and also grows in neglected places (such as swamps and invaded by anthills) where they are extensively used by smallholder farmers. 14,15 The T. indica fruit is economically important to the population due to its ability to provide the household with incomes when sold in the local markets, local juice (sweet and sour taste), timber and fodder. According to Okello et al 15 the species is used as an agroforestry and shade tree, cures many ailments (example, meningitis) and flowers are good for bee forage.…”