Product Development: Nutritional Value, Processing and Utilization of Indigenous Fruits from the Miombo Ecosystem - Indigenous Fruit Trees in the Tropics: Domestication, Utilization and Commercialization - page 299

16.4.2 Nutritive value of indigenous fruit products

Processing affects the composition of finished fruit products. The physicochemical
characteristics of fruit products (juices and jams) for indigenous fruits and non-
indigenous fruits are shown in Table 16.6 (Saka et al ., 2007). These data indicate
that mango and Uapaca juices have higher pH values (i.e. they are less acidic)
than Strychnos cocculoides (kabeza) and Adansonia digitata (baobab) juices. The
low pH values of S. cocculoides and A. digitata fruits are due to their high acid
level (Saka, 1994). The baobab and kabeza juices are rich in zinc; the former has
a similar copper level to mango juice. All juices exhibit high phosphorus levels
(>200 g/ml). While kabeza has the highest potassium level, baobab juice has

calcium and magnesium levels consistent with higher contents of these elements
in the pulp (Saka, 1994). Laboratory-made baobab and commercially available
juices contain no measurable iron or vitamin C.
The jams, not unexpectedly, contained much higher nutrient levels than the
juices. Processing to make jams results in water removal and thus concentration
of food nutrients (Dietz, 1999; Krige et al ., 2006). These juices and jams would
make a considerable contribution to the daily dietary requirements of children.
For example, an adult consuming 200 ml of V. mombassae juice would take in
the recommended daily amount of 60 mg.

16.4.3 Effect of provenance on chemical composition of Adansonia digitata
fruits

The compositions of five provenances of Adansonia digitata from Malawi are
presented in Table 16.7 (Tembo, 2006). The data show that provenance
significantly affected the physicochemical properties of A. digitata fruits
( P < 0.001). For example, the Chikwawa provenance had significantly higher
contents of vitamin C (ascorbic acid; 347.7 mg/100 g) and reducing sugars
(11.26%) than the other four provenances ( P < 0.001). Fruits from Salima had
the least ( P < 0.001) vitamin C while Mangochi fruits had significantly
( P < 0.05) higher iron contents than other provenances.
Generally, fruits from all locations were acidic and showed significant
differences within provenances. Mangochi fruits were significantly more acidic
( P < 0.05; 2.86%) than the others. The high values are probably due to a high
ascorbic acid content (Saka, 1994). Total soluble solids ranged from 21.8% for
Chikwawa to 32.5% for Dedza ( P < 0.001). The low total soluble solids (%)
contents for Chikwawa provenance is probably due to differences in the
environment. Results of vitamin A analysis revealed that the Mangochi
(60.9 mg/kg) and Mwanza (54.7 mg/kg) provenances had the highest vitamin A
levels ( P < 0.001). Fruits from Chikwawa had significantly lower ( P < 0.001)
levels of vitamin A. This is consistent with the results of Gross (1991), who
observed that areas of high light intensity were associated with higher vitamin
C but lower vitamin A levels.
The mineral content of A. digitata fruits varied significantly among the
provenances. Mwanza and Dedza provenances had significantly higher calcium