Abstract:
Proximate composition (crude protein, moisture, crude fat and ash) and calcium of
Barbus paludinosus locally known as matemba, smoked in traditional and improved
smoking kilns was compared. This species makes the most important fishery in Lake
Chilwa, Malawi. Matemba is also highly nutritious because it is consumed whole due
to its small size. Most of the catch is either sun dried or smoked. However, knowledge
that heat processing compromises nutrient content in food products, underpins the need
for assessing the magnitude of nutrient changes or losses in the respective processed
products. In this study, freshly caught fish samples were obtained from Lake Chilwa
(Southern Malawi), smoked and analysed for proximate composition. Crude protein
significantly increased (61.00 ± 0.02) (P<0.05) and decreased (59.50±0.03) (P<0.05)
from the normal (fresh samples – 60.50 ± 0.01) in fish processed using the improved
and traditional smoking kiln respectively. Fish smoked in the traditional kiln showed
higher amount of moisture (19.00 ± 0.02) than the improved kiln (18.00 ± 0.03)
(P<0.05). Higher amount of crude fat, ash and calcium were retained in fish smoked
in the traditional smoking kiln compared to the improved smoking kiln (P<0.05).
Summary results suggest that the improved smoking kiln is better in preserving
nutrients in fish over the traditional smoking kiln. Of much interest in the improved
smoking kiln, is the higher protein and lower moisture retention. This suggests that
fresh fish smoked in the improved kiln is more nutritious but also may have a longer
shelf life due to lower moisture which is a medium for microbial growth responsible
for fresh food spoilage. The improved smoking kiln should therefore be recommended
also because it uses less firewood than the traditional smoking kiln. However, the
traditional smoking kiln may not be eliminated completely owing to products with
higher fat content which is also required by the human body