Lake Malawi Tilapia (
chambo) fish species is widely consumed and forms the most
important commercial fishery in Lake Malawi. However, as a highly perishable
commodity, knowledge regarding how long fresh fish would remain in acceptable and
safe condition in storage is indispensable for consumers and processors. Presently, no
such information exists for the Lake Malawi Tilapia in Malawi. A study was therefore
conducted to estimate shelflife of whole fresh Lake Malawi Tilapia stored in ice (0
°C) for 21 days. Sensory, microbiological and pH analyses were conducted to describe
changes in quality and freshness of the fish with storage time in ice. Shelflife of the
fish was estimated between 16 and 18 days. A strong linear correlation (R
2=0.95) was
observed between sensory demerit scores and storage time in ice. Total bacteria viable
counts and pH at the time of sensory rejection of the fish were 1.6×10
7 cfu/g/cm
2 and
5.84 respectively.
Pseudomonas
and
Micrococcus
bacteria were found in relatively
high numbers throughout the storage period. The study demonstrated that like other
tropical fish, Lake Malawi Tilapia has a relatively longer shelflife. The long storage
life in ice of Lake Malawi Tilapia is advantageous to most small scale fresh fish
sellers and processors especially from rural areas in Malawi who solely depend on ice
as a sole and affordable way of preserving fresh fish.
