International Journal of Aquaculture, 2018, Vol.8, No.15, 112-120
112
Research Article Open Access
Processing and Storage Effects on the Proximate Composition, Changes in
Heavy Metal Contents and Total Volatile Base Nitrogen (TVB-N) of Selected
Fish Species in Osun State, Nigeria
Faith E. Bala, Abiodun V. Ikujenlola , Taiwo O. Omobuwajo
Department of Food Science and Technology, Obafemi Awolowo University, Ile-Ife, Nigeria
Corresponding author Email
International Journal of Aquaculture, 2018, Vol.8, No.15 doi
Received: 28 Apr., 2018
Accepted: 17 May, 2018
Published: 08 Jun., 2018
Copyright © 2018
Bala et al., This is an open access article published under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Bala F.E., Ikujenlola A.V., and Omobuwajo T.O., 2018, Processing and storage effects on the proximate composition, changes in heavy metal contents and total
volatile base nitrogen (TVB-N) of selected fish species in osun state, Nigeria, International Journal of Aquaculture, 8(15): 112-120 (doi
Abstract
This study assessed the effect of location, processing methods and storage on the proximate composition, heavy metal
contents and total volatile base nitrogen (TVB-N) of some selected fish species from Asejire and Opa reservoirs, Osun state. The fish
species were processed by salting, drying, smoking, storing (25 ± 2°C) and analyzed for proximate composition, heavy metal
contents and TVB-N. Protein, fat, ash and carbohydrate increased after processing but moisture content reduced. During storage the
heavy metal concentrations reduced but moisture content and TVB-N increased; indicators of deterioration. The study concluded that
processes such as smoking, drying and salting contributed to the keeping quality of the fishes and reduced the bio-accumulated heavy
metal concentrations of the fish species.
Keywords
Arsenic; Drying; Salting; Smoking; Total volatile base nitrogen
Background
In human nutrition, fish and fish products play important role as good source of biologically valuable proteins,
fats and fat-soluble vitamins (Belitz et al., 2009; Thaker et al., 2017). There has been dramatic increase in the
fishing industry catch in tonnage during this century. In 1900, the catch was approximately 4 million tonnes,
meanwhile it had risen to 129 million by 2001 (IOM, 2007). Fish consumption is recommended as an important part
of the human diet, due to the high nutritional value of ω-polyunsaturated fatty acids present in fish (IOM, 2007).
In Nigeria, water bodies contain different types of fish species that serve as food and an economic resource for the
country (Osibona et al., 2006). Some of the common species include croakers, catfishes, tilapias, threadfins, soles,
and the clupeids accounting for about 90% of Nigeria’s fishery (FDF, 2004). About 69.6% of the total fish supply
available to Nigeria is from fresh water fish (FOS, 1990).
In Africa, the fisheries sector provides means of livelihood to about 5 percent of the population, about 35 million
people, mostly artisanal fisheries (FAO, 2001). In Nigeria fishing is done on a continuous basis in Nigeria, but a
remarkable and significant harvest occurs around the seasonal catch from July to September each year. Hence, in
order to ensure that fish is available throughout the year, especially during the lean season, it is imperative to
process the fish in large quantities and preserve in good condition until its use is required (FAO, 2001).
One of the constraints to such an attainment aside seasonality of fish food of fish that makes it extremely
perishable is the very high moisture content. Deterioration set in shortly after fish dies if no preservative or
processing measures is applied to the fish, a number of microbial and physiological deterioration set in and
thereby degrade the fish (Davies and Davies, 2009). According to the report of FAO (2001) in the tropics where the
ambient temperature is high, fish spoils within 12-20 hours of being caught, depending on species and size
therefore, a reasonable percentage of the landed catch is processed to extend the shelf life of most of their catch by
artisanal methods (FAO, 2001).
Traditional methods of fish preservation such as drying, salting and smoking have been practiced perhaps longer
than any other food preservation technique. Modern developments have centered on understanding and controlling
