International Journal of Aquaculture, 2018, Vol.8, No.7, 43-52
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Electric oven drying is one of the several drying methods which is conventional supplied by electric power. It is
the most convenient method to dry a fish as it operates and sets depending the desire and condition of the final
product requirement of consumers. Oven drying method is the fastest and safer than the open sun drying method.
Fish dried in an oven dryer showed an increase in nutritional value than a fish dried in open sun dryer (Ali and
Karimi reza abad, 2015). Hubackova et al. (2014) was compared the drying performance of solar and electric
dryers and found that electric oven dryer can reduce the moisture content of a fish to 2.22% and 3.12% after 24
hours respectively. It has been also reported the drying was better in electric oven, due to the uniform drying
conditions compared to solar drying (Hubackova et al., 2014). Ali and Karimi reza abad (2015) indicated in their
results of research work the oven drying method is a good effective method to decrease moisture level where
activities of microorganisms can be inhibited and to achieve high protein content (85.66%). It was also suggested
that drying fish with electric oven method is more suitable for feeding health nutrition and good shelf life which
can store for long time (Ali and Karimi reza abad, 2015). Drying fish using oven drying, low cost drying
technology, for developing dried fish protein has been reported (Chavan, 2008). Huda et al. (2000) recommended
that drying fish at 60°C for 12 h is important to reach less than 10% moisture content of fish protein powder.
3.3 Preparation, composition and characteristics of fish powder
Shaviklo (2015) commence the idea of processing fish powder via solvent extraction method; however it retains a
solvent taint even after prolonged steam stripping under vacuum. Numerous researchers have been worked on
production of edible fish powder by solvent extraction method to remove fat thereby making the process costly
(Solanki, 1977). In findings of nutritional content and quality attributes, fish with low fat content has been chosen
to produce edible fish powder and concluded that, fish with low fat content are recommended for preparation of
edible fish powder.
Venugopal et al. (1994) has modified the processing method and stated that preparing fish powder can be by
drying fish either whole or muscle without employing solvent extraction. Production of fish powder using drying
technique of oven, spray and freeze drying at 50-60°C can extend the storage life minimum of one year at 10°C
without loss of sensory attributes (Huda et al., 2000). Venugopal et al. (1996) reported that drying methods, types
of additives and processing conditions are some of the factors which can affect the functionality, stability and
sensory properties of fish powder. Production fish powder from lean fish have longer storage shelf at ambient
temperature compared to fatty fish as fat is the main factor to loss sensory attributes. Mohamed et al. (2014) stated
that fish powder has high levels of essential amino acids, such as lysine, methionine and cysteine compared to
cereal products. In addition to its high digestibility and biological values it is also a good source of vitamins and
minerals. Osibona (2011) has done a research on comparative study of proximate composition, amino and fatty
acids of some economically important fish species in Lagos, Nigeria and found that mineral content of fish powder
was 121.97 mg/100 g calcium, 109.31 mg/100 g potassium, 110.05 mg/100 g zinc and 115.23 mg/100 g sodium.
Vanugopal (2005) highlighted that fish and fish products are very rich in nutritive value due to the essential amino
acid favorable patter. Compared with protein from plant source, fish protein is rich in all essential amino acids,
particularly lysine and methionine, which lack enough amounts of one or more essential amino acids.
Venugopal et al. (1996) reported that fish powder is an excellent dietary supplement and can be used to fortify
diverse range of cereal products to provide a healthy source of easily digested proteins. Enrichment of tilapia fish
protein in to bread from wheat flour was done by Adeleke and Odedeji (2010) resulted in an improvement of the
nutritional value of bread. It was found that protein content of bread (18.01) was more compared to the control
(9.08%). Based on the findings the researchers suggested that acceptable fortified biscuit and bread could be
produced from wheat and tilapia fish protein powder.
3.4 Nutritive value of fish powder and its application in food products
Proteins derived from fish are nutritionally superior when compared to those of plant sources. They have a better
balance of the dietary essential amino acids compared to all other animal protein sources (Friedman, 1996; Netto
et al., 2014).
