Effect of Cooking Method on the Proximate, Amino Acid and Fatty Acid Compositions of Clarias gariepinus and Oreochromis niloticus

Abstract

Abstract:The proximate, amino acid and fatty acid compositions of the fillet and oil of two commonly consumed fresh water fishes -Clarias gariepinus (Catfish) and Oreochromis niloticus (Tilapia) -were evaluated in this study. The samples were separately boiled, roasted (over hot charcoal) and fried using different types of oils (palm oil, groundnut oil, soybean oil and refined palm oil) and the effect of the processing methods on the nutritional composition was determined. The moisture content ranged from 76.27% for catfish to 79.97% for tilapia while the oil content ranged from 7.80% for tilapia and 11.00% for catfish. Ash content was in the range 8.03 -9.16% and the protein content was 15.83 -18.48%. The cooking methods resulted in a variation in the nutrient composition but no significant variation was observed in the amino acid composition except for the samples fried with palm oil which recorded significantly reduced essential amino acid contents. All the fish samples -both fresh and processed -have amino acid scores less than 100, with lysine, threonine and the sulfurcontaining amino acids being among the limiting amino acids. Both fish samples contain more unsaturated than saturated fatty acids.Keywords: Fish; proximate composition; fatty acid; amino acid.

Evaluation of fatty acid‐related nutritional quality indices in fried and raw nile tilapia, (Oreochromis Niloticus), fish muscles

“…This results are very similar to the other previous study findings conducted in other international and Ethiopia (Lema Abelti, 2017;Robert, Mfilinge, Limbu, & Mwita, 2014). Usually, these fatty acids are considered as the most saturated fatty acids (Oluwaniyi, Dosumu, & Awolola, 2017). As it is shown in the Table 5, the total saturated fatty acid from the raw Nile tilapia fish muscle was found to be 47.4%.…”

“…However, this value was found to be higher than the study done in Nigeria (36.56%) (Oluwaniyi et al, 2017). The difference with the earlier study might be due to the natural ecosystem mainly affecting the fish nutrition.…”

“…The total saturated fatty acids of fried Nile tilapia in the current study were found to be 51.8% of the total fatty acids which were higher compared with other study done in Nigeria (42.4%) (Oluwaniyi et al, 2017). In both studies, the type of oil used was palm oil.…”

“…Linoleic (C18.2 n-6), EPA (C20.5 n-3), and DHA (C22.6 n-3) present in the raw fish samples. The total unsaturated fatty acid of fried fish muscle was 47.21% which was less the study done in Nigeria (57.4%) (Oluwaniyi et al, 2017). The reason for the difference again probably goes to the cycles and time of frying.…”

“…In addition to the frying oil, method of preparation has also effect on fatty acid composition. The changes could be on both saturated an unsaturated fatty acids (Oluwaniyi et al, 2017). Others studies prove still these occurrences.…”