Comparative Analysis of Nutritional Value ofOreochromis niloticus(Linnaeus), Nile Tilapia, Meat from Three Different Ecosystems

Abstract

Determination of protein, lipid, and mineral content of fish meat is necessary to ensure that it meets requirements for food regulations and commercial specifications. The objective of the present study was to determine the chemical composition ofOreochromis niloticus(L.), Nile tilapia, under three different ecosystems: (1) high pollution and high density ofEichhornia crassipes, that is, water hyacinth (Lake Chivero), (2) medium pollution and medium density of water hyacinth (Lake Manyame), and (3) low pollution and low density of water hyacinth (Lake Kariba). Dry matter, protein, lipids, and ash were evaluated by proximate analysis. Minerals were determined by atomic absorption spectrophotometry and pH was determined by a pH meter. Lake Kariba fish had the highest percentage of dry matter, protein, and ash. These qualities were correlated to low levels of pollutants and high oxygen content in the harvest waters. The phosphorus content of fish from Lake Chivero was very high, in tandem with phosphate levels in the harvest waters. In addition, water from Lake Chivero had an alkaline pH, high nitrate, and low oxygen content. The results suggest that effluent from sewage works and fertilizer industries caused pollution and proliferation of water hyacinth, contributing to pervasion of the chemical composition of fish.

A Comparative Evaluation of Carcass Quality, Nutritional Value, and Consumer Preference of Oreochromis niloticus from Two Impoundments with Different Pollution Levels in Zimbabwe

“…The differences noted on ether extract and dry matter between fish from Lake Kariba and Lake Chivero are not surprising as nutritional value of most freshwater fish has been reported to differ between water bodies, fish size, and season [42]. Lake Chivero is highly polluted and so the feed resources and stress factors for fish in this lake are different when compared to Lake Kariba.…”

“…Fish in the length class 10-20 cm from Lake Chivero had the highest fat content and the least was from Lake Kariba in the same month. Normal fat content for Oreochromis niloticus is 2.75±0.16% but however varies with the geographical region, diet, season, sexual maturity, and age [42]. Considering the fat content of all the fish samples, all the fish were found to be classified as lean.…”

“…Protein content for all the fish from the two lakes in the two seasons was within the range that is classified as high which is greater than 15% [42]. When taking into account only the nutritional requirements for human health, fish from both sources can be reliable sources of nutrients if included in the diet but the fish may not be safe due to possibility of toxins and other poisonous substances that might accumulate in fish which include heavy metals and toxins.…”

Explorando diferentes subproductos considerados como residuos por la industria pesquera en México//Exploring different by-products considered as residues by the fishery industry in México

“…Ellos relacionaron el aumento de pH con la formación de productos básicos de descomposición como amonio y trimetilamina, indicando crecimiento bacteriano, pérdida de calidad y posible deterioro; el valor de pH en las muestras de TL está en un rango donde el deterioro aún no se hace evidente y se puede corroborar con el contenido de BVT observado, el cual se encontró muy por debajo del límite establecido por la regulación mexicana. Los valores de humedad obtenidos son similares a los observados para el sitio AT; no obstante, los subproductos TL no fueron expuestos al medio ambiente, por lo que se puede deducir que el alto contenido de huesos provenientes de la cabeza, cola y esqueletos, además del contenido visceral, hacen que el contenido de humedad sea menor al del músculo (79 %) (Jim et al, 2017). Bringas-Alvarado et al (2018), reportaron contenido de humedad de 61 % en homogeneizado de subproductos de tilapia, valor muy similar al de TL.…”

ASSESSING THE POST-HARVEST CHEMICAL AND MICROBIAL CHANGES IN THE MEAT OF ROHU (Labeo rohita) KEPT UNDER DIFFERENT STORAGE CONDITIONS

“…Fishing makes a considerable contribution to the economy of many countries that have fishing as an established field. Small-scale fisheries of developing countries are very important because they provide a nutritious food, which is often cheaper than meat; therefore, accessible to a larger number of people (Jim et al, 2017). Fish is a major source of protein, fat, minerals, vitamin and valuable omega-3 fatty acids contributing to food and nutrition security (Mohan et al,2016).…”