TY - JOUR

T1 - Characterization and finding the origin of off-flavor compounds in Nile tilapia cultured in net cages in hydroelectric reservoirs, São Paulo State, Brazil

AU - Podduturi, Raju

AU - da Silva David, Gianmarco

AU - da Silva, Reinaldo J.

AU - Hyldig, Grethe

AU - Jørgensen, Niels O.G.

AU - Agerlin Petersen, Mikael

N1 - Funding Information: This research was funded by the São Paulo Research Foundation (FAPESP) in Brazil , grant number 2013/50504-5 and by the Ministry of Higher Education and Science, the Strategic Research Council, Denmark , grant 3050-00008B . Publisher Copyright: © 2023 The Author(s)

PY - 2023

Y1 - 2023

N2 - An increasing demand for fish products has led to an intensive aquaculture production in Brazil, and cultivation of fish constituted 860 × 103 tons in 2022, contributing to the 87% of total fish consumption. Nile tilapia constitutes almost half of the aquaculture production, and most tilapia farms use floating net cages. One of the major constraints of intensive fish production is production of off-flavors. Release of nutrients by the fish leads to deterioration of the water quality and stimulates growth of microorganisms, also including off-flavor producing species. The objective of this study was to determine levels of taste and odor compounds (geosmin, 2-MIB and a selection of volatile compounds) and their impact on the flavor quality of Nile tilapia produced in net cages in reservoirs in São Paulo State, Brazil. GC-MS analysis of fish and water from six different farms showed concentrations of geosmin in the water from 1 to 8 ng/L, while geosmin in fish flesh ranged from 40 to 750 ng/kg. The level of 2-MIB in water was 2 to 25 ng/L, and 0 to 800 ng/kg fish. The GC-MS analysis also revealed presence of more than 100 volatile organic compounds in the fish flesh, consisting of aldehydes, alcohols, benzene derivatives, hydrocarbons, ketones and few other compounds. Geosmin and 2-MIB related flavor notes were detected in all fish by a sensory panel, and a high correlation between the chemical and sensory analyses was found. The potential impact of the volatile organic compounds on the fish flavor is discussed. Analysis of the water quality in the reservoirs indicated that levels of geosmin and 2-MIB levels were highly influenced by the nutrient levels in the water.

AB - An increasing demand for fish products has led to an intensive aquaculture production in Brazil, and cultivation of fish constituted 860 × 103 tons in 2022, contributing to the 87% of total fish consumption. Nile tilapia constitutes almost half of the aquaculture production, and most tilapia farms use floating net cages. One of the major constraints of intensive fish production is production of off-flavors. Release of nutrients by the fish leads to deterioration of the water quality and stimulates growth of microorganisms, also including off-flavor producing species. The objective of this study was to determine levels of taste and odor compounds (geosmin, 2-MIB and a selection of volatile compounds) and their impact on the flavor quality of Nile tilapia produced in net cages in reservoirs in São Paulo State, Brazil. GC-MS analysis of fish and water from six different farms showed concentrations of geosmin in the water from 1 to 8 ng/L, while geosmin in fish flesh ranged from 40 to 750 ng/kg. The level of 2-MIB in water was 2 to 25 ng/L, and 0 to 800 ng/kg fish. The GC-MS analysis also revealed presence of more than 100 volatile organic compounds in the fish flesh, consisting of aldehydes, alcohols, benzene derivatives, hydrocarbons, ketones and few other compounds. Geosmin and 2-MIB related flavor notes were detected in all fish by a sensory panel, and a high correlation between the chemical and sensory analyses was found. The potential impact of the volatile organic compounds on the fish flavor is discussed. Analysis of the water quality in the reservoirs indicated that levels of geosmin and 2-MIB levels were highly influenced by the nutrient levels in the water.

KW - Fish flavor

KW - Geosmin and 2-MIB

KW - São Paulo reservoirs

KW - Tilapia in net cages

KW - Volatile compounds

U2 - 10.1016/j.foodres.2023.113375

DO - 10.1016/j.foodres.2023.113375

M3 - Journal article

C2 - 37803713

AN - SCOPUS:85168251881

VL - 173

JO - Food Research International

JF - Food Research International

SN - 0963-9969

M1 - 113375

ER -