# A Review on Food Safety: The Case of _Citrobacter_ sp., Fish and Fish Products
## 5 Isolation and Detection of Enterobacteria in Food Case: _Citrobacter_ sp.
In addition, it must be considered that histamine levels can vary enormously between the different parts of the fish body, so different samples of the same specimen or lot must always be selected and sent for analysis, in the case of diagnosis of poisonings [65]. Control and Prevention: Animal Health and Food Diseases by Consumption of Fish (Microbiology Contamination and Biogenic Amines)  
The presence of various microorganisms, including enterobacteria, such as _Citrobacter_, sp., in food production systems (aquaculture and fishing) is considered hazardous to animal health and a potential risk of contamination in the different phases of the food chain that can compromise food safety. For the control and prevention of diseases in animals, related to aquaculture activities and due to various causative agents, including bacteria, it is recommended to implement good hygiene practices, including personal hygiene, cleaning and filling of ponds, the management of the quantity and quality of water (microbiological conditions, temperature, dissolved oxygen concentration, pH, turbidity), appropriate fish population density in ponds, removal and daily elimination of sick or dead fish, avoiding the use of chemical substances, favoring a nutritious diet adequate in quantity and quality for armed fish, and the cleanliness of capture equipment and containers [88, 89]. Meanwhile, in the post-capture or harvest stages, the implementation of different procedures, practices, and/or food-safety-management systems, such as good manufacturing practices, Sanitation Standard Operating Procedures (SSOPs), and the Hazard Analysis Critical Control Points (HACCP) System, are a fundamental part of reducing the presence of pathogens and achieving the safety of fish and fish products intended for human consumption [89, 90, 91, 92, 93]. The histamine-producing microbial population is related to the natural microbiota of fish and the aquatic environment, as well as bacterial contamination of fish from poor hygienic practices and conditions during capture, handling, processing, and storage (including failures in the cold chain) that favor the acceleration of postmortem changes and the early appearance of signs of decomposition due to autolytic and microbial activity with sensory changes, composition, and pH, as well as the formation of biogenic amines (histamine, tyrosine, putrescine, and cadaverine, among others) that can affect the health of consumers [14, 23, 23, 53, 56, 59, 94]. For the control and prevention of the risk of histamine poisoning derived from fish consumption and considering that once the poison is generated, there is no treatment that inaccuracies it, it is necessary to apply actions to minimize the presence and activity of histamine-producing bacteria [67]. The presence and activity of biogenic amine-generating microorganisms in fish can be reduced by applying good manufacturing hygiene practices, effective cleaning, and disinfection procedures in processing areas, control of preservation, and storage temperatures with the use of low temperatures (0 \({}^{\circ}\)C or close) from the catch and throughout the food chain, as well as through the application of the HACCP system and control and prevention measures in the formation of biogenic amines in fish at dangerous levels [23, 26, 32, 56, 62, 67]. It is estimated that the optimum temperature for fish conservation, to avoid the generation of histamine, is close to 0 \({}^{\circ}\)C and no higher than 4 \({}^{\circ}\)C from the moment of capture, maintaining a constant temperature during all stages of the food chain [68, 79, 95, 96]. The production of histamine begins at temperatures of around 7 \({}^{\circ}\)C, with increased production from 20 \({}^{\circ}\)C. As such, the inadequate storage of fish, generally above 20 \({}^{\circ}\)C, seems to be the most important predisposing factor for the generation of high histamine levels [26, 96].