Is trout safe to eat? (wild and farmed trout)
In this article, we will discuss whether it is safe to eat trout, the possible risks of eating trout, if farmed trout is safer to eat than wild trout, and how to handle trout to improve its safety consumption.
Commercialised trout originates both from wild catches and farmed fish. Although some differences regarding the nutritional properties between farmed and wild trout are noticed, both fish are considered nutritious, but both can bring risks.
Is trout safe to eat?
Yes, trout is safe to eat. Rainbow trout are widely consumed due to its rapid growth and improved nutritional properties (1). Trout can originate from game fishing and farmed fish.
Trout, like other fish species, is an important source of proteins and omega-3 polyunsaturated fatty acids (1). Concerns about eating trout are also similar to other fish species, being the risk of heavy metals and chemical contamination (1, 2).
In addition, trout is a very perishable food product and can be a health risk due to microbial contamination, when not properly handled (4).
What are the risks of eating trout?
The risks of eating farmed or wild trout are summarised in the table below (1, 2, 4, 5):
|Consumption of trout that is contaminated by pathogenic microorganisms||Foodborne infection with symptoms such as diarrhoea, stomach cramps, vomiting, nausea and flu-like symptoms|
|Consumption of trout that is contaminated by a high concentration of histamine, or Scombroid toxin||Food poisoning by the Scombrotoxin with symptoms such as nausea, vomiting, skin rashes and heart palpitations. Scobrotoxin or histamine is produced by microbial degradation of proteins in fish|
|Ingestion of heavy metals||Fish from wildlife or farming is often contaminated by mercury or other heavy metals||The accumulative ingestion of heavy metals can cause neurological disorders and impaired development, especially in children|
|Ingestion of chemical contaminants||Chemical contaminants derived from chemical pollutants can be found in fish in large quantities||The effect of frequent ingestion of chemical pollutants such as polychlorinated biphenyls can lead to negative effects on health|
Is farmed trout safer to eat than wild trout?
No, farmed trout is not safer to eat than wild trout. According to studies, both farmed trout and wild trout presented a high concentration of Lead and above the considered safe for consumption in more than half samples analysed (1).
On the other hand, the levels of Mercury were considered safe, as well as the levels of Arsenic in all samples analysed of both wild and farmed trout.
Is rainbow trout safer to eat than steelhead trout?
No, rainbow trout is not safer to eat than steelhead trout. They are not different fish species but are considered the same species called Oncorhynchus mykiss (6), which may follow different habitats and living conditions during development.
O. mykiss is an anadromous fish, which can develop in saltwater or freshwater and then migrate to freshwater to spawn. Most of the trout for human consumption is farmed, however, both farmed and escaped trout can contain heavy metals (1, 7).
In a study, the levels of heavy metals in wild and farmed trout were considered safe and below the levels for tolerable daily intake (7). In another study, trout of both origins contained high levels of Cadmium in many samples analysed (1).
Is farmed trout more nutritious than wild trout?
No, farmed trout is not more nutritious than wild trout. In general wild trout is generally richer in omega-3 polyunsaturated fatty acids than farmed fish. In addition, wild trout is richer in proteins than farmed trout and is lower in moisture (3).
Feeding and environmental conditions affect the growth and the body composition and explain the differences between farmed and wild trout, although wild trout contains less total unsaturated fats, it contains more EPA omega-3.
EPA, or eicosapentaenoic acid is one of the most important essential fatty acids for human health for cardiovascular disease prevention and brain development (1, 3, 4).
How to safely consume trout?
To safely consume trout, it is important to purchase fresh fish and keep the trout refrigerated at all times (4, 5). Contamination occurs mostly due to poor handling and improper storage of fish. Follow the safety tips:
- Avoid fish with signs of spoilage, such as discolouration, opaque gills, off-odours, loss of texture and slime
- Consume fresh fish within 2 days and maintain fish refrigerated at home and during transportation
- To increase the shelf life of fish, cook the fish and consume it in 4 days or freeze the fish and consume it in 3 months
- Follow improved hygienic conditions and avoid cross-contamination between cooked and uncooked food items
- Cook fish to a minimum temperature of 145 °F (63 °C)
- Due to the risk of heavy metals in a high concentration, consume trout in moderation, especially if you are a pregnant woman or an elderly individual
In this article, we discussed the safety of eating trout, both wild or farmed, as well as the risks of eating trout and how to consume trout safely.
Trout is a very flavorful fish that is commercialised year-round in many parts of the world, due to its improved nutritional properties. Freshly caught and cooked trout is one of my favourite fish dishes.
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