How long does raw tuna steak last in the fridge? (How to increase tuna shelf life)

In this brief guide, we are going to answer the question “How long does raw tuna steak last in the fridge” with an in-depth analysis of the shelf life of tuna steak in different conditions. Moreover, we are going to discuss the different ways to tell if your raw tuna steak has gone bad and the health implications that eating a bad tuna steak can pose.

How long does raw tuna steak last in the fridge?

The longevity of raw tuna steak is relatively brief. When properly stored in a refrigerator at or below 40°F (4.4°C) in an airtight container, fresh, chilled, and unpacked tuna typically maintains its quality for a span of 2 to 3 days. Conversely, vacuum-packed tuna exhibits a longer shelf life, lasting approximately 5 to 7 days under similar storage conditions.

The decline in freshness and quality of fresh fish during storage can be attributed to various factors, including microbiological spoilage, autolytic degradation, and lipid oxidation. (1, 2)

What factors affect the shelf life of raw tuna steak?

Tuna is a highly perishable seafood item prone to both chemical and microbiological deterioration. The elevated water activity, a high postmortem pH (>6), and an abundance of low molecular weight components create an optimal environment for bacterial proliferation.

This bacterial growth is primarily accountable for sensory degradation. The primary factors behind tuna’s decline in quality during refrigerated storage are lipid and myoglobin oxidation, which play a significant role in reducing the shelf life of perishable foods.

Lipid oxidation can occur through non-enzymatic or enzymatic processes, often resulting in the development of rancidity. Simultaneously, myoglobin oxidation leads to a transformation in meat color, shifting it from red to brown as metmyoglobin forms.

Additionally, freshly caught fish undergo natural microbial spoilage, where various components break down, giving rise to new compounds. These compounds are responsible for alterations in the color, flavor, odor, and texture of the fish flesh.

The loss of vibrant color and the emergence of strong odors are particularly detrimental qualities that render tuna products unappealing to consumers. (3, 4)

Can raw tuna steak be frozen?

Yes. Freezing, as a low-temperature preservation method, stands out as a means to extend the shelf life of fish and fish products over more extended periods, though it may have some impact on certain quality aspects. Typically, freezing is carried out at temperatures ranging from −18 to −40 °C, varying depending on the type of fish in storage.

Unlike chilling, frozen storage effectively prevents the proliferation of most deteriorative and pathogenic microorganisms at temperatures below −10 °C. At this low temperature, approximately 80% of the water content in the fish transforms into ice, thereby reducing water activity and inhibiting microbial activity.

The shelf life of frozen tuna typically ranges from 4 to 12 months, contingent on several factors including the initial quality of the fish and the storage conditions. Quality preservation, on the other hand, is primarily influenced by the stability of the storage temperature and the avoidance of temperature fluctuations. (2)

What are the signs of tuna steak spoilage?

There are several signs of tuna spoilage. Lipid oxidation can manifest through enzymatic or non-enzymatic processes, resulting in the development of off-flavors. Conversely, hemoglobin oxidation contributes to a shift in meat color, from a purplish-red hue (deoxymyoglobin) to brown (metmyoglobin).

Lipid and hemoglobin oxidation are the primary drivers of tuna alteration during its shelf life. Microbial growth represents the foremost mechanism responsible for tuna deterioration and stands as the key factor affecting the quality of fresh or lightly preserved tuna.

Initially, the muscle tissues of fish are sterile, but after death, they become susceptible to contamination by the microbial population present on the fish’s skin. This contamination leads to undesirable transformations in appearance, texture, flavor, and odor, ultimately compromising the overall quality of the fish.

The spoilage caused by microorganisms results in the production of volatile amines, biogenic amines, organic acids, sulfides, alcohols, aldehydes, and ketones, all of which contribute to the development of unpleasant and unacceptable off-flavors. (2, 5)

How to increase raw tuna shelf life?

Numerous strategies have been explored to enhance the shelf life of fresh fish while minimizing any adverse effects on its quality, particularly its texture. The objective is to extend its shelf life beyond that achievable through refrigeration alone, to avoid the necessity for freezing preservation.

These strategies involve the introduction of additional measures before traditional storage methods are employed. These measures include the application of edible films and coatings, as well as the adoption of nonthermal preservation techniques like hyperbaric storage.

These approaches serve to slow down microbial growth, akin to refrigeration, while also potentially reducing microbial populations to more favorable levels and mitigating degradation reactions, ultimately prolonging the shelf life of fresh tuna.

In terms of packing several innovative techniques have emerged with the overarching goal of preserving the quality and extending the shelf life of tuna products. One approach involves the extension of the shelf life of fresh chilled tuna through vacuum packaging or modified atmosphere packaging.

Additionally, active packaging methods have gained prominence, where active agents are integrated and released within the packaged tuna products.

This form of packaging proves highly effective in controlling microorganism growth and preventing enzymatic deterioration and lipid oxidation. Notably, there has been a growing interest in the utilization of natural active agents in recent years. (1-3)

What happens if you eat bad tuna steak?

Fish products, like tuna, have the potential to act as carriers for various foodborne pathogenic microorganisms, with contamination stemming from both environmental factors and processing procedures.

Additionally, inadequate storage conditions, particularly temperature mismanagement, can facilitate pathogen growth, increasing the risk of reaching infective levels. Histamine fish poisoning (HFP) represents the leading cause of foodborne infections associated with fish consumption.

HFP occurs when individuals ingest a concentrated amount of histamine produced as a result of bacterial decarboxylation of free histidine. Scombroid fish, such as tuna, are often implicated due to their high levels of free histidine in muscle tissues.

Common symptoms of HFP include skin rashes, diarrhea, facial reddening or flushing (sometimes extending to the neck, arms, and upper body), sweating, headaches, and vomiting.

Furthermore, consumption of fresh contaminated tuna can lead to Salmonella infections, characterized by symptoms such as diarrhea, fever, and abdominal cramps typically manifesting within 72 hours of exposure. The duration of this infection typically spans four to seven days, with most individuals recovering without the need for medical intervention. (4, 6)

Other FAQs about Tuna which you may be interested in.

How long does a tuna sandwich last in the fridge?

Conclusion

In this brief guide, we answered the question “How long does tuna steak last in the fridge” with an in-depth analysis of the shelf life of tuna steak in different conditions. Moreover, we discussed the different ways to tell if your raw tuna steak has gone bad and the health implications that eating a bad tuna steak can pose.

References