Freshness is something you preserve.

Many marine fish naturally contain trimethylamine N-oxide, usually shortened to TMAO. After the fish dies, certain spoilage bacteria can convert it into trimethylamine, or TMA: a compound associated with that familiar fishy odor. Species, temperature, and handling all influence how spoilage develops. (FAO, n.d.)

That helps explain a useful piece of shopping advice: the FDA says fish should have a mild, fresh smell. Strong fishy, sour, rancid, or ammonia-like odors are reasons to pass it by. (FDA, n.d.)

Different species have different natural aromas. The point is that a powerful off-odor is something to take seriously, rather than something to disguise with lemon.

A mild smell is a quality clue, not proof of safety. Safe handling and temperature control still matter.

Odor tells another story, too. Fish fats can react with oxygen in a process called lipid oxidation. In oily fish, that process contributes to rancid aromas and flavors, and it can continue during frozen storage. (FAO, n.d.)

EPA and DHA, the long-chain omega-3 fatty acids found in seafood and marine oils, are particularly susceptible to oxidation. Their chemistry makes protection from oxygen, light, and heat an important part of maintaining oil quality. As oxidation progresses, it creates primary products such as lipid peroxides and a changing mixture of secondary breakdown products. (Albert et al., 2013)

These are different processes. Smelling a fillet cannot tell you its EPA and DHA content or give you a complete measurement of its oxidative condition. (FAO, n.d.)

How researchers measure oxidation.

Oil testing commonly looks at more than one stage of the process:

PVPeroxide value

Measures primary oxidation products. A 2015 survey of fish oils used a voluntary limit of 5 mEq/kg.

AVAnisidine value

Assesses certain secondary oxidation products. The same survey used a limit of 20.

TOTOXTotal oxidation value

Combines the two: TOTOX = 2 × PV + AV. The same survey used a limit of 26.

Peroxides can break down as oxidation advances, so a low PV alone can be misleading. These voluntary benchmarks assess oil quality; they are not established thresholds for harm in people. (Jackowski et al., 2015) (Albert et al., 2013)

A review of oxidized marine oils highlighted gaps in the human evidence. Laboratory and animal findings do not, by themselves, demonstrate that oxidation levels measured in retail supplements cause human illness. (Albert et al., 2013)

We can make the case for thoughtful preservation without overstating the health evidence. Flavor, quality, and transparency are already worth protecting.

“Never frozen” tells you one thing about a fish’s history. It doesn’t tell you how quickly it was chilled, how long it traveled, or how consistently it stayed cold.

NOAA notes that frozen seafood can be an excellent choice because a catch may be processed and frozen promptly. A well-managed frozen supply chain offers a way to preserve quality early, rather than relying on a short refrigerated selling window. (NOAA Fisheries, 2023)

Freezing technique matters. Ice formation affects muscle structure, which is one reason researchers study how freezing and thawing methods influence fish texture. Methods that produce finer, more uniform crystals can reduce structural damage. (Alizadeh, 2012)

But freezing cannot restore quality already lost. It also doesn’t stop every change: fats can still oxidize during frozen storage. Temperature, time, and packaging remain part of the story. (FAO, n.d.)

That’s why our seafood is blast-frozen to -10°F at harvest and vacuum sealed: the aim is to protect the quality the farm starts with.

Preservation is one chapter in a much longer story.

Harvest and handling affect the quality a producer has available to preserve. Prompt dispatch, careful handling, and rapid chilling are practical measures that help protect fish quality. Rough treatment can bruise flesh; delays in chilling create opportunities for deterioration. (NC State Extension, n.d.)

At Seatopia, we look at the whole journey: how seafood is raised, what it is fed, how it is harvested, and how it is handled afterward.

Well-run aquaculture offers an opportunity to plan that journey. Producers can coordinate harvests, processing, and preservation, and document the steps along the way. That’s an opportunity we value, and a reason to ask detailed questions of every farm.

Excellent handling also exists in wild fisheries, and farming alone guarantees nothing. The practices are what count.

A whole-food way to enjoy omega-3s.

For people who enjoy fish, whole seafood brings something a capsule cannot: a meal.

Alongside marine omega-3s, you’re enjoying protein, flavor, and naturally occurring nutrients whose amounts vary by species and sample. You’re also building a habit around food you look forward to eating.

Supplements can have a useful place, including for people who don’t eat seafood or have specific nutritional needs. Oil quality is a reason to choose carefully, not a reason to dismiss an entire category.

Our focus is the seafood on your plate: thoughtfully raised, carefully handled, and preserved with attention to temperature, oxygen, and time.