Rinsing food and Refreezing

[ScubaSteve]

Unless the packaging says zero nitrates/phosphates or it is very high quality there will be a sizable amount there. Largely it depends on the source...

If the seafood is farmed (a surprising amount of shrimp, prawn and oyster prepackaged in the stores are) N/P will be high because they don't do water changes until about 2-3 weeks before harvesting. Water changes are costly but N/P cause crappy flavours (if you've ever had cheap prawns that taste "muddy" this is why), so they change the water just before harvesting to try and pull N/P our of the animals systems. We won't taste it but the N/P levels are still high.

If they are fresh caught and frozen, the seafood still can become laden with N/P due to the equimpent and process water in the packaging facility. A lot of dead sea critters will leave behind quite a bit of mess which then starts to break down. Again, we won't taste it but it's there.

The only way you can ensure that your sea food is mostly N/P free is to go to a fishmonger and buy the sea food fresh caught and hasn't been through processing. You can then wash it, smoosh it and freeze it yourself.

I'm not talkin' out of my a** here. I've been learning this stuff over the past year as I am developing denitrator technologies for fish farming and water treatment tech for drinking water. Since learning this I only buy fresh now and since then my nitrates and phosphates dropped off the charts (well until a recent filter incident that is...).