Lot Certificates: Check the Freshness of Your Bottle

What peroxide value is, and why it is the number to ask for

Almost everything on an omega-3 label is a quantity: milligrams of EPA, milligrams of DHA, milligrams of krill oil. None of it tells you the thing that decides whether a capsule works or repeats on you all afternoon, which is how much the oil had already gone rancid before you swallowed it. That has a measurement. It is called peroxide value, it is reported in milliequivalents per kilogram (mEq/kg), and it is tested lot by lot. Lower is fresher.

Milligrams of EPA and DHA tell you what went into the capsule when the oil was pressed. Peroxide value tells you what is in it now — the part you actually swallow, and the part responsible for the fishy repeat that makes people quit omega-3 supplements altogether.

So here is the useful thing to do with this page: ask any omega-3 brand for their peroxide value and the limit it was measured against. Most cannot produce either number. A few will send a certificate with the freshness line missing. That comparison is the entire reason this page exists.

Why the number comes out this low

Krill oxidizes fast — it begins breaking down within minutes of coming out of the water, which is why most krill oil is frozen, shipped, thawed and processed onshore weeks later. Ours is cold-pressed on the boat, without solvents, in small lots, by a small family operation. That costs more to do and we have not found a way to make it cheaper. The peroxide number above is what you are paying the difference for. If you want the full arithmetic, including the parts that do not flatter us: Why Is Krill Oil So Expensive? The Honest Breakdown.

Try it against your current bottle

Cut one of your current softgels open and smell it, then do the same with one of ours. Fresh krill oil smells briny and clean, like the ocean. Oxidized oil smells sharp, fishy, or faintly like old paint. You do not need a laboratory to tell the difference, and once you have smelled both you will not go back to guessing. The 2-pack on Amazon ships with Prime.

Why we publish the numbers but not the laboratory’s name

Laboratories and contract manufacturers charge a separate licensing fee to have their name and certifications used in marketing, and being named shifts liability onto them. We do not pay that fee, so we do not use the name. What we publish instead is the part that is worth something to you: the measured values, the specification limits and the test methods. A name proves nothing. A number measured against a stated limit by a stated method is checkable.

If your lot is not listed yet

Reply to your order confirmation email with the lot number from your bottle and we will publish that lot's results here. New certificates are added as each shipment arrives.