Methodology
How the Freshness Index works
Olive oil is a fresh product — peer-reviewed storage studies consistently show meaningful polyphenol decline within the first year after harvest, and the famous UC Davis Olive Center shelf studies showed how little a supermarket label guarantees. Yet most bottles carry only a “best by” date, typically set from bottling — which can itself be a year or more after harvest. We grade the thing labels hide. We do not score taste, and no one can pay for a grade.
Our stance: unknown = stale until proven fresh. If a bottle won’t tell you its age, we score that silence.
The rubric — 100 points, three components
I. Disclosure — 40 points
What the label itself tells a shopper.
| Harvest date printed on the bottle | 40 |
| Inconsistent / unconfirmed (“mixed”) | 25 |
| Bottling date only | 15 |
| Best-by date only | 0 |
II. Shelf recency — 40 points
Months from printed harvest date to a verified, photographed sighting of the bottle on a real shelf. Scored from the most recent staff-verified sighting; oils with no sighting yet score zero and carry a provisional badge.
| Under 6 months | 40 |
| 6–12 months | 30 |
| 12–18 months | 15 |
| Over 18 months | 5 |
| Undeterminable from the bottle | 0 |
III. Verification — 20 points
Whether the producer publishes proof a shopper could check.
| Lot-level lab results with a test date (acidity, peroxide, polyphenols) | 20 |
| Generic certification or undated claims | 10 |
| Nothing published | 0 |
Grade bands
| A+ | 95–100 | Full transparency and verifiably fresh shelf stock |
| A | 85–94 | Harvest-dated, fresh, well-documented |
| A− | 80–84 | Strong transparency, minor gaps |
| B | 65–79 | Meaningful disclosure, aging stock or thin proof |
| C | 50–64 | Partial transparency — or good practice awaiting a sighting |
| D | 35–49 | Little to go on |
| F | 0–34 | The label tells you nothing about freshness |
Evidence standards
- Grades are computed, not written. Every grade derives mechanically from the rubric; the component breakdown is shown on every oil page.
- Sightings are the atomic unit. A sighting is a specific bottle, in a specific store, on a specific date, with a photographed date stamp. Only staff-verified sightings affect grades. Community sightings are checked before they count.
- Desk research is labeled. Entries graded from producer websites and label imagery — before a physical sighting — are marked provisional, and their research notes say so.
- We buy retail. Audit bottles are purchased anonymously at retail, receipts kept. We do not accept samples for grading.
- Freshness is not a purity or safety claim. A grade measures transparency and age, not whether an oil meets extra-virgin chemical standards — we don’t allege fraud, we grade what brands prove.
Corrections & regrades
Think a grade is wrong? Brands: send current lot data, label photography, or lab reports to hello@primapressa.com and we regrade on evidence — usually within a week, with the change logged on the oil’s page. Shoppers: a photographed date stamp from a real shelf is the single most useful thing you can send us.
Conflicts
Primapressa also curates a seasonal harvest drop. The index and the drop are separated: drop oils are graded by the same public rubric as everyone else, rankings are computed from the data with no manual placement, and nothing on this site is paid for by any brand.