Saffron: Origin, Grades, Adulteration and Uses of the Most Expensive Spice

Saffron is the dried stigma of a crocus flower, three threads to a bloom, and Encyclopaedia Britannica still calls it the most expensive spice in the world.¹ A pinch does three jobs at once: it colors food a deep yellow-gold, adds a bitter edge and brings a hay-like, honeyed aroma that’s hard to fake. Each of those lines up with one compound, and those compounds are exactly what the international quality standard measures.

At a glance

Measured values

12 figures, sourced

Measure	Value	Scope	Source
Coloring strength (crocin), minimum Limit	230 ISO 3632 value: absorbance of a 1% water extract at about 440 nm	ISO 3632-1:2025, as reported by Agilent's application note, Extra Class	agilent.com
Bitterness (picrocrocin), minimum Limit	80 ISO 3632 value: absorbance of a 1% water extract at about 257 nm	ISO 3632-1:2025, as reported by Agilent's application note, Extra Class	agilent.com
Aroma (safranal), range Limit	30–50 ISO 3632 value: absorbance of a 1% water extract at about 330 nm	ISO 3632-1:2025, as reported by Agilent's application note, Extra Class	agilent.com
Coloring strength (crocin), minimum Limit	200 ISO 3632 value: absorbance of a 1% water extract at about 440 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade IA 2022 paper written before the 2025 edition describes three categories (I, II, III) with the same minimums for those grades (s6).	agilent.com
Bitterness (picrocrocin), minimum Limit	70 ISO 3632 value: absorbance of a 1% water extract at about 257 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade I	agilent.com
Aroma (safranal), range Limit	20–50 ISO 3632 value: absorbance of a 1% water extract at about 330 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade I	agilent.com
Coloring strength (crocin), minimum Limit	170 ISO 3632 value: absorbance of a 1% water extract at about 440 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade IIA 2022 paper written before the 2025 edition describes three categories (I, II, III) with the same minimums for those grades (s6).	agilent.com
Bitterness (picrocrocin), minimum Limit	55 ISO 3632 value: absorbance of a 1% water extract at about 257 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade II	agilent.com
Aroma (safranal), range Limit	20–50 ISO 3632 value: absorbance of a 1% water extract at about 330 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade II	agilent.com
Coloring strength (crocin), minimum Limit	120 ISO 3632 value: absorbance of a 1% water extract at about 440 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade IIIA 2022 paper written before the 2025 edition describes three categories (I, II, III) with the same minimums for those grades (s6).	agilent.com
Bitterness (picrocrocin), minimum Limit	40 ISO 3632 value: absorbance of a 1% water extract at about 257 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade III	agilent.com
Aroma (safranal), range Limit	20–50 ISO 3632 value: absorbance of a 1% water extract at about 330 nm	ISO 3632-1:2025, as reported by Agilent's application note, Grade III	agilent.com

Each figure is quoted as its source states it, with the samples or standard it applies to. Where sources differ, both are shown; nothing is averaged. All measured values

Flavor, aroma and the compounds behind them

Saffron has a strong aroma and a bitter taste. You’ll also see it called honeyed, hay-like, floral or faintly metallic. Those are descriptions, not measurements, and the balance shifts with the dish and with how much you use.

The chemistry is better pinned down. Crocin is the coloring matter.¹ Picrocrocin is the main bittering agent, and safranal is the main contributor to aroma.⁵ The color is water-soluble (Britannica notes a water-soluble fabric dye made from the stigmas in India). That’s why you steep saffron in warm liquid before it goes into a dish. (Crocetin sometimes gets credit for the color, but our sources name crocin.)

Origin and history

The plant. Saffron crocus is triploid, which disrupts seed formation and leaves it at least partly sterile. It’s propagated almost entirely from daughter corms, so every saffron field is in effect a planting of clones. A 2022 review of the genetic and artistic evidence concludes that it most likely emerged and was domesticated in ancient Greece, with Crocus cartwrightianus generally assumed to be at least one parent.⁸

Bronze Age. The best-known early images are Aegean frescoes. The 2022 review dates the Minoan-influenced pictures of cultivated saffron to 1700–1500 BCE, including wall paintings from the Xeste 3 and West House buildings at Akrotiri on Thera (Santorini).⁸ An AHPA history dates the Thera frescoes to about 1650 BCE.³

Rome and the Arab world. Knowledge of crocus passed from classical Greece to Rome and, through translated Greek medical texts, into the Arabic world. Britannica records that Rome’s streets were strewn with saffron when Nero entered the city.¹

Spain. Britannica says the Arabs were growing saffron in Spain around 961, and that it may then have vanished from western Europe until the Crusaders brought it back.¹

The word. English saffron goes back to around 1200, through Old French safran and Medieval Latin safranum, and ultimately to Arabic az-za’faran, a word whose own origin is unknown.

Fraud and punishment. Faking saffron has been a crime for a long time. Court records from mid-14th-century Montpellier describe inspectors seizing impure saffron from a pepperer’s shop and the town ordering it publicly burned.⁹ A Metropolitan Museum of Art essay, citing a secondary herbal reference, says a 15th-century Nuremberg trader was buried alive with his adulterated product.¹⁰ The claim, repeated all over the internet, that German adulterators were “burned at the stake” didn’t turn up in any of our sources.

Medieval European growing areas. Valencia, Nuremberg and Saffron Walden in England were among places once known for growing it. Closer to home, University of Vermont Extension notes that saffron has been grown in parts of Pennsylvania for more than 200 years, mostly for household use.¹¹

Production: who grows it, and how many flowers it takes

Iran’s share. Every source we checked puts Iran first, but the tonnages differ:

The 160-ton and 430-ton figures can’t both describe the same harvest, and neither source explains its method. The “around 90%” share matches across two 2022 peer-reviewed papers, but neither ties it to a specific crop year. We found no FAO or other official statistical series for saffron, so treat any single tonnage as approximate.

AHPA lists the next producers as India (22 tons), Greece (7.2), Afghanistan (6), Morocco (2.6), Spain (2.3), and Italy and China at about 1 ton each, without dates for those figures.³ By those numbers Italy is a small producer, not a major one.

Flowers per unit of saffron. It’s the most repeated saffron statistic and the least consistent:

We haven’t reconciled these, and you shouldn’t average them. Converted to a common unit, they range from roughly 22,000 to 300,000 flowers per kilogram, and none of the sources explain the spread. You’ll also see a figure of 225,000 stigmas per pound. That’s Britannica’s 75,000 flowers times three stigmas each, so it’s one defensible reading of one source, not a settled number.

Price. Bergomi et al. describe saffron as the highest-priced high-value agricultural product, reaching up to 20,000 EUR/kg.⁴ That’s a ceiling quoted in a 2022 paper, not a market average, and we found no dated retail price series. For why it costs so much, see why saffron is so expensive.

Buying and quality

ISO 3632: how saffron is graded

The international standard comes in two parts. ISO 3632-1, now in its third edition (July 2025), sets the requirements for dried saffron sold as filaments, cut filaments and powder, with storage and transport recommendations in an annex.⁶ ISO 3632-2:2010 sets out the test methods.⁷

Grading rests on UV-visible spectrophotometry of a 1% water extract. Absorbance at about 440 nm tracks crocin (coloring strength), about 257 nm tracks picrocrocin (bitterness), and about 330 nm tracks safranal (aroma). Under the 2025 edition, as reported by Agilent’s application note on the method, there are four grades:⁵

A 2022 paper, written before the 2025 edition came out, describes the standard as having three categories (I, II, III) with the same minimums for those three grades.⁴ When a seller quotes a “coloring strength” number, that’s the 440 nm value. Higher means more crocin.

Where the test falls short. The ISO absorbance method can’t tell synthetic color from natural pigment, so a dyed product can score well on the color test.⁴ Labs that want to confirm authenticity add other methods on top.

Adulteration

Saffron is one of the most adulterated spices, and powdered saffron is the easiest to cheat with.⁴ A 2022 bulletin from the ABC-AHP-NCNPR Botanical Adulterants Prevention Program, as reported by NutraIngredients, lists materials found sold as or mixed into saffron:¹²

• Safflower (Carthamus tinctorius) and calendula flowers
• Corn stigmas (corn silk) dyed in beet juice
• Pomegranate peel or fibers
• Red-dyed paper strips and silk fibers
• Ground turmeric and paprika (in powders)
• Other naturally red plant material, and in at least one reported case plastic “stigmas”

Older adulterants in the literature include synthetic and organic dyes, other parts of the crocus plant, and weight-adding coatings like syrup, honey or glycerin.⁴ Safflower has gone by “false saffron” for a long time. See safflower and safflower vs. saffron for how the two differ.

What you can reasonably do. The research singles out powder as the form most at risk, so threads are the safer buy.⁴ A lab certificate stating ISO 3632 grade and coloring strength tells you more than a label that just says “premium.” But the color test can be fooled by dyes, so it’s evidence of strength, not proof of purity. Home tricks like watching how fast threads bleed color in water get passed around a lot. None of our sources validate them as a purity test.

How saffron is used

Britannica notes saffron’s use to color and flavor many Mediterranean and Asian dishes, especially rice and fish; in English, Scandinavian and Balkan breads; and as an important ingredient in bouillabaisse.¹ In Spain it’s part of paella, which Britannica defines as saffron-flavored rice cooked with meat, seafood and vegetables, from the rice-growing Mediterranean coast around Valencia. Swedish saffron buns fall under Britannica’s Scandinavian breads. Saffron is also closely tied to Milanese risotto, Persian rice and Indian sweets, but we didn’t find a qualifying source for each, so we’re not presenting them as checked facts.

Technique matters more than quantity. The color is water-soluble, so steep crumbled threads in a little warm water, stock or milk before adding the liquid to the dish. Saffron is potent, and a pinch is a typical starting point. More on technique at cooking with saffron, with dish ideas at saffron uses and paella spices. If a dish has gone medicinal or bitter, see too much saffron.

Storage

ISO 3632-1:2025 includes storage and transport recommendations in an annex, but we couldn’t get the text.⁶ We found no sourced shelf-life figure, and the ones floating around online can’t be traced. Keep it dry, dark, cool and sealed. Practical tips at how to store saffron.

Health research and safety

Saffron has mostly been studied as a supplement, which isn’t the same as eating it in food. Nothing here means saffron treats or prevents any disease.

• Depression and anxiety. A 2019 systematic review and meta-analysis in Nutrition Reviews pooled randomized trials and found a large effect of saffron over placebo on depressive symptoms. The authors flag real limits: 21 of the 23 studies were done in Iran, and statistical testing found evidence of publication bias.¹³
• Memory and dementia. A 2020 meta-analysis found four randomized trials in mild cognitive impairment and Alzheimer’s disease that reported better scores on a cognition scale than placebo, but concluded there isn’t enough evidence for any clinical recommendation.¹⁴
• Eye health. A 2019 narrative (not systematic) review found six clinical studies of vision measures in age-related macular degeneration and called the data promising but too limited for firm, evidence-based recommendations.¹⁵
• Cancer and pain relief. You’ll see claims that saffron fights cancer or relieves pain. We found no human evidence for either.

Safety. A 2017 toxicology review concluded that therapeutic doses of saffron showed no significant toxicity in clinical or experimental studies.¹⁶ The Drugs.com monograph says saffron in culinary amounts isn’t generally associated with toxicity. It says amounts above 5 g, far more than food uses, have uterine stimulant and abortive effects, and it records one case of anaphylaxis. The same monograph gives 10 g as an abortive dose and 20 g as a lethal dose. It draws on a 2004 compendium and doesn’t show where those figures were measured, so treat them as cautions, not precise thresholds.¹⁷ If you’re pregnant, don’t take saffron supplements without medical advice.

Don’t confuse saffron with meadow saffron. Meadow saffron or autumn crocus (Colchicum autumnale) is a different, poisonous plant.¹⁰ Historical reports of saffron being “lethal” may come from mixing up the two.³

Substitutes and comparisons

Nothing reproduces saffron’s aroma. Turmeric, safflower and annatto can supply the color, each with its own flavor. See:

• Saffron substitutes
• Saffron vs. turmeric and turmeric
• Safflower vs. saffron
• Achiote powder (annatto)
• Saffron vs. sassafras

Footnotes

1. “Saffron,” Encyclopaedia Britannica. britannica.com · Reference work ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

2. Crocus sativus L., Plants of the World Online, Royal Botanic Gardens, Kew. powo.science.kew.org · Reference work ↩

3. Touwaide and Appetiti, “Herbs in History: Saffron,” American Herbal Products Association, 2022. ahpa.org · Publication ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

4. Bergomi et al., “Determination of Saffron Quality through a Multi-Analytical Approach,” Foods, 2022. pmc.ncbi.nlm.nih.gov · Peer-reviewed ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

5. “Quality Assessment of Saffron by UV-Vis Spectroscopy in Accordance with ISO 3632,” Agilent Technologies application note, 2025. agilent.com · Publication ↩ ↩² ↩³

6. ISO 3632-1:2025, Spices — Saffron — Part 1: Specification, ISO. iso.org · Standard ↩ ↩² ↩³

7. ISO 3632-2:2010, Spices — Saffron — Part 2: Test methods, ISO. iso.org · Standard ↩ ↩²

8. Kazemi-Shahandashti et al., “Ancient Artworks and Crocus Genetics Both Support Saffron’s Origin in Early Greece,” Frontiers in Plant Science, 2022. frontiersin.org · Peer-reviewed ↩ ↩² ↩³

9. Reyerson, “Commercial fraud in the middle ages: the case of the dissembling pepperer,” Journal of Medieval History, 1982. experts.umn.edu · Peer-reviewed ↩

10. Still, “Dyeing for Color,” The Metropolitan Museum of Art, 2015. metmuseum.org · Publication ↩ ↩²

11. Benoit, “Saffron: the world’s most expensive spice,” University of Vermont Extension, 2024. uvm.edu · Reference work ↩ ↩²

12. Daniells, “Adulterants Bulletin highlights ‘multifaceted fraud’ associated with saffron,” NutraIngredients, 2022. nutraingredients.com · Publication ↩

13. Marx et al., “Effect of saffron supplementation on symptoms of depression and anxiety,” Nutrition Reviews, 2019. pure.bond.edu.au · Peer-reviewed ↩

14. Ayati et al., “Saffron for mild cognitive impairment and dementia,” BMC Complementary Medicine and Therapies, 2020. doaj.org · Peer-reviewed ↩

15. Heitmar et al., “Saffron (Crocus sativus L.) in Ocular Diseases,” Nutrients, 2019. mdpi.com · Peer-reviewed ↩

16. Bostan et al., “Toxicology effects of saffron and its constituents: a review,” Iranian Journal of Basic Medical Sciences, 2017. journals.mums.ac.ir · Peer-reviewed ↩

17. “Saffron,” Drugs.com professional monograph. drugs.com · Reference work ↩

Also drawn on

• saffron (n.), Online Etymology Dictionary. etymonline.com
• Paella, Encyclopaedia Britannica. britannica.com