Saffron

Saffron () is a spice derived from the flower of ''Crocus sativus'', commonly known as the "saffron crocus". The vivid crimson stigma and styles, called threads, are collected and dried for use mainly as a seasoning and colouring agent in food. Although some doubts remain on its origin, it is believed that saffron originated in Iran. However, Greece and Mesopotamia have also been suggested as the possible region of origin of this plant. Saffron crocus slowly propagated throughout much of Eurasia and was later brought to parts of North Africa, North America, and Oceania.

Saffron's taste and iodoform-like or hay-like fragrance result from the phytochemicals picrocrocin and safranal. It also contains a carotenoid pigment, crocin, which imparts a rich golden-yellow hue to dishes and textiles. Its recorded history is attested in a 7th-century BC Assyrian botanical treatise, and has been traded and used for thousands of years. In the 21st century, Iran produces some 90% of the world total for saffron. At US$5,000 per kg or higher, saffron has long been the world's costliest spice by weight.

Etymology

A degree of uncertainty surrounds the origin of the English word "saffron". It might stem from the 12th-century Old French term ''safran'', which comes from the Latin word , from the Arabic (زَعْفَرَان), ''za'farān'', which comes from the Persian word ''zarparan'' meaning "gold strung" (implying either the golden stamens of the flower or the golden color it creates when used as flavor).

Species

Description

The domesticated saffron crocus, ''Crocus sativus'', is an autumn-flowering perennial plant unknown in the wild. It probably descends from the eastern Mediterranean autumn-flowering ''Crocus cartwrightianus'' which is also known as "wild saffron" and originated in Crete or Central Asia. '' C. thomasii'' and '' C. pallasii'' are other possible sources. As a genetically monomorphic clone, it slowly propagated throughout much of Eurasia.

It is a sterile triploid form, which means that three homologous sets of chromosomes make up each specimen's genetic complement; ''C. sativus'' bears eight chromosomal bodies per set, making for 24 in total. Being sterile, the purple flowers of ''C. sativus'' fail to produce viable seeds; reproduction hinges on human assistance: clusters of corms, underground, bulb-like, starch-storing organs, must be dug up, divided, and replanted. A corm survives for one season, producing via vegetative division up to ten "cormlets" that can grow into new plants in the next season. The compact corms are small, brown globules that can measure as large as in diameter, have a flat base, and are shrouded in a dense mat of parallel fibres; this coat is referred to as the "corm tunic". Corms also bear vertical fibres, thin and net-like, that grow up to above the plant's neck.

The plant sprouts 5–11 white and non- photosynthetic leaves known as cataphylls. These membrane-like structures cover and protect 5 to 11 true leaves as they bud and develop on the crocus flower. The latter are thin, straight, and blade-like green foliage leaves, which are , in diameter, which either expand after the flowers have opened ("hysteranthous") or do so simultaneously with their blooming ("synanthous"). ''C. sativus'' cataphylls are suspected by some to manifest prior to blooming when the plant is irrigated relatively early in the growing season. Its floral axes, or flower-bearing structures, bear bracteoles, or specialised leaves, that sprout from the flower stems; the latter are known as pedicels. After aestivating in spring, the plant sends up its true leaves, each up to in length. Only in October, after most other flowering plants have released their seeds, do its brilliantly hued flowers develop; they range from a light pastel shade of lilac to a darker and more striated mauve. The flowers possess a sweet, honey-like fragrance. Upon flowering, the plants are in height and bear up to four flowers. A three-pronged style in length, emerges from each flower. Each prong terminates with a vivid crimson stigma, which are the distal end of a carpel.

Cultivation

The saffron crocus, unknown in the wild, probably descends from ''Crocus cartwrightianus''. It is a triploid that is "self-incompatible" and male sterile; it undergoes aberrant meiosis and is hence incapable of independent sexual reproduction—all propagation is by vegetative multiplication via manual "divide-and-set" of a starter clone or by interspecific hybridisation.

''Crocus sativus'' thrives in the Mediterranean maquis, an ecotype superficially resembling the North American chaparral, and similar climates where hot and dry summer breezes sweep semi-arid lands. It can nonetheless survive cold winters, tolerating frosts as low as and short periods of snow cover. Irrigation is required if grown outside of moist environments such as Kashmir, where annual rainfall averages ; saffron-growing regions in Greece ( annually) and Spain () are far drier than the main cultivating Iranian regions. What makes this possible is the timing of the local wet seasons; generous spring rains and drier summers are optimal. Rain immediately preceding flowering boosts saffron yields; rainy or cold weather during flowering promotes disease and reduces yields. Persistently damp and hot conditions harm the crops, and rabbits, rats, and birds cause damage by digging up corms. Nematodes, leaf rusts, and corm rot pose other threats. Yet ''Bacillus subtilis'' inoculation may provide some benefit to growers by speeding corm growth and increasing stigma biomass yield.

The plants fare poorly in shady conditions; they grow best in full sunlight. Fields that slope towards the sunlight are optimal (i.e., south-sloping in the Northern Hemisphere). Planting is mostly done in June in the Northern Hemisphere, where corms are lodged deep; its roots, stems, and leaves can develop between October and February. Planting depth and corm spacing, in concert with climate, are critical factors in determining yields. Mother corms planted deeper yield higher-quality saffron, though form fewer flower buds and daughter corms. Italian growers optimise thread yield by planting deep and in rows apart; depths of optimise flower and corm production. Greek, Moroccan, and Spanish growers employ distinct depths and spacings that suit their locales.

''C. sativus'' prefers friable, loose, low-density, well-watered, and well-drained clay-calcareous soils with high organic content. Traditional raised beds promote good drainage. Soil organic content was historically boosted via application of some of manure. Afterwards, and with no further manure application, corms were planted. After a period of dormancy through the summer, the corms send up their narrow leaves and begin to bud in early autumn. Only in mid-autumn do they flower. Harvests are by necessity a speedy affair: after blossoming at dawn, flowers quickly wilt as the day passes. All plants bloom within a window of one or two weeks. Stigmas are dried quickly upon extraction and (preferably) sealed in airtight containers.

Harvesting

The high retail value of saffron is maintained on world markets because of labour-intensive harvesting methods, which require some – equivalently, . Forty hours of labour are needed to pick 150,000 flowers.

One freshly picked crocus flower yields on average 30 mg of fresh saffron or 7 mg dried; roughly 150 flowers yield of dry saffron threads; to produce of dried saffron, of flowers are needed; the yield of dried spice from fresh saffron is only .

Spice

Phytochemistry and sensory properties

Saffron contains some 28 volatile and aroma-yielding compounds, dominated by ketones and aldehydes. Its main aroma-active compounds are safranal – the main compound responsible for saffron aroma – 4-ketoisophorone, and dihydrooxophorone. Saffron also contains nonvolatile phytochemicals, including the carotenoids zeaxanthin, lycopene, various α- and β- carotenes, as well as crocetin and its glycoside crocein, which are the most biologically active components. Because crocetin is smaller and more water-soluble than the other carotenoids, it is more rapidly absorbed.

The yellow-orange colour of saffron is primarily the result of α-crocin. This crocin is trans-crocetin di-(β-D- gentiobiosyl) ester; it bears the systematic (IUPAC) name 8,8-diapo-8,8-carotenoic acid. This means that the crocin underlying saffron's aroma is a digentiobiose ester of the carotenoid crocetin. Crocins themselves are a series of hydrophilic carotenoids that are either monoglycosyl or diglycosyl polyene esters of crocetin. Crocetin is a conjugated polyene dicarboxylic acid that is hydrophobic, and thus oil-soluble. When crocetin is esterified with two water-soluble gentiobioses, which are sugars, a product results that is itself water-soluble. The resultant α-crocin is a carotenoid pigment that may make up more than 10% of dry saffron's mass. The two esterified gentiobioses make α-crocin ideal for colouring water-based and non-fatty foods such as rice dishes.

The bitter glucoside picrocrocin is responsible for saffron's pungent flavour. Picrocrocin (chemical formula: ; systematic name: 4-(β-D-glucopyranosyloxy)-2,6,6-trimethylcyclohex-1-ene-1-carbaldehyde) is a union of an aldehyde sub-molecule known as safranal (systematic name: 2,6,6-trimethylcyclohexa-1,3-diene-1-carbaldehyde) and a carbohydrate. It has insecticidal and pesticidal properties, and may comprise up to 4% of dry saffron. Picrocrocin is a truncated version of the carotenoid zeaxanthin that is produced via oxidative cleavage, and is the glycoside of the terpene aldehyde safranal.

When saffron is dried after its harvest, the heat, combined with enzymatic action, splits picrocrocin to yield D–glucose and a free safranal molecule. Safranal, a volatile oil, gives saffron much of its distinctive aroma. Safranal is less bitter than picrocrocin and may comprise up to 70% of dry saffron's volatile fraction in some samples. A second molecule underlying saffron's aroma is 2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1-one, which produces a scent described as saffron, dried hay-like. Chemists find this is the most powerful contributor to saffron's fragrance, despite its presence in a lesser quantity than safranal. Dry saffron is highly sensitive to fluctuating pH levels, and rapidly breaks down chemically in the presence of light and oxidising agents. It must, therefore, be stored away in air-tight containers to minimise contact with atmospheric oxygen. Saffron is somewhat more resistant to heat.

Grades and ISO 3632 categories

Saffron is not all of the same quality and strength. Strength is related to several factors including the amount of style picked along with the red stigma. Age of the saffron is also a factor. More style included means the saffron is less strong gram for gram because the colour and flavour are concentrated in the red stigmas. Saffron from Iran, Spain and Kashmir is classified into various grades according to the relative amounts of red stigma and yellow styles it contains. Grades of Iranian saffron are: ''sargol'' (red stigma tips only, strongest grade), ''pushal'' or ''pushali'' (red stigmas plus some yellow style, lower strength), "bunch" saffron (red stigmas plus large amount of yellow style, presented in a tiny bundle like a miniature wheatsheaf) and ''konge'' (yellow style only, claimed to have aroma but with very little, if any, colouring potential). Grades of Spanish saffron are ''coupé'' (the strongest grade, like Iranian sargol), ''mancha'' (like Iranian pushal), and in order of further decreasing strength ''rio'', ''standard'' and ''sierra'' saffron. The word ''mancha'' in the Spanish classification can have two meanings: a general grade of saffron or a very high quality Spanish-grown saffron from a specific geographical origin. Real Spanish-grown La Mancha saffron has PDO protected status and this is displayed on the product packaging. Spanish growers fought hard for Protected Status because they felt that imports of Iranian saffron re-packaged in Spain and sold as "Spanish Mancha saffron" were undermining the genuine La Mancha brand. Similar was the case in Kashmir where imported Iranian saffron is mixed with local saffron and sold as "Kashmir brand" at a higher price. In Kashmir, saffron is mostly classified into two main categories called ''mongra'' (stigma alone) and ''lachha'' (stigmas attached with parts of the style). Countries producing less saffron do not have specialised words for different grades and may only produce one grade. Artisan producers in Europe and New Zealand have offset their higher labour charges for saffron harvesting by targeting quality, only offering extremely high-grade saffron.

In addition to descriptions based on how the saffron is picked, saffron may be categorised under the international standard ISO 3632 after laboratory measurement of crocin (responsible for saffron's colour), picrocrocin (taste), and safranal (fragrance or aroma) content. However, often there is no clear grading information on the product packaging and little of the saffron readily available in the UK is labelled with ISO category. This lack of information makes it hard for customers to make informed choices when comparing prices and buying saffron.

Under ISO 3632, determination of non-stigma content ("floral waste content") and other extraneous matter such as inorganic material ("ash") are also key. Grading standards are set by the International Organization for Standardization, a federation of national standards bodies. ISO 3632 deals exclusively with saffron and establishes three categories: III (poorest quality), II, and I (finest quality). Formerly there was also category IV, which was below category III. Samples are assigned categories by gauging the spice's crocin and picrocrocin content, revealed by measurements of specific spectrophotometric absorbance. Safranal is treated slightly differently and rather than there being threshold levels for each category, samples must give a reading of 20–50 for all categories.

These data are measured through spectrophotometry reports at certified testing laboratories worldwide. Higher absorbances imply greater levels of crocin, picrocrocin and safranal, and thus a greater colouring potential and therefore strength per gram. The absorbance reading of crocin is known as the "colouring strength" of that saffron. Saffron's colouring strength can range from lower than 80 (for all category IV saffron) up to 200 or greater (for category I). The world's finest samples (the selected, most red-maroon, tips of stigmas picked from the finest flowers) receive colouring strengths in excess of 250, making such saffron over three times more powerful than category IV saffron. Market prices for saffron types follow directly from these ISO categories. Sargol and coupé saffron would typically fall into ISO 3632 category I. Pushal and Mancha would probably be assigned to category II. On many saffron packaging labels, neither the ISO 3632 category nor the colouring strength (the measurement of crocin content) is displayed.

However, many growers, traders, and consumers reject such lab test numbers. Some people prefer a more holistic method of sampling batches of threads for taste, aroma, pliability, and other traits in a fashion similar to that practised by experienced wine tasters. However, ISO 3632 grade and colouring strength information allow consumers to make instant comparisons between the quality of different saffron brands, without needing to purchase and sample the saffron. In particular, consumers can work out a value for money based on price per unit of colouring strength rather than price per gram, given the wide possible range of colouring strengths that different kinds of saffron can have.

Adulteration

Despite attempts at quality control and standardisation, an extensive history of saffron adulteration, particularly among the cheapest grades, continues into modern times. Adulteration was first documented in Europe's Middle Ages, when those found selling adulterated saffron were executed under the ''Safranschou'' code. Typical methods include mixing in extraneous substances like beetroot, pomegranate fibres, red-dyed silk fibres, or the saffron crocus's tasteless and odourless yellow stamens. Other methods included dousing saffron fibres with viscid substances like honey or vegetable oil to increase their weight. Powdered saffron is more prone to adulteration, with turmeric, paprika, and other powders used as diluting fillers. Adulteration can also consist of selling mislabelled mixes of different saffron grades. Thus, high-grade Kashmiri saffron is often sold and mixed with cheaper Iranian imports; these mixes are then marketed as pure Kashmiri saffron, a development that has cost Kashmiri growers much of their income. Safflower is a common substitute sometimes sold as saffron. The spice is reportedly counterfeited with horse hair, corn silk, or shredded paper. Tartrazine or sunset yellow have been used to colour counterfeit powdered saffron.

In recent years, saffron adulterated with the colouring extract of gardenia fruits has been detected in the European market. This form of fraud is difficult to detect due to the presence of flavonoids and crocines in the gardenia-extracts similar to those naturally occurring in saffron. Detection methods have been developed by using HPLC and mass spectrometry to determine the presence of geniposide, a compound present in the fruits of gardenia, but not in saffron.

Types

The various saffron crocus cultivars give rise to thread types that are often regionally distributed and characteristically distinct. Varieties (not varieties in the botanical sense) from Spain, including the tradenames "Spanish Superior" and "Creme", are generally mellower in colour, flavour, and aroma; they are graded by government-imposed standards. Italian varieties are slightly more potent than Spanish. Greek saffron produced in the town of Krokos is PDO protected due to its particularly high-quality colour and strong flavour. Various "boutique" crops are available from New Zealand, France, Switzerland, England, the United States, and other countries—some of them organically grown. In the US, Pennsylvania Dutch saffron—known for its "earthy" notes—is marketed in small quantities.

Consumers may regard certain cultivars as "premium" quality. The "Aquila" saffron, or ''zafferano dell'Aquila'', is defined by high safranal and crocin content, distinctive thread shape, unusually pungent aroma, and intense colour; it is grown exclusively on eight hectares in the Navelli Valley of Italy's Abruzzo region, near L'Aquila. It was first introduced to Italy by a Dominican friar from inquisition-era Spain. But the biggest saffron cultivation in Italy is in San Gavino Monreale, Sardinia, where it is grown on 40 hectares, representing 60% of Italian production; it too has unusually high crocin, picrocrocin, and safranal content.

Another is the "Mongra" or "Lacha" saffron of Kashmir (''Crocus sativus'' 'Cashmirianus'), which is among the most difficult for consumers to obtain. Repeated droughts, blights, and crop failures in Kashmir combined with an Indian export ban, contribute to its prohibitive overseas prices. Kashmiri saffron is recognizable by its dark maroon-purple hue, making it among the world's darkest. In 2020, Kashmir Valley saffron was certified with a geographical indication from the Government of India.

Production

Almost all saffron grows in a belt from Spain in the west to Kashmir in the east. In 2014, were produced worldwide. Iran is responsible for 90–93% of global production, with much of their produce exported.

In the 21st century, cultivation in Greece and Afghanistan increased. Morocco and India were minor producers. In Italy, saffron is produced primarily in Southern Italy, especially in the Abruzzo region, but it is also grown in significant numbers in Basilicata, Sardegna, and Tuscany (especially in San Gimignano). Prohibitively high labour costs and abundant Iranian imports mean that only select locales continue the tedious harvest in Austria, Germany, and Switzerland—among them the Swiss village of Mund

HOME


Content is Copyleft
Website design, code, and AI is Copyrighted (c) 2014-2017 by Stephen Payne


Consider donating to Wikimedia



As an Amazon Associate I earn from qualifying purchases