Confusion with other spices

Black cumin seeds

Caraway fruits are similar in shape and structure to cumin seeds

Cumin is sometimes confused with caraway (Carum carvi), another spice in the parsley family (Apiaceae). Many European and Asian languages do not distinguish clearly between the two; for example, in Indonesia both are called jinten. Many Slavic and Uralic languages refer to cumin as "Roman caraway" or "spice caraway". The distantly related Bunium persicum and Bunium bulbocastanum and the unrelated Nigella sativa are both sometimes called black cumin (q.v.).^[14]

Cultivation areas

India is the world's largest producer of cumin, accounting for about 70%. The other major cumin-producing countries are Syria (13%), Turkey (5%), UAE (3%), and Iran.^[21] India produced 856,000 tons of cumin seed in the 2020–2021 fiscal year.^[22]

Climatic requirements

Cumin is a drought-tolerant tropical or subtropical crop. It is vulnerable to frost and has a growth season of 120 frost-free days.^[23] The optimum growth temperature ranges are between 25 and 30 °C (77 and 86 °F).^[12] The Mediterranean climate is most suitable for its growth. Cultivation of cumin requires a long, hot summer of three to four months. At low temperatures, the leaf color changes from green to purple. High temperatures might reduce growth period and induce early ripening. In India, cumin is sown from October until the beginning of December, and harvesting starts in February.^[12] In Syria and Iran, cumin is sown from mid-November until mid-December (extensions up to mid-January are possible) and harvested in June/July.^[12]

Grading

The three noteworthy sorts of cumin seeds in the market vary in seed shading, amount of oil, and flavor.^[24]

• Iranian
• Indian, South Asian
• Middle Eastern

Cultivation parameters

Cumin is grown from seeds. The seeds need 2 to 5 °C (36 to 41 °F) for emergence, an optimum of 20–30 °C (68–86 °F) is suggested. Cumin is vulnerable to frost damage, especially at flowering and early seed formation stages.^[12] Methods to reduce frost damage are spraying with sulfuric acid (0.1%), irrigating the crop prior to frost incidence, setting up windbreaks, or creating an early-morning smoke cover.^[12] The seedlings of cumin are rather small and their vigor is low. Soaking the seeds for 8 hours before sowing enhances germination.^[12] For an optimal plant population, a sowing density of 12–15 kilograms per hectare (11–13 lb/acre) is recommended.^[12] Fertile, sandy, loamy soils with good aeration, proper drainage, and high oxygen availability are preferred. The pH optimum of the soil ranges from 6.8 to 8.3.^[12] Cumin seedlings are sensitive to salinity^[25] and emergence from heavy soils is rather difficult. Therefore, a proper seedbed preparation (smooth bed) is crucial for the optimal establishment of cumin.

Two sowing methods are used for cumin, broadcasting and line sowing.^[12] For broadcast sowing, the field is divided into beds and the seeds are uniformly broadcast in this bed. Afterwards, they are covered with soil using a rake. For line sowing, shallow furrows are prepared with hooks at a distance of 20 to 25 cm (8 to 10 in). The seeds are then placed in these furrows and covered with soil. Line sowing offers advantages for intercultural operations such as weeding, hoeing, or spraying.^[12] The recommended sowing depth is 1–2 cm and the recommended sowing density is around 120 plants per m². The water requirements of cumin are lower than those of many other species.^[12] Despite this, cumin is often irrigated after sowing to be sure that enough moisture is available for seedling development. The amount and frequency of irrigation depends on the climate conditions.^[12]

Cultivation management

The relative humidity in the center of origin of cumin is rather low. High relative humidity (i.e. wet years) favors fungal diseases. Cumin is especially sensitive to Alternaria blight and Fusarium wilt. Early-sown crops exhibit stronger disease effects than late-sown crops. The most important disease is Fusarium wilt, resulting in yield losses up to 80%.^[12] Fusarium is seed- or soil-borne and it requires distinct soil temperatures for the development of epidemics.^[12] Inadequate fertilization might favor Fusarium epidemics.^[12] Cumin blight (Alternaria) appears in the form of dark brown spots on leaves and stems.^[12] When the weather is cloudy after flowering, the incidence of the disease is increased.^[12] Another, but less important, disease is powdery mildew. Incidence of powdery mildew in early development can cause drastic yield losses because no seeds are formed.^[12] Later in development, powdery mildew causes discolored, small seeds.^[12]

Pathogens can lead to high reductions in crop yield. Cumin can be attacked by aphids (Myzus persicae) at the flowering stage. They suck the sap of the plant from tender parts and flowers. The plant becomes yellow, the seed formation is reduced (yield reduction), and the quality of the harvested product decreases. Heavily infested plant parts should be removed. Other important pests are the mites (Petrobia latens) which frequently attack the crop. Since the mites mostly feed on young leaves, the infestation is more severe on young inflorescences.^[26]

The open canopy of cumin is another problem. Only a low proportion of the incoming light is absorbed. The leaf area index of cumin is low (about 1.5). This might be a problem because weeds can compete with cumin for essential resources such as water and light and thereby lower yield. The slow growth and the short stature of cumin favors weed competition additionally.^[12] Two hoeing and weeding sessions (30 and 60 days after sowing) are needed for the control of weeds. During the first weeding session (30 days after sowing), thinning should be done, as well, to remove excess plants. The use of preplant or pre-emergence herbicides is very effective in India,^[12] but this kind of herbicide application requires soil moisture for a successful weed control.^[27]

Breeding

Cumin is a diploid species with 14 chromosomes (i.e. 2n = 14). The chromosomes of the different varieties have morphological similarities with no distinct variation in length and volume. Most of the varieties available today are selections.^[12] The variabilities of yield and yield components are high. Varieties are developed by sib mating in enclosed chambers^[12] or by biotechnology. Cumin is a cross-pollinator, i.e. the breeds are already hybrids. Therefore, methods used for breeding are in vitro regenerations, DNA technologies, and gene transfers. The in vitro cultivation of cumin allows the production of genetically identical plants. The main sources for the explants used in vitro regenerations are embryos, hypocotyl, shoot internodes, leaves, and cotyledons. One goal of cumin breeding is to improve its resistance to biotic (fungal diseases) and abiotic (cold, drought, salinity) stresses. The potential genetic variability for conventional breeding of cumin is limited and research about cumin genetics is scarce.^[29]

Traditional

In India, the seeds are powdered and used in different forms such as kashaya (decoction), arishta (fermented decoction), and vati (tablet/pills), and processed with ghee (a semifluid clarified butter). In traditional medicine practices of several countries, dried cumin seeds are believed to have medicinal purposes,^[9] although there is no scientific evidence for any use as a drug or medicine.^[9]

Volatiles and essential oil

Cuminaldehyde, cymene, and terpenoids are the major volatile components of cumin oil, which is used for a variety of flavors, perfumes, and essential oil.^[14][31] Cumin oil may be used as an ingredient in some cosmetics.^[32]

Aroma

Cumin's flavor and warm aroma are due to its essential oil content, primarily the aroma compound cuminaldehyde.^[31] Other aroma compounds of toasted cumin are the substituted pyrazines, 2-ethoxy-3-isopropylpyrazine, 2-methoxy-3-sec-butylpyrazine, and 2-methoxy-3-methylpyrazine. Other components include γ-terpinene, safranal, p-cymene, and β-pinene.^[33][34][35]

Nutritional value

In a reference amount of 100 grams (3.5 oz), cumin seeds provide high amounts of the Daily Value for fat (especially monounsaturated fat), protein, and dietary fiber (table). B vitamins, vitamin E, and several dietary minerals, especially iron, magnesium, and manganese, are present in substantial Daily Value amounts (table).