Saffron is grown in arid and semi-arid regions in Iran in late autumn, winter and late spring with rainy season. It should be irrigated by supplemental basin irrigation. Since rainfall is usually delayed in autumn, therefore, a pre-flowering irrigation of about 100 mm is needed. In areas with a seasonal rainfall of 600 mm a post- flowering irrigation of about 50 mm is adequate for economical yield. In areas with seasonal rainfall of 400 and 200 mm continuous supplemental irrigation is needed with intervals of 24 and 15 days or irrigation regimes of 50% ETp and 75% ETp, respectively. In these areas, irrigation regimes can be planned based on crop water stress index (CWSI) of 0.60 and 0.27, respectively. Monthly values of crop coefficient (Kc) and pan coefficient (Kp) for saffron arepresented with the highest values of 1.10 and 0.84, respectively, that occurred in January. For the three-, four-and five-year old fields with higher amount of corm intensity the optimum irrigation water is zero for about 300 mm of rainfall. While for the six-and seven-year old fields the optimum irrigation water is zero for about 500 mm of rainfall. Flower production decreased 49% by using irrigation water with salinity level of 1.7 dS m-1 and no flower produced at salinity level of 4.0 dS m-1, while leaf growth occurred in this salinity. Furthermore, 50% flower yield is produced at soil water salinity of 3.6 dS m-1.

A flavonol, kaempferol, isolated from the fresh flower petals of C. sativus L. (Iridaceae) as the sole component. The structure of the compound was determined by chemical and spectroscopic methods.

Nanoemulsions are a colloidal dispersion of oil/water or water/oil phases stabilized by emulsifiers. The physicochemical properties of nanoemulsions have made them suitable candidates for the delivery of bioactive compounds. Oil-in-water nanoemulsions are proper carriers for hydrophobic and water-in-oil or water-in-oil-in-water nanoemulsions are good carriers for hydrophilic compounds. Saffron is an expensive bulbous stemless herb whose different bioactive ingredients including crocins, crocetin, safranal, picrocrocin, and essential oils have valuable nutritional, medicinal, pharmaceutical, and antimicrobial properties. The use of nanoemulsion technology is a promising approach for saffron processing. The emulsion liquid membrane is one of the effective techniques for extracting saffron bioactive. On the other hand, encapsulating saffron extract in nanoemulsion droplets can increase the stability, bioavailability, and controlled release of bioactive ingredients of saffron. Due to its inherent antimicrobial activity, saffron can be used in the form of nanoemulsion coatings to increase the quality and shelf life of food products. In this study, the existing studies on saffron nanoemulsions processing were reviewed. The application of nanoemulsion techniques for saffron extraction, saffron bioactive nanoencapsulation, as well as the probable preservative properties of saffron essential oils for food packaging have been discussed. This article also reveals information on two recent patents on the subject of saffron nanoemulsion by ultrasonic method.

The present investigation reports a quantitative analysis of metals in the saffron samples collected from seven different saffron production areas in the Khorasan Razavi province, Iran. Khorasan Razavi is the leading producer of saffron in Iran, and more than 95% of the global production of this expensive spice is attributed to Iran. Since environmental pollution is increasing, saffron is contaminated with various organic and inorganic contaminants such as heavy metals. Twenty-one saffron samples were collected in the flowering season of 2018 and analyzed for metal content. The concentration of microelements and heavy metals including Zn, Fe, Ca, Mn, Mg, Na, K, Pb, Cd, Cu, and Cr was determined in the samples collected from three farms in each production area with graphite furnace and flame atomic absorption spectroscopy. The results revealed that the collected saffron stigmas contain a wide range of minerals and heavy metals with different concentrations. Potassium is the most abundant element, and Cd had the least concentration in the saffron. It can be concluded that ecological management plans such as reducing chemical fertilizers and improving organic fertilizers can decline the extent of heavy metals in the saffron.