Effect of Drying Processes on Stability of Anthocyanin Extracts from Saffron Petal

Abstract

ABSTRACT. Saffron (Crocus sativus) has cyanic color flowers with major colorant of anthocyanin. Attractive color and functional properties of anthocyanins make them a good substitute for synthetic pigments in the food industry. These natural soluble water colorants are rather unstable and influenced by final processing treatment. The drying process is critical to the stability of saffron petals anthocyanins. Four different dehydration methods were evaluated: traditional method (at room temperature and under the sun); dehydration with electrical oven at different temperatures; and dehydration with microwave at different powers. The results showed that the highest amount of anthocyanin was obtained when saffron petals treated by traditional methods (at room temperature and under the sun). According to the results, the stability of saffron petals anthocyanins gradually accessed with increase of the heating temperature and decrement of heating time until 100 °C. However, heated at 120 and 140 °C, the anthocyanins could break down, and their residual amounts declined within 20 min and 10 min, respectively. The results suggested that saffron petals anthocyanins tended to degrade at high temperatures (>100 °C). Between these methods, drying at room temperature and drying with microwave at 900 W obtained the highest and the lowest results respectively.

Studying the thin-layer drying kinetics and qualitative characteristics of dehydrated saffron petals

“…But, high share of producing saffron is exclusively dedicated to producing and drying saffron stigmas whereas their violet color petals are mostly ignored and get disposed of. In the meanwhile, saffron petal is one of the most economical sources of anthocyanin pigments (Hemmati Khakhki, 2001;Heydari et al, 2014 ;Nørbaek, Brandt, Nielsen, Ørgaard, & Jacobsen, 2002;Williams, Harborne, & Goldblatt, 1986). Attractive color and functional properties such as antimicrobial properties, antiemetic, antipyretic, anti-itch, anti-inflammatory, hypertensive, antiarrhythmic (irregular heartbeats), sedative, analgesic, and antioxidant properties of anthocyanins can make them a good substitute for synthetic pigments in the food industry (Castañeda-Ovando, de Lourdes Pacheco-Hern andez, P aez-Hern andez, Rodríguez, & Gal an-Vidal, 2009;Kafi, 2006;Khosrokhavar, Ahmadiani, & Shamsa, 2010).…”

Refractance‐window as an innovative approach for the drying of saffron petals and stigma

“…As Table shows, increasing temperature (even 10 °C) decreased drying time substantially; so, 80 °C resulted in the shortest drying time. Heydrai, Rezaei, and Haghayegh (), studying the effect of different drying processes on stability of anthocyanin extracts from saffron petal, reported that microwave drying shortened process duration from 40 min for oven drying (80 °C) to 16 min at microwave powder of 180 W and 6 min at microwave power of 900 W. However, it has been demonstrated now that microwave drying, especially at high powers, could bring about irreversible color and physicochemical changes in the final product (Orsat, Changrue, & Raghavan, ).…”

Valorization of Moroccan Crocus sativus L. By-products: Foliar Spraying of Aqueous Tepal Extract Stimulates Growth and Confers Antioxidant Properties in Eggplant Seedling under Greenhouse Conditions

“…Irrigation management of saffron consists of six applications: in the middle of summer, the second in early October, the third in November, the fourth in late December, the fifth in early March, and the sixth in early April. After 180 days from the sowing date (October), tepals were separated by hand shortly after collecting in the field and were dried, in the dark, for 8–10 days, by the traditional methods at room temperature to avoid the degradation of the main bioactive molecules [ 21 ]. After drying, the tepals were crushed and stored at -20°C until use—the same harvesting and drying method was repeated in the same site's 2019 harvest plots.…”