QUALITATIVE DIAGNOSTIC OF CROCUS SATIVUS L. FROM DIFFERENT ENDEMIC ORIGINS OF TALIOUINE REGION IN THE SOUTH OF MOROCCO: HYGROSCOPIC BEHAVIOR AND MAIN SECONDARY METABOLITES ANALYSIS

This study examined the water activity and equilibrium moisture content of saffron stigmas from different aeras of Taliouine region, south of Morocco with a diversity of altitudes and climates. The static gravimetric method was used to explain the hygroscopic behavior of saffron at three different temperatures (30, 40, and 50 °C). The quality of these saffron samples was evaluated by determining the concentration of their main compounds: safranal, crocin and picrocrocin using the ISO 3632-2 method by UV-vis. The water activity for conservation of Crocus sativus L. was range between 0.32 and 0.34 under the experimental conditions. The impact of the three irrigation systems (drip, gravity and porous) on the water activity has been studied. All the six endemic origins identified by altitudes (2100 m, 1700 m, 1600 m, 1500 m, 1200 m and 1000 m) used in this diagnosis were classified according to ISO 3632-1 in two classes: categories I for saffron from altitudes 1700, 1600 and 1200 m and categories II for saffron from altitudes 2100, 1500 and 1000 m. The samples from altitude 1700 m recorded high quality of secondary metabolites represented by concentrations of crocin (291.68  ) and picrocrocin (120.11  ).