Chemical and Microbiological Characterization of Egyptian Cultivars for Some Spices and Herbs Commonly Exported Abroad

Abstract

The present study highlighted some chemical, nutritional, microbiological and essential oil characteristics of the Egyptian traditional cultivars for seeds of cumin ( Cum inum cyminum ) and coriander ( Coriandum sativum ) spices as well as for basil whole herb ( Ocimum basilicum ) collected from different Egyptian export centers as being ready for export. The found values for humidity in dry seeds of cumin (7.4%) and coriander (6.4%) as well as total ash and ash insoluble in acid (in cumin 7.7% and 0.74%, but in coriander 5.3% and 0.55%, respectively) were lower than the maximum limits indicated by the Egyptian Specification Standards (ES) and by International Standards Organization (ISO) for cumin and coriander seeds. Analysis of essential minerals in seed spices and herbs indicated that they were are rich in K, Ca, Na, Fe and Zn. Total bacterial count was low content in seeds of cumin and coriander as well as fresh whole basil herb. The microbiological load in all tested seed spices and herbs was found lower than those indicated by the ES and ISO for cumin and coriander seeds. Yields in hydro-distilled essential oils (EOs) were the highest in cumin seeds (3.762%), while both coriander and basil herb had lower amounts (0.285% and 0.686%, respectively). EOs contents were found higher than the maximum limits for cumin (1.5% - 2.5% on dry weight basis), but the within the limits for coriander (0.1% - 0.5% on dry weight basis) as indicated by the ES and ISO for cumin and coriander seed oils. Gas chromatography of extracted EOs from seeds of cumin and coriander as well as basil herbs indicated the presence of 41, 35 and 47 compounds, respectively, where cuminaldehyde was the major component in cumin volatiles, but was linalool in volatiles of both coriander seeds and basil herbs. EOs of basil herbs grown in Egypt, were of the high linalool-chemotype which were characterized by high contents of linalool and relatively lower amounts of eugenol. However, the major compounds in the three tested EOs from seeds or herbs grown in Egypt are in accordance with literature reports from different parts of the world. Volatile oil components in EOs of the three tested Egyptian spices and herbs were classified into groups, based on the relative area (%). The proportion of the major and the other main components in EOs from seeds of cumin and coriander cultivars were within the ranges indicated by both the ES and ISO for cumin seed oils (cuminaldehyde between 15% - 46%) and for coriander seed oils (linalool between 65% - 78%). No Egyptian Specification Standards are established yet for fresh basil herbs and for basil oil of Linalool chemotype, but only present for basil oil of methylchavicol-chemotype.