the effect of modified atmosphere packaging (map) on the physicochemical properties of saffron flower at the storage time

saffron is the most important iranian non oil export. improper conditions of saffron flower storage increases microbial contamination and decreases saffron quality. this study was done for prolonging the shelf life of saffron flower in modified atmosphere packaging and subsequent to producing a new method for exporting the fresh saffron flower as cut flower. saffron flowers were packed in a polymer (polyamide- polyethylene bags) and three gas combinations of co2, o2, and n2 (30%,5%,65%; 50%,5%,45% and 70%,5%,25% respectively). samples and control (without packaging) were kept at 0˚c for 15 days. every three days the concentrations of oxygen and carbon dioxide inside the packages, the yield of product, physical (weight loss, percent of the flowers welter, the length and diameter of fresh stigma) and chemical properties (percent of moisture and the amount of crocin, safranal and picrocrocin of dried stigma) were measured. the existence of e.coli and enumeration of yeasts and moulds also were done. the results showed that modified atmosphere packaging increased the shelf life of saffron flowers. the chemical and physical qualities of control were lost strongly during 9 days. there were no evident for e.coli growth in the samples. enumeration of yeasts and moulds showed that most treatments were seen the national standard of iran (103cfu/gr).