Investigation of the effect of conventional and cold storage on qualitative and quantitative characteristics of Iranian onion cultivars

A split-split plot design was used to evaluate the effects of different storage conditions on qualitative & quantitative characteristics of Iranian onion cultivars. Storage conditions (10oC, 50-60%RH and 4oC, 65-75%RH), cultivars (Azarshahr-Red, Neishabor-Red, Kashan-White and Isfahan-White) and storage time (0, 1, 2, 3 months) were assigned to main plot, sub plot and sub sub plot, respectively. Different characteristics such as, water loss, dry matter, firmness, changes in colour, total soluble solids and pyruvic acid (pungency index) were evaluated monthly, during storage. Results were analyzed using SAS software. LSD test was used for multiple comparisons of the mean values.Results revealed that stored onion at different storage conditions had significant differences in firmness, colour indices, weight loss, sprouting, spoilage and pungency. At different storage time, onions showed significant differences in above characteristics. Kashan-White, Neishabor-Red and Isfahan-White demonstrated higher firmness. Onion stored in conventional storage showed higher weight loss, sprouting and spoilage as compared with the onions in cold storage.