EFFECT OF FILM PACKAGING ON PHYTOPATHOLOGICAL AND PHYSIOLOGICAL PROCESSES OF FRESH-CUT WHITE ASPARAGUS (ASPARAGUS OFFICINALIS L.) DURING STORAGE

The effect of polypropylene-film (PP-film) and P-Plus-film on changes in fungal growth, related changes in the carbohydrate pattern (fructose, glucose and sucrose) of film wrapped peeled asparagus and changes in the oxygen and carbon dioxide concentrations within the film packaging was measured at harvest and after 3 days of shelf life (20°C). At harvest, endophytic contamination with Idriella bolleyi (30%), Cladosporium macrocarpum (3.3%), Verticillium spp. (1.7%), Penicillium spp. (1.7%) and Fusarium oxysporum (1.7%) was found. After three days of storage, the development of fungi was inhibited, possibly as a result of the decline in the oxygen concentration in the P-Plus-film (8.2%) and in PP-film (0.18%). Idriella bolleyi decreased by 8.3% in PP-film packaging and by 16.7% in the P-Plus-film indicating a better adaptation to varying physiological conditions in postharvest. The different film packaging material accounted for the variability in oxygen concentration (98%), fungal growth (93%), glucose (93%) and fructose (81%). Correlations were found between fungal growth and sucrose concentration (r=0.65, P<0.05), oxygen concentration (r=0.62, P<0.05), carbon dioxide concentration (r=-0.62, P<0.05). The development of fungi was inhibited by the gaseous composition within the film-packaging unit and/or by the limited source of carbohydrates available. Furthermore, the non-pathogenic fungus Idriella bolleyi, a known antagonist, might have been inhibited by the growth of Cladosporium spp., Fusarium spp., Penicillium spp. and Verticillium spp.