Comparison of three storage techniques for post-harvest quality preservation of six commercially available cultivars of apple

To evaluate the influence of 1-methylcyclopropene (1-MCP) treatment and ultra-low oxygen storage systems (ULO 1 2.0 kPa CO2 and 1.0 kPa O-2) and (ULO 2 2.5 kPa CO2 and 1.5 kPa O-2) on the chemical composition, sensory quality and proliferation intensity of microorganisms during long-term storage of apple, a two-year study was conducted, using two autumn cultivars: 'Auksis', 'Orlik', and four winter cultivars: 'Antej', 'Belorusskoje Malinovoje', 'Sinap Orlovskij' and 'Zarja Alatau', grown in cool climate. Fruits were stored for 6 months and the alterations in weight, soluble solid content, titratable acidity, firmness and microorganism development on fruit surface were examined. To better understand consumers' attitude towards apple quality, the sensory analysis was performed. The results indicated that the most substantial positive effect on physical and chemical parameters and sensory quality has been achieved when ultra-low oxygen storage was applied. In general, all cultivars had retained better quality with regards to acids and soluble solids content. Likewise storage under ultra-low oxygen conditions, 1-Methylcyclopropene has positioned a strong positive effect on apple flesh firmness. Apples stored under different circumstances showed different contamination frequency and diversity of microorganisms, where the lowest incidence of microbial activity was found on apples stored under ultra-low oxygen, whereas the highest incidence of microbial activity was found on apples kept under storage in air.