The impact of ozone on health-promoting, microbiological, and colour properties of Rubus ideaus raspberries

The purpose of the study was to define the impact of ozonisation duration and concentration on selected chemical, physical, and microbiological properties of Rubus ideaus red-fruited raspberries of the Polka variety. Raspberry fruit was exposed to a stream of ozone in concentration of 0.3 and 0.9mg/L over a period of 60 and 120min. The scope of the study covered the measurements of titratable acidity, soluble solids concentration, and such health-promoting indicators as content of phenol compounds, flavonoids, anthocyanins and vitamins C, total antioxidant activity (TAA) on 0, 4th, and 8th day of storage. The ozone treated fruit had higher level of phenol compounds and demonstrated higher TAA compared to untreated raspberries. The use of ozone made it possible to curb the development of yeast and moulds on the surface of raspberries, in which the dosage of 0.9mg/L and treatment time of 60min proved most efficient.